Research Article
Saeid Mirzaei; Mehdi Rahimi; Ali Tajabadipour; Masoud Bahar; Bahram SharifNabi
Abstract
Introduction: The pistachio (Pistacia vera), a member of the cashew family, is a small tree originating from Central Asia and the Middle East. The tree produces seeds that are widely consumed as food. Pistacia vera often is confused with other species in the genus Pistacia that are also known as pistachio. ...
Read More
Introduction: The pistachio (Pistacia vera), a member of the cashew family, is a small tree originating from Central Asia and the Middle East. The tree produces seeds that are widely consumed as food. Pistacia vera often is confused with other species in the genus Pistacia that are also known as pistachio. These other species can be distinguished by their geographic distributions and their seeds which are much smaller and have a soft shell. Continual advances in crop improvement through plant breeding are driven by the available genetic diversity. Therefore, the recognition and measurement of such diversity is crucial to breeding programs. In the past 20 years, the major effort in plant breeding has changed from quantitative to molecular genetics with emphasis on quantitative trait loci (QTL) identification and marker assisted selection (MAS). The germplasm-regression-combined association studies not only allow mapping of genes/QTLs with higher level of confidence, but also allow detection of genes/QTLs, which will otherwise escape detection in linkage-based QTL studies based on the planned populations. The development of the marker-based technology offers a fast, reliable, and easy way to perform multiple regression analysis and comprise an alternative approach to breeding in diverse species of plants. The availability of many makers and morphological traits can help to regression analysis between these markers and morphological traits.
Materials and Methods: In this study, 20 genotypes of Pistachio were studied and yield related traits were measured. Young well-expanded leaves were collected for DNA extraction and total genomic DNA was extracted. Genotyping was performed using 15 RAPD primers and PCR amplification products were visualized by gel electrophoresis. The reproducible RAPD fragments were scored on the basis of present (1) or absent (0) bands and a binary matrix constructed using each molecular marker. Association analysis between molecular date (as independent variable) and morphological data (as dependent variable) was performed using multiple regression analysis to identify informative markers associated with the yield related traits. Multiple regression analysis was conducted using stepwise method of linear regression analysis option of SPSS. Student t-test was performed to assess significance difference between mean trait estimates of genotypes where specific markers were present and absent. Markers shown significant regression values were considered to be associated with the trait under consideration.
Results and Discussion: Finally 11 primers were polymorphic and a total of 56 pieces (loci) were amplified that among these, 36 segments (64.29%) showed polymorphism with an average of 5.09% per primers and the rate of this polymorphism ranged from at least 25% for AJ05 primer up to 87.5% for OPAD02 primer. Polymorphic information content ranged from 0.095 (AJ05 and OPAD14) to 0.39 (OPC05), with an average of 0.23. Stepwise regression analysis between molecular data and traits was performed to identify informative markers associated with yield component traits. Nineteen RAPD fragments were found associated with six yield related traits. Some of RAPD markers were associated with more than one trait in multiple regression analysis that may be due to pleiotropic effect of the linked quantitative trait locus on different traits. However, to better understand these relationships, preparation of segregating population and linkage mapping is necessary. Also, these results could be useful in marker-assisted breeding programs when no other genetic information is available.
Conclusion: This investigation on molecular markers associated with yield traits in Pistachio has provided clues for identification of the genotypes with higher yield value. In breeding programs selection of quality material is often a time-consuming process, and thus marker-assisted selection could be of great useful in identification of promising genotypes with high value of yield traits. Some of RAPD markers can be used for elite selection of Pistachio, particularly when no other genetic information like linkage maps and quantitative trait loci are available for the species. The applications of the RAPD approach enable us to predict positive correlation between data generated by molecular markers and studied traits. Also, the marker–trait association identification will play an important role in plant MAS/QTL breeding programs, especially in plants where genetic information such as linkage map and QTL is not available.
Research Article
Mohammad Javad Ahmadi Lahijani; Mohammad Farsi
Abstract
Introduction: Among edible mushrooms, white button mushroom is the most cultivated one around the world. Mono-spores diversity in terms of growth rate, colony type, yield and etc. is used for intra strain genetic improvement. High yielding isolates with filamentous mycelium type are screened and used ...
Read More
Introduction: Among edible mushrooms, white button mushroom is the most cultivated one around the world. Mono-spores diversity in terms of growth rate, colony type, yield and etc. is used for intra strain genetic improvement. High yielding isolates with filamentous mycelium type are screened and used for spawn production (Farsi and Gordan, 2002). Success in mushroom production largely depends on the quality of spawn produced in sterile conditions (Sanchez, 2010). Farsi and Gordan, (2004) reported that colony shape and mycelium growth type are very important factors in screening isolates in terms of mycelium growth rate and yield. To screen isolates based on their mycelium growth, solid media are among the most suitable ones (Griffin, 1994). In a study conducted to evaluate mycelium growth rate of six Morchella species on different media, PDA and MEA were known as the best ones (Kalmis and Kalyoncu, 2008). The present study was conducted in order to evaluate mycelium growth rate and yield of white button mushroom isolates in solid medium, spawn and compost media.
Materials and methods: Eighteen isolates of white button mushroom were compared on PDA (Potato Dextrose Agar), CYM (Complete Yeast Medium), spawn and compost media based on mycelium growth rate, type and class growth and yield at the mushroom research center of Faculty of Agriculture, Ferdowsi University of Mashhad, in 2014. A piece of mycelium of each isolate was placed in the center of each petri dish and was kept in 23±1°C, and the radial growth rate of mycelium was measured as two perpendicular diameters in three consecutive weeks. Mycelium growth rate on spawn and compost media was measured based on the percentage of surface coverage during the 15 consecutive days. Yield of each isolate was measured by daily harvesting of mushrooms during 35 days of experiment. Analysis of variance and means comparison of the variables were carried out using SAS software. Means analysis was performed using LSD test at 5% significance level.
Results and discussion: There were significant differences among isolates based on mycelium growth rate and yield. In PDA medium, 2200 isolate showed the fastest mycelium growth rate with 1.9 mm.day-1 and final colony diameter of 8.1 cm. were This isolate also showed the fastest mycelium growth rate on CYM medium and covering the spawn and compost media surfaces, and produced the highest yield along with A15a isolate (A15a and 2200 with 22.1 and 19.4 kg.m-2, respectively). Magnum d with mycelium growth rate of 0.7 mm.day-1 and final colony diameter of 3.1 cm showed the slowest mycelium growth rate. On average, 75% of isolates were grouped in slow mycelium growth rate class and 25% were placed in fast mycelium growth rate class. Isolates A15a, 2200, A15, M7219 and F64d showed fast mycelium growth rate. All of the isolates showed filamentous mycelium growth type and no abnormal mycelium growth type was observed. Isolate A15a with 50% coverage of compost surface during the first 5 days and 90% during the 15 days showed the fastest mycelium growth rate on this medium, followed by isolates F64d, 2200 and A15a. Normal mycelium growth rate on compost medium varied from 6-8 to sometimes 10-12 mm.day-1 (Farsi and Pooyanfar, 2011). There was a high positive correlation between mycelium growth rate and the yield component, so that isolates with faster mycelium growth rate produced higher yield. Farsi and Gordan, (2001) also reported significant positive correlation between filamentous mycelium type and yield, so that isolates with filamentous mycelium growth type and high mycelium growth rate produced higher yield. Faster mycelium growth rate is considered as a desire characteristic in mushroom cultivation due to the reduction of contamination risk of other micro-organisms (Oie, 2003).
Conclusion: There was a high significant difference among white button mushroom isolates in terms of mycelium growth rate and yield. Isolates with faster mycelium growth rate on solid medium produced higher yield. A high positive correlation was observed between mycelium growth rate on CYM and compost media, so it could be used as an appropriate medium for comparison of mycelium growth rate in vitro. As comparison of strain yield is time consuming and difficult, screening based on their growth rate on CYM is recommended.
Research Article
Hamed Doulati Baneh; Hekmat Jafari; Rasul Jalili Marandi; Rahim Abdolahi
Abstract
Introduction: The basic characteristic of modern table grape production is its adaptation to the requirements of the market aiming to improve grape quality, such as equal cluster size, equal size and shape of the berry, and equal coloration of all the berries in the cluster. Furthermore, an important ...
Read More
Introduction: The basic characteristic of modern table grape production is its adaptation to the requirements of the market aiming to improve grape quality, such as equal cluster size, equal size and shape of the berry, and equal coloration of all the berries in the cluster. Furthermore, an important attribute of the grape berry quality is seedlessness. Seedless cultivars are characterized with small berries, which can be increased by using some management techniques. Plant hormones may play an important role in the growth and development of grape berries. Gibberellic acid (GA3) is known to stimulate development of parthenocarpic fruit in grapes and other fruits. The exogenous pre-bloom application of GA3 to grapevine is commonly used to induce seedlessness, accelerate early ripening, and enhance berry size in seedless cultivars. Although there are a large number of studies on seedless grape varieties, no previous research has been performed on the effect of GA3 on the seeded grape cultivars. Differences in the types of berry set affect the growth of berries and their size. It is well known that there is an important relationship between seed development and berry growth, which has been attributed to hormones such as auxins, gibberellins and cytokinins.
Materials and Methods: To study the effects of 100 mg/L pre-bloom (7 and 14 days before blooming) GA3 application on the induction of seedlessness and some berry and cluster characteristics of three seeded Iranian cultivars, Qzl ouzum, Rish babab Qermez and Khalili Qermez, this research was conducted as a factorial experiment based on Randomized Complete Block Design (RCBD) with five replications. The vines of each cultivar were selected in the vineyard of Horticultural Research Center in West Azarbaijan Agriculture and Natural Resources Research Center, Urmia, Iran. The vines were 13 years old and bi-lateral cordon system had been used as their training system. Pollen germination test was performed at the time of flowering, and several qualitative and quantitative traits including fruit set percentage, cluster length, rachis fresh weight, number of shot berries, number of seedless berries in clusters, the average weight of seedless berries, length of pedicle, berry weight, total soluble solids (TSS) and pH were measured.
Results and Discussion: The results of the study showed that GA3 at 100 mg/L showed significant difference from control regarding pollen germination rate, fruit set percentage, length of cluster and rachis, number of shot berries, weight and number of seedless berries, length of pedicle, weight of berry and TSS. Pollen germination was reduced in those cultivars treated with GA3 but the responses of cultivars were different. Gibberellin caused an increase in cluster length, but the rate of increase in Rish baba and Qzl ouzum was greater than Khalili. In terms of inducing seedlessness in berries, GA3 caused greater effect in Qzl ouzum than Rish baba and Khalili Qermez. The greatest seedless berries weight obtained with the treatment of GA3 spray 7 days before blooming in Qzl ouzum, although the number of seedless berries in this cultivar was fewer than other cultivars. The difference in berry number per cluster between clusters receiving GA3 pre- vs. post-anthesis appeared to consist largely of seedless berries. Perhaps, GA3 stimulated non-fertilized or otherwise nonviable fruits to be retained. The longest pedicle observed in Qzl ouzum treated with 100 mg/lit GA3 14 days before blooming, while Khalili Qermez had the shortest pedicle. In all the cultivars, treatment with GA3 caused an increase in the average length of pedicle. The content of total soluble solids (TSS) in fruits treated with GA3 was higher than control. Gibberellic acid promotes cell division, stimulates earlier flowering, increases the size and yield of fruits, and induces seedlessness in seedless cultivars. The effect of GA3 depends on variety, concentration and time of application.
Conclusion: In conclusion, application of GA3 at 100 mg/lit increased fruit set and seedless berries. The increased number of seedless berries was also noticed when GA3 applied at 100 mg/L. In general, GA3 application before flowering in Qzl ouzum, Rish babab Qermez and Khalili Qermez cultivars produced shot berries and seeded berries, and repeated GA3 application after fruit set can resulted in seedless berries with an acceptable size. More research is needed to establish guidelines for the proper use of GA3 for production of seedless berries from the studied seeded cultivars.
Research Article
Roozbeh Farhoudi
Abstract
Introduction: Iran’s climate is mostly arid and semi-arid, where water availability is a major problem. Water stress substantially alters plant metabolism, decreasing plant growth and photosynthesis and profoundly affecting ecosystems and agriculture, as well as human societies. Unfortunately, water ...
Read More
Introduction: Iran’s climate is mostly arid and semi-arid, where water availability is a major problem. Water stress substantially alters plant metabolism, decreasing plant growth and photosynthesis and profoundly affecting ecosystems and agriculture, as well as human societies. Unfortunately, water deficiency is increasingly becoming a serious problem in agriculture in Iran whereas the national average annual precipitation is less than 249 mm. Recently, medicinal and aromatic plants have received much attention in several fields such as agroalimentary, perfumes, pharmaceutical industries and natural cosmetic products. Although, secondary metabolites in the medicinal and aromatic plants impressed conventionally by their genetic makeup; moreover their biosynthesis is strongly influenced by environmental factors. It means biotic and abiotic environmental factors affect growth parameter, essential oil yield and constituents. Abiotic environmental stresses like drought have the most effect on medicinal plants. In arid and semi-arid regions like south of Iran where water availability is a major limitation, using plants with low water consumption is one way to manage available water efficiently. Chamomile (Matricaria recutita L.) and chicory (Cichorium intybus) are annual plants belonging to Asteraceae family naturally widespread in west, northwest and south of Iran and their consumption has a long history in Iranian folklore medicine. Over 120 components have been identified in these plants essential oil, while, chamazulene, camphor, bisabolol oxides A and B, farnesene and ά- bisabolonoxide are the most important ones.
Materials and Methods: This study was conducted in Research Farm of Islamic Azad University, Shoshtar Branch, Iran during 2010-2011 in order to evaluate the effects of water stress levels on growth, photosynthesis and essential oil yield of German chamomile (Matricaria recutita L.) and chicory (Cichorium intybus). Two water stress levels viz. medium at 75% field capacity (FC) (I 75) and sever at 55% FC (I 55) were included in the study, while 90% FC (I 90) was taken as control. The experiment was laid out based on a randomized complete block design (RCBD) with four replications. Net plot size was 2 m × 2 m having plants density of 120 chamomile m-2 and 100 chicory m-2. Sowing was done manually on well prepared seedbed in November 2010 and plants were harvested in June 2011. Irrigation treatments were started three weeks after seed sown when seedling started their growth and development. Chamomile and chicory essential oil percentage, essential oil yield, dry weight, photosynthesis and chlorophyll content were assayed in this research.
Results and Discussion: Results showed that drought stress had significant effect on photosynthesis, chlorophyll a concentration, plant height and dry matter yield of chamomile and chicory. The Lowest flowers dry yield of chamomile and leaf dry weight of chicory obtained from severe drought stress level (47 and 195 gr m-2). The highest essential oil yield of chamomile (56.6 g m-2) and chicory (226.9 gr m-2) showed in mild drought stress treatment. Results indicated that medium drought stress increased seconds’ metabolites concentration and essential oil yield of chamomile and chicory. Important second compound in chamomile and chicory essential oil were camphor, α-pinene, β-pinene, ά-bisabolol and chamazulene. Drought stress decreased photosynthesis rate and minimum photosynthesis rate in chamomile and chicory were 9.0 mgl CO2 m-2 s-3 and 12.0 mgl CO2 m-2 s-3 under severe drought stress treatment. In chamomile the lowest chlorophyll a content showed in mild and severe drought stress treatments (1.1 and 1.2 mg g-1). Minimum chlorophyll a and b content of chicory obtained from severe drought stress treatment (0.7 and 1.02 mg g-1 respectively).Results of the study clearly elaborate that severe drought stress hampered the growth, photosynthetic rate and lowered the oil yield of chamomile, whereas medium drought stress (irrigation at 75% of FC level) improved the growth and oil productivity even more than well watered conditions. Although, severe water stress observed sizeable rise in essential oil contents but due to drastic reduction in flower or leaf dry weight, severe drought stress exhibited lowest oil yield in chamomile and chicory.
Conclusion: The results of the study clearly elaborated that medium drought stress (irrigation at 75% of FC) enhanced the essential oil productivity, while severe water stress (55% FC) decreased chamomile and chicory growth, photosynthesis rate and essential oil yield. Moreover, under drought stress quantity of chamomile and chicory oil was improved. Therefore, chamomile and chicory should be irrigated at 75% FC level to attain higher essential oil yield.
Research Article
Fatemeh Moradipour; Jamal-Ali Olfati; Yousef Hamidoghli; Atefeh Saburi; Bahman Zahedi
Abstract
Introduction: Cucumber (Cucumis sativus L.) is one of the most widely cultivated vegetables. Plant length is a quantitative trait is controlled by many genes. These traits are difficult to study due to the complex nature of their inheritance. The combining ability estimation is useful in determining ...
Read More
Introduction: Cucumber (Cucumis sativus L.) is one of the most widely cultivated vegetables. Plant length is a quantitative trait is controlled by many genes. These traits are difficult to study due to the complex nature of their inheritance. The combining ability estimation is useful in determining the breeding value of cucumber lines by suggesting the appropriate use in a breeding program. In studying combining ability, the most commonly utilized experimental approach is the diallel design. General combining ability is a measure of additive genetic action; and specific combining ability (SCA) is deviation from additivity. General combining ability is a main effect and SCA is an interaction. The aim is to determine the breeding value of the cross. Heterosis has been utilized to exploit dominance variance through production of hybrids. There are reports on positive and negative heterosis in cucumber however, there are differences between reports. This research was conducted to estimate general and specific combining ability and heterosis in cucumber inbred lines and hybrids to produce hybrids with high yield and quality.
Material and Methods: In the spring of 2014, the seven parental lines and their 21 F1 hybrid were planted at the University of Guilan, in loamy sand field. Three replications were arranged in a randomized complete block design. The sandy loam soil was prepared by plowing and disking and formed into raised beds by plowed and harrow prior to plant establishment. Rows were on 1 m centers and plants were about 25 cm apart in the row. Prior to planting 150 kg·ha-1 of nitrogen from urea and 100 kg·ha-1 of phosphorous from triple superphosphate and 80 kg·ha-1 of potassium sulfate was applied. Side dressing with the same amount of nitrogen and phosphorus occurred at 50% flowering stage. Irrigation with 250 m3·ha-1, three times weekly, was begun at plant first flowering. In each replication, 12 individuals of each line or hybrid were spaced 25 cm within a row (plot) on 1 m centers. Data were collected from 12 plants per plot of each accession. Analyses of variance (ANOVA) of data were performed and where appropriate, ANOVA was followed by LSD mean comparison of trait values. For the combining ability analysis (GCA), measurements of plants within each plot were averaged, and means were used as experimental units for analysis by the computer program Diallel.
Results and Discussion: Genotypes has significant effect on all measured characteristics. The highest plant length was related to B6 line and the lowest plant length was related to A0×B6 and B12×B6 hybrids. The highest number of lateral branch was related to B10×A11, B12×A0 and Guilan while the lowest number was related to A0, B12×B6, A15×A11. The highest plant length to first fruit was related to A4×A11 hybrids and the lowest plant length to first fruit was related to B10, B12, B10×A15 and B12×A4. The mean square of general combining ability (GCA) were significant only for plant height up to the first fruit but the mean square of specific combining ability revealed significant differences for all traits that indicated the important effects of dominance genes in inheritance of traits. Plant height up to first fruit has further general combining which reflects the non-additive genes action. The highest parent and standard negative heterosis for plant length was related to B12×B6 hybrid. This hybrid also showed the highest negative heterosis for number of lateral branch. The highest high parent negative heterosis for plant length to first fruit was related to A11×A4 hybrid while the highest standard negative heterosis was related to A0×A4 hybrid and the highest positive heterosis for this trait was obtained from B10×B12 and B12×A4 hybrids.
Conclusion: Although heterosis is affected a plant length is the primary target for increasing yield in high density cultivation, the biological complexity of this trait makes it difficult to draw meaningful conclusions in order to track individual causal elements involved in heterosis. Cucumber breeders might develop determinate or indeterminate cultivars based on high GCA for certain traits. Cucumber breeders might develop cucumber cultivars with optimal vegetative growth based on high general combining ability for their traits. The results revealed B10 and A4 lines are proposed for hybrid production with optimum vegetative growth. The hybrid obtained by crossing of B12 and B6 are proposed for cultivation with high plant density.
Research Article
Hamid Alipour; Mohammad Kafi; Ahmad Nezami; Amir Hossein Mohammadi
Abstract
Introduction: In Iran, main pistachio cultivation areas are located in the edge of desert. The major problem of these areas is the salinity of soil and irrigation water, which affects the growth and performance of plants and reduce yield.
Material and methods: In the present study, the effects of salinity ...
Read More
Introduction: In Iran, main pistachio cultivation areas are located in the edge of desert. The major problem of these areas is the salinity of soil and irrigation water, which affects the growth and performance of plants and reduce yield.
Material and methods: In the present study, the effects of salinity on growth characteristics and mineral contents of seedlings of seven pistachio cultivars and three genotypes (Akbari, Ahmad-Aghaei, Kaleh-Ghoochi, Fandoghi, Badami, Ebrahimi, Seyfadini and G1, G2 and G3 genotypes) were evaluated. The study was conducted in split plot based on randomized complete block design in three replications. The main plots were salinity levels of the irrigation water (0.6, 15 and 30 dS/m) by adding sodium chloride to tap water, and the sub plots were the pistachio cultivars. After germination of seeds in the lab, the seedlings were transplanted into new vases in the greenhouse. At 3rd leaf stage, the salinity treatments were imposed for a period of four months. At the end of the experiment, all samples were collected for growth and cation contents of shoots and roots and data were analyzed by analysis of variance and correlation method, using SAS statistical software and Duncan’s Multiple Range Test was employed at probability level of 5%.
Results and discussions: The results showed that increasing salinity levels reduced stem, root and leaf dry weight as well as stem height and diameter. Salinity also caused a reduction in leaf number and leaf area. At the salinity level of 30 dS/m, dry weights of root and leaf decreased by more than 70%. The length and diameter of seedlings were decreased by 17.2 % and 37.9 % under the mentioned condition. According to the measured growth characteristics, Akbari and Kaleh-Ghoochi, considered as fast growing cultivars, while G3 genotype and Seyfoddini cultivar were considered as slow growing cultivars. By increasing salinity, sodium and calcium concentrations in root, stem and leaf increased significantly, and the ratio of potassium to sodium decreased in the mentioned parts of the plant. Fandoghi and Kaleh-Ghoochi cultivars accumulated the highest amounts of sodium in leaf, while G1 and G2 genotypes had the lowest sodium level. An important fact is that G3 variety had minimum stem and leaf sodium content and maximum root sodium content. In contrast, Kaleh-Ghoochi cultivar had maximum leaf sodium content and minimum root sodium content. This obviously indicates that G3 variety accumulates sodium in the root and avoids sodium transmission to stem and leaf, and Kaleh-Ghoochi variety acted conversely. G2 genotype and Kaleh-Ghoochi variety contain the highest (3%) and lowest (1.4%) levels of leaf potassium. At salinity levels of 15 and 30 dS/m, the index of potassium to sodium ratio decreased by 93% and 87%, respectively, in comparison to the control salinity level (0.6 dS/m2). Generally, local genotypes of pistachio (G1, G2 and G3) showed lower sodium absorption and transport to leaf, while G3 genotype had the highest sodium content in the root and the lowest concentration of sodium in stem and leaf. G2 genotype and Ahmad-Aghaei cultivar had the highest leaf potassium to sodium ratios of 7/8 and 6/3, respectively, while Kaleh-Ghoochi cultivar had the lowest leaf potassium to sodium ratio (3/95). It seems that Kaleh-Ghoochi, Fandoghi and Akbari cultivars are relatively sensitive and G1, G2 and G3 genotypes and Ahmad-Aghaei cultivar are relatively tolerant to salinity at seedling stage. Results of correlation analysis showed a significant negative correlation between the levels of salinity and growth characteristics of pistachio. Leaf sodium content has a significant negative correlation with leaf potassium content as well as the potassium to sodium ratio in root, stem and leaf. Reduced or stunted growth of the pistachio seedlings can be a result of water stress as well as sodium and chlorine toxicities. The impaired balance of nutrient uptake through the root in salt stress conditions leads to reduced growth characteristic of the pistachio seedlings. As the salinity of the irrigating water increases, concentrations of sodium and chlorine ions in soil solution increases, therefore, balance of nutrients is impaired and the root absorption of sodium and chlorine increases and potassium uptake decreases. Hence, the concentrations of sodium and chlorine ions increased in root, stem and leaf, andpotassium concentration decreased. Salinity tolerance in many plants is attributed to non-transmission or limited transmission of sodium to aerial parts of the plant. Various pistachio cultivars acted differently in absorption and accumulation of these elements in the parts of plant. The pistachio varieties with less sodium absorption and transmission to the leaf, but more potassium absorption and transmission, increased potassium to sodium ratio in the leaf and showed more tolerance to salinity. The mechanism is not clearly recognized, perhaps sodium is re-absorbed from the xylem sap and remained in the root and stem, without transmission to leaf. A similar mechanism probably occurs in local genotypes of pistachio (G1, G2, and G3) and results in improved tolerance to salinity.
Research Article
Mahjabin Adel; Mohammad Esmaeil Amiri; Mohammad Ali Nejatian; Maryam Adel
Abstract
Introduction: Distribution of photosynthetic substances between vegetative and reproductive parts is influenced by the environmental factors as well as plant nutrition status. Therefore, application of nutrient substances (such as chelated magnesium sulfate and salicylic acid combination) can influence ...
Read More
Introduction: Distribution of photosynthetic substances between vegetative and reproductive parts is influenced by the environmental factors as well as plant nutrition status. Therefore, application of nutrient substances (such as chelated magnesium sulfate and salicylic acid combination) can influence the distribution of photosynthetic substances which in turn result in changes in allocation of photo-assimilates between vegetative and reproductive parts. Since the investigation of partitioning of photo- assimilates is complex and the interpretation of treatments effects on partitioning of substances is difficult in garden plants, this examination has been focused on external application of nutritional treatments on different organs growth by comparing the effects of salicylic acid and chelated magnesium sulfate on the allocation of photo- assimilates.
Materials and Methods: This experiment was performed in a commercial 10-year old orchard of Qazvin in 2013. Initially, 60 uniform pears (cv. Louise Bonne) which were infected to fire blight disease were selected. Before treatment imposing, agronomic practices such as removing and pruning infected shoots were applied. Treatments were combination of salicylic acid and chelated magnesium sulfate at different levels, which were applied on foliage under the conditions of neutral pollution to fire blight. In the present research, vegetative parameters (current shoot growth, leaf weight, leaf area, relative water content and so on) and reproductive parameters (length: diameter ratio and density of fruit and so on) were measured.
The fully expanded leaves were collected randomly from each replicate. After washing the samples were weighed and these values referred to as initial readings (fresh weight). Then, the leaf samples were placed in distilled water for 24 h in the dark at room temperature. The turgid leaves were blotted dry and weighed (saturation weight). After weighing, the material was oven-dried at 70 °C for 24 h. Relative water content (RWC) of the leaves was appraised as described by Ritchie and Nguyen (19) using the following formula:
RWC (%) = [(f. wt. – d. wt.) / (t. wt. – d. wt.)] × 100
Where f. wt, d. wt and t. wt are fresh weight, dry weight and turgid weight, respectively.
Diameter and length of fruit were measured by nondestructive method (on the tree) and by using digital caliper in the places of maximum length and maximum width diameters, and length: diameter ratio from the division of these two parameters. Fruit weight was estimated by digital scale (0.01 g) and its volume by the difference of the water level of scaled column, and then fruit density was calculated by using formula d=M/V.
In order to estimate the parameters of leaf area, specific leaf area and specific leaf weight, leaf area meter and oven were used. To evaluate the effect of the treatments on decrease or increase current shoot growth, measuring shoot length was reported by tape measure according to centimeter.
Results and Discussion: The results indicated that the most amount of specific leaf weight was allocated in chelated magnesium sulfate (0.5 and 0.7 g: 1000 ml) treatments and the least amount was belonged to the control group. The extent of changes in leaf area was between 28.17 to 44.33 cm2, were recorded to control group (without water) and salicylic acid (0.1 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml), respectively. The minimum and maximum of specific leaf area were ranged between 44.14 to 59.40 cm2 and belonged to control group (without water) and salicylic acid (0.1 g: 1000 ml), respectively. The most current shoot growth was observed in control group (without water) and the least quantity was in chelated magnesium sulfate (0.5 g: 1000 ml). The minimum and maximum of fresh weight of leaf was changeable between 1.513 to 1.94 g were recorded to control group and salicylic acid (0.1 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml), respectively. The most and the least content of leaf relative water were observed to salicylic acid (0.5 g: 1000 ml) plus chelated magnesium sulfate (0.5 g: 1000 ml) and salicylic acid (0.5 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml), respectively. The extent of changes in fruit specific gravity was changeable between 0.72 to 0.97 g to cm3. The maximum amount of fruit specific gravity was seen in salicylic acid (0.5 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml) and the minimum amount was in salicylic acid (0.5 g: 1000 ml) treatment. The conformity of the maximum current shoot growth and leaf fresh weight with the minimum leaf dry weight, leaf area, specific leaf area and specific leaf weight to control group and control group (without water) can declare the effect of treatment substances on the allocating manner of substances in different organs in plants and its stimulating effect on vegetative indexes that is not observable in the lack of treatment substances. The allocation of the most fruit specific gravity and also the least leaf relative water content and the least fruit length: diameter ratio to salicylic acid (0.5 g: 1000 ml) and chelated magnesium sulfate (0.7 g: 1000 ml) can confirm the opposit relation among these parameters in the way of substances allocation and the effect of above treatment on this opposit relation. Denser fruits have fewer growth rather than types with the more blank space and receive a more carbohydrate from the tree rather than their weight. The decrease of relative water content of leaf can also be explained in the direction of the more absorption of carbohydrate by fruit as a strong sink. In other words, the existence of fruit as a strong sink in favorable conditions for photosynthesis (with paying attention to the high vegetative indexes) can prevent gathering water in chloroplast and cause an increase of fruit specific gravity.
Also, the allocation of the most specific leaf weight and the least fruit length: diameter ratio and the least current shoot growth to chelated magnesium sulfate (0.5 g: 1000 ml) express the positive role of sulfur in aforesaid concentration on stimulating leaf growth and its negative role in stimulating growth of shoot and fruit that somehow points on the effect of treatment substances on the allocation of substances (elaborate sap) to different organs. The sulfur compounds can cause preventing gibberellin synthesis and the decrease of internode length, like other growth retardants.
The maximum fruit length: diameter ratio was belonged to salicylic acid (0.1 g: 1000 ml) and chelated magnesium sulfate (0.7 g: 1000 ml). Salicylic acid (0.1 g: 1000 ml) treatment induced maximum amounts of fruit length and diameter to itself that confirms the positive role of salicylic acid in stimulating growth in stress conditions (biotic stress derived from Erwinia amylovora). The significant negative correlation (p
Research Article
Ghahraman Bagheri; Bahman Zahedi; Reza Darvishzadeh; Ahmad Hajiali
Abstract
Introduction: Pepper is one of the most important vegetables in the world that belongs to the family of Solanaceae. It is used as a food flavoring, coloring agent and a pharmaceutical ingredient in different innovative ways. Capsicum annuum is one of the five cultivated species in the genus and the ...
Read More
Introduction: Pepper is one of the most important vegetables in the world that belongs to the family of Solanaceae. It is used as a food flavoring, coloring agent and a pharmaceutical ingredient in different innovative ways. Capsicum annuum is one of the five cultivated species in the genus and the others are C. baccatum L., C. chinense, C. frutescens and C. pubescens. While C. pubescens and C. baccatum are morphologically quite distinct, C. annuum, C. chinense and C. frutescens show evidence of parallel evolution for a variety of plant and fruit morphological characteristics as a result of similar regimens of human selection. The near continuous overlapping in morphological traits among these three species led various authors to recognize them as a complicated species. Within complex, taxa are differentiated from one another based primarily on differences in corolla color, the presence or absence of a calyx constriction and the occurrence of multiple pedicels/node.
Materials and Methods: This research was conducted to evaluate genetic diversity in pepper genotypes. Morphological traits of 42 genotypes were investigated in rectangular lattice 6×7 with three replications in two separate experiments at West Azerbaijan research institute. Analysis of variance was conducted by using SAS, SPSS and MINITAB softwares. 14 traits including length and width of fruits, thickness of fruit wall, width of plant canopy, length of shoots, length of corolla, fruits fresh and dry weight, SPAD, photosynthesis, yield, vitamin C, TSS and pH were assessed according to the International Board for Plant Genetic Resources (IBPGR) descriptor. Solid contents (TSS) were assessed by using refractometer, pH by using pH meter, and fruits fresh and dry weight by using a digital scale. For measuring vitamin C content, 3-10 g of the fruit tissue (pericarp and pulp) was homogenized and 100 mL of distilled water were added. Then 10 mL of sulfuric acid 20%, 1 mL of 0.01 N potassium iodide, 1 mL of 1% starch were added to the solution and then for titrating, 0.01 N potassium iodide was used.
Results and Discussion: Analysis of variance showed significant differences (at 1% level) among pepper genotypes, in terms of width of fruits, fruit wall thickness, yield, plant height, shoots diameter, length of shoots, and dry weight of fruit, TSS and vitamin C. But there were no significant difference between pH, SPAD and photosynthesis. The highest heritability was observed in length and width of fruits, fruit wall thickness, fruit pedicel length, yield, dry and fresh weight of fruits, and the lowest heritability obtained in SPAD and pH. Phenotypic variation coefficient was higher than genotypic variation coefficient for all traits, indicating the significant effects of environmental conditions. The maximum phenotypic correlation obtained between fruit fresh and dry weight (r=0.95) and also observed between fruit fresh weight and fruit wall thickness. Cluster analysis with Ward method classified studied landraces into six different groups. The highest distance was observed between groups four and five. This result showed that the maximum expected heterosis could achieve from crosses between genotypes from groups four and five.
Conclusions: High genetic variation was observed among pepper genotypes that could be helpful for morphological traits studies and to improve superior genotypes in next breeding programs.
Research Article
Gholamhossein Davarynejad; Seyedeh Faezeh Taghizadeh; Javad Asili
Abstract
Introduction: Phenolic compounds have an ability to scavenge free radicals and cause the balance of reactive oxygen species (ROS) in our body. This balance prevents atherosclerosis, coronary heart and cancer diseases. Butylated hydroxyl toluene (BHT) is a well-known synthetic antioxidant, which is restricted ...
Read More
Introduction: Phenolic compounds have an ability to scavenge free radicals and cause the balance of reactive oxygen species (ROS) in our body. This balance prevents atherosclerosis, coronary heart and cancer diseases. Butylated hydroxyl toluene (BHT) is a well-known synthetic antioxidant, which is restricted to be used due to its probable toxic effects. Therefore, replacement of synthetic antioxidants with plant materials with high amounts of antioxidant activity, which protect the body from free radicals and many diseases caused by lipid peroxidation, is an appropriate option. ZiziphusjujubaMiller is one of the forty species belonging to Rhamnaceae family, which produces a great deal of industrial raw materials for horticultural, ornamental, food, and pharmaceutical industries. Antioxidants can be extracted by various solvents and extraction methods. Solvent extraction is the most common method used for separating natural antioxidants. Solvent properties undoubtedly play a key role in the extraction of antioxidative compounds. The type and yield of antioxidant extracted have been found to vary as affected by the solvent properties such as polarity, viscosity and vapor pressure. Therefore, it is difficult to develop a unified standard method for the extraction of antioxidants from all plant materials.
Materials and Methods:
Plant materials Fresh fruits were collected from Birjand, Iran, in late summer 2014. The samples were air dried under the shade at room temperature. Dried fruits were ground by using a mortar and pestle and were separately extracted by distilled water and organic solvents such as methanol, ethanol and acetone (50%, 90% and100% (v/v)). After filtering through the Whatman paper #3 and removing the solvents (using a rotary evaporator (BUCHI V-850)) and water (using a freeze dryer, (OPERON, FDB-5503, Korea)), the dried extracts were stored in refrigerator for further analysis.
Determination of Total Phenolic Content (TPC) Samples were measured for TPCs colorimetrically using the Folin-Ciocalteu method with modification. Absorbance was read at 725 nm against blank using UV-Visible spectrophotometer (Cecil. UK.). A calibration curve was prepared using a standard solution of Gallic acid (0.2-1mg/ml). Results were expressed as mg Gallic acid/g dry extract (mg GA/g DE).
Determination of Total Flavonoid Content (TFC). TFC was determined using the method of Huang et al. (13) with minor modifications. Absorption was measured at 430 nm using UV-VIS spectrophotometer (Cecil. UK.). TFC was determined using a standard curve with quercetin as the standard, and expressed as mg of quercetin equivalents (CE)/g dry extract (mg QE/g DE).
Determination of Total Anthocyanin Content (TAC). TAC was measured using a spectrophotometric differential pH method. Its absorbance was read at 510 and 700nm. Results were expressed as milligrams of cyanidin-3-glucoside (CY.) equivalents per g of dry extract.
Determination of Total Tannin Content. For determination of tannins in the sample extracts, vanillin–HCl method was used. The absorbance was read at 500 nm using UV–vis spectrophotometer. The content of tannins in the sample was expressed as mgcatechine equivalent (CE)/100g sample.
Determination of Antioxidant Activity. Antioxidant activity of the samples was determined using DPPH (2, 2-diphenyl-1-pic-rylhydrazyl) radical scavenging activity and ferric reducing antioxidant power (FRAP). In the presence of antioxidant, FRAP assay reduced Fe3+-TPTZ (2, 4, 6-tris (2-pyridyl)-5-triazine) complex to Fe2+ - TPTZ at low pH. The absorbance of the mixture was measured by using spectrophotometric ally at 595 nm. The effect of antioxidant on DPPH radical was thought to be due to their hydrogen donating ability or radical scavenging activity. DPPH assay expressed as IC50 and percentage inhibition. Lower IC50 value indicates higher antioxidant activity.
Results and Discussion: Efficiency of different solvent extractions depends on the matrix of plant materials as well as the type of extractable compounds. The correct selection of solvent can improve the extraction yield of antioxidants from plants matrices considerably. For this reason, in the present study, some selected types of solvent showed different results. For extraction of total phenol and flavonoid compound, acetone 50% was the best yield. In methanolic extract (50, 100%), the highest amounts of anthocyanin and total tannin were reported. In all extracts, water had the least efficiency in comparison with other solvents. High correlation was observed in total phenolic content and antioxidant activity which was determined by DPPH and FRAP assay. Acetone 50% was the most potent for scavenging free radicals and reducing a ferric-tripyridyltriazine, Fe (III)-TPTZ, complex to ferrous, Fe (II) in all extracts.
Conclusions: The results of the present study indicated that polarity, selectivity, viscosity, and vapor pressure are important physicochemical properties that should be considered when selecting a suitable solvent for the extraction of bioactive compounds from plant materials.
Research Article
Hassan Farhadi; Majid Azizi; Seyyed Hossein Nemati
Abstract
Introduction: Fenugreek (Trigonalla foenum-graecum L.), an annual herbaceous plant belonging to the Coleoidea (Fabaceae) family, has numerous medicinal properties such as decreasing blood glucose, laxative, appetizer, mucus, antipyretic and increasing the amount of milk during lactation . Among the most ...
Read More
Introduction: Fenugreek (Trigonalla foenum-graecum L.), an annual herbaceous plant belonging to the Coleoidea (Fabaceae) family, has numerous medicinal properties such as decreasing blood glucose, laxative, appetizer, mucus, antipyretic and increasing the amount of milk during lactation . Among the most important problems in arid and semi-arid regions, drought stress or water shortage will have negative effects on plant growth. Drought stress occurs mostly because of reducing water availability in the soil. This may be due to excessive water loss or absorption problems, or both of them. One of the major factors limiting germination, which occurs in more arid and semi-arid regions, is salt stress. The study was done to evaluate germination of four Iranian population of fenugreek (Amol, Tabriz, Sari and Mashhad) under drought and salinity stresses.
Materials and methods: To investigate the effect of salinity and drought stresses on germination and seedling growth characteristics of native landrace fenugreek, two separate experiments were conducted in a Completely Randomized Design with three replications in Seed Laboratory of University of Mashhad in 2014. The experiment treatments consisted of four levels of salinity (0, 60, 120, 180 mM) that was induced by different concentrations of sodium chloride and drought stress induced by polyethylene glycol 6000 (PEG 6000) at four levels (0, -3, -6 and -9 Bar) with three replications. The drought stress levels were simulation by polyethylene glycol 6000 and using the Michel and Kaufmann formula. Distilled water was applied as control. Iranian seed population of fenugreek were purchased from the city of Amol, Tabriz, Sari and Mashhad then the seeds were washed with sodium hypochlorite (3 % v/v) for two minutes for disinfestation and washed three times with distilled water. On the twelfth day of experiment, seedling traits such as plumule and root length and weight in Petri dishes were measured.
Results and Discussion: The results of ANOVA showed that salinity and drought stress significantly (p≤0.01) affect germination process. The results of the means comparison confirmed that fenugreek germination in all seed population was reduced by increasing salinity levels. The lowest germination was detected under 180 mM salt stress in “Tabriz” population (12.04%), while the highest germination (95/26%) was calculated in “Mashhad” population at control. Seeds of “Mashhad” population in comparison to other population showed higher germination at other salinity levels. Germination rate also was significantly affected by salinity (p≤0.01). Decreasing of germination rate in fenugreek population of Amol, Tabriz, Sari and Mashhad under 180 mM salinity stress in comparison to control (0 mM) were 84/62, 87/80, 85/93, 82/59, respectively. Mashhad and Amol (second order) populations showed more germination rate stability after changes in salinity levels. The results of analysis of variance from this study showed that interaction effect of salinity and population significantly (p≤0.05) affect root length of the fenugreek. The root length of Mashhad and Amol populations were more stable at high level of salinity. Other researcher also reported that the root length decreased after salinity treatments (10, 13). Salinity stress affect water absorption by seed and decreasing Amylase and lipase activity caused degradation of stored material in seeds and then decreasing root length (23). Salinity, population and interaction between these factors significantly (p≤0.01) affected length of plumule. The results showed that Mashhad population had the highest and Tabriz revealed the lowest length of plumule. Interaction effects of treatments on seedling dry weight showed significant (p≤0.01) differences. Mashhad in comparison to the other populations had the highest seedling dry weight as 9.26, 8.10, 7.22 and 3.6 mg/seedling at different salinity treatments (0, 60, 120, 180 mM), respectively.
Interaction effects of drought stress and population on germination percentage was significant (p≤0.01). Mashhad and Amol (second order) populations were the best populations. At the highest level of drought stress (-9 Bar), these two populations had the lowest decrease in germination percentage. The mechanism of the results was the same as salinity which explained in above. According to the results of analysis of variance (ANOVA), all treatments and all interaction had significant effect (p≤0.01) on germination rate. The Mashhad and Sari populations were more tolerant than other populations against drought stress examined as germination rate as concerned. Analysis of variance showed that the simple effects of drought stress and population on root length were significant at one percent but interaction effect of drought stress and population was not significant statistically. The root length was in the range of 26.78 to 50.29 mm in the tested population. Mashhad population was more tolerant against drought stress in comparison to the other tested populations. Analysis of variance showed that simple effect of drought and population were significant (p≤0.01) on this trait but their interaction was not significant. Length of plumule mean comparison showed that the traite was in the range of 21.74 to 43.31 mm in Tabriz and Mashhad populations, respectively.Acoording to the length of plumule,Mashhad population in comparison to other tested populations under drought stress was tolerant . The water potential (drought stress), population and interaction between them showed significant effect (p≤0.01) on seedling dry weight. Among the evaluated population the Mashhad population was tolerant to drought stress when seedling dry weight was concerned. The highest correlation coefficient (r=0.96) was detected between germination percentage and root length and in second order the correlation coefficient between germination percentage and seedling dry weight was 0.93. The lowest correlation coefficient (0.61) was observed between germination rates and seedling dry weight.
Conclusions: The decline in germination percentage, germination rate, root length, shoot length and dry weight of seedlings with increased water osmotic potential in Mashhad population was less than other evaluated populations. Seed germination rate was more sensitive than seed germination percentage in both salt and drought stress therefore this trait is a suitable criterion for screening of tolerant population for future breeding purpose. The order for tolerance to salinity and drought stress in evaluated population was Mashhad, Tabriz, Sari and Amol.
Research Article
Mohammad Salahifarahi; Faramarz Sayyedi; Hadi Sheikhvesi
Abstract
Introduction: Watermelon, originated from warm regions of Africa, is one of the most important vegetable crops used as human food, forage and for producing alcohol. The area under its cultivation in our province was 1031 ha as irrigated and 3829 ha as rainfed. The average fruit yields under above-mentioned ...
Read More
Introduction: Watermelon, originated from warm regions of Africa, is one of the most important vegetable crops used as human food, forage and for producing alcohol. The area under its cultivation in our province was 1031 ha as irrigated and 3829 ha as rainfed. The average fruit yields under above-mentioned conditions were 23784 and 14888kg ha-1, respectively. Watermelon fruits suffer from a nutritional disorder that is attributed to shortage of calcium in developing fruits. The adsorption and uptake process of calcium by plants is comprised of three main stages; the first stage is passing through root cortex into xylem, the second one is its transport within xylem, and the last one is its distribution into leaves and fruits. Plants obtain calcium preferably from soil solution. Calcium moves upward in apoplastic pathways (with transpiration flow), and reaches different organs of the plants through xylem. Blossom-end rot (BER) is a nutritional disorder of watermelon, tomato and pepper that is caused by a shortage of calcium in enlarging fruits. Blossom-end rot of watermelon commonly occurs in our province when fruits are growing rapidly. BER is frequently seen in watermelon genotypes with long fruits, Charleston gray type in particular. Calcium requirement increases at rapidly developing stage of fruit. BER might happen as a result of increased demand of blossom-end rot of fruit (rapidly growing section of the fruits) for calcium. It can occur even when there is abundant calcium in the soil, because demand exceeds supply. Since fruits do not transpire as much as leaves, less calcium is deposited when calcium containing water is transpired, resulting in a localized calcium deficiency in the fruit.
Materials and methods: In order to investigate the effects of foliar application of calcium on BER of watermelon, an experiment was carried out at the agricultural research station of Gonbad, Gonbad-e Qabus, Iran, in 2008. The soil of the experiment site was calcizerol, thermic. The soil was river alluvial plain type and the slope was moderate .The soil was not saline and PH was slightly alkaline. The amount of phosphorus, potassium, iron, boron, and calcium were sufficient but the amount of available zinc was low. The experiment was carried out in a factorial based on randomized complete block design (RCBD) with two factors and three replications. The first factor was two watermelon cultivars (Charleston gray and Charlie), and the second factor was four levels of calcium (0, 3, 5 and 8 gl-1 of calcium chloride). Each plot consisted of four ten-meter long rows. Row and within-row distances were 3 and 0.75 meters, respectively. Three seeds were planted in each hill, and they were thinned to one seedling at first hoeing when they were completely established. Irrigation was applied six times in furrows to avoid moisture stress. Foliar application of calcium was initiated before fruit set and applied with fifteen-day intervals afterwards. Number of healthy fruits, mean fruit weight, and number of fruits affected by blossom-end rot were counted from the two inner rows discarding the first and last plants of the rows. Brix was determined using a hand refractometer (OSK 7926). The data obtained was analyzed by using SAS.
Results and discussion:The effect of foliar application of calcium and genotypes were not significant for fruit length. The interaction of genotype and calcium did not significantly affect fruit length. Calcium application did not have any effect on the length of blossom-end rot affected fruits. There were not any differences between the genotypes studied. These findings were in contrast with those of some other researchers, who reported enhanced fruit length by calcium application. Brix (soluble solid content) is an important trait in watermelon, so that an increase in it raises the marketability of the product. Brix was not significantly affected by calcium, genotypes, and their interaction. The results of analysis of variance showed that fruit rind width of the genotypes was not affected by calcium, whereas calcium and genotype interaction significantly affected fruit rind width at 0.05 probability level. These findings were consistent with those of some other researchers. Fruit yield was not significantly affected by calcium. The effect of calcium on the number of fruits affected by blossom-end rot disorder was significant at 0.01 probability level, while the effect of genotype and calcium interaction on this trait was not significant. The average number of fruits affected by BER were 1667, 1144 and 588 per hectare at 0, 3, 5 and 8 gl-1calcium chloride, respectively. These findings were consistent with those reported by some other researchers.
Conclusion We concluded that under our experiment's conditions, calcium foliar application was ineffective in improving watermelon fruit yield, but it was promising in decreasing blossom-end rot, which reduces marketability of the fruit.
Research Article
Rozita Khademi Astaneh; Seyyed Jalal Tabatabaie; Sahebali Bolandnazar
Abstract
Introduction: Selenium is a non-metallic, rare chemical element and essential for many organisms but this element is not mentioned as an essential element for plants. Due to its presence in antioxidant defense systems and hormonal balance, selenium is known to be necessary in human and animal health ...
Read More
Introduction: Selenium is a non-metallic, rare chemical element and essential for many organisms but this element is not mentioned as an essential element for plants. Due to its presence in antioxidant defense systems and hormonal balance, selenium is known to be necessary in human and animal health Plants exhibit a variety of physiological responses to selenium.Some species accumulate large amount of selenium, while many plant species are sensitive to presence of large amounts of selenium in soil and water. The mean, the maximum and tolerance level of selenium required for humans is 45, 55 and 400 micrograms, respectively (Dietary Reference). but acute toxicity level in animals are found with a concentration of 1000 ppm. Plants absorb and storage selenium in chemical form and concentration depends on pH, salinity and calcium carbonate content. High contents of selenium reduce plant growth and plant dryness, however in some plants low selenium concentrations improved growth and increase stress resistance by maintenance of chloroplast enzymes. Positive response to the use of selenium were mentioned in lettuce, potato, mustard, crap, darnel, soybean (Glycinemax L), potatoes and green tea leaves. Research has shown that there is a positive relationship between selenium concentration and glutathione peroxidase activity, which is a reason to delay aging and increase growth of aging plants. The results of this study had shown that the application of selenium treatments increased leaf area of plants and, consequently, the higher availability of asmilates, can increase plant growth. The results of the studies also indicated that all vegetative characteristics of plants are increased due to the concentration of selenium and the accumulation capacity of plants affected by selenium application. Since there is no research on the effect of selenium on cabbage, it seems that the use of this element can affect the growth and development of this plant.
Materials and Methods: This experiment was tested in a controlled condition hydroponic greenhouse of Horticulture Department, College of Agriculture, University of Tabriz, The greenhouse was covered with polyethylene monolayer and equipped with a cooling and fogging systems to control the temperature in the warm months and humidity, respectively. Daily temperatures were setted3 ± 20 3 ± 16. Seeds of Gemmifera varieties brussels cabbage weregerminated in petri dishes. Seedlings were transferred to the plastic cups (to the floating system) with perlite in four leaf stage. . Plants root system were floated in solution. Modified Hoagland nutrient solution (Table 1) was prepared (12 liters per container with 40 and 32 cm height and diameter, respectively.
Results and Discussion: Results of vegetative Brussels sprouts button showed that selenium significantly increased leaf, stem and root dry weight, leaf number and leaf area. Leaf area, leaves, stems and roots fresh and dry weight increased with increasing selenium up to 8 mg L- but then decreased due to a high concentration of selenium toxicity. There were no significant difference in the treatments on stem length, stem diameter. Number of buds was significantly (P≤0.05) affected by selenium treatments and the highest number of sprouts were in two levels of 8 and 16 mg selenium per liter, respectively. Yield and shoot dry weight showed a significant increase (at 1 percent) with increasing levels of selenium,.Conclusions Plants yield significantly (P≤0.01) affected by selenium treatments, so that selenium concentration in the nutrient solution increased from 0 to 8 mg L-1increased yield and reduced afterward. The maximum yield was observed at a concentration of 8 mg L-compared with control. Based on the findings of this study, selenium concentration can be up to 8 mg L-1 in order to improve plant growth to nutrient solution.
Research Article
Hassan Hasani Jifroudi; Mehdi Mohebodini; Behrooz Esmaielpour; Esmaeil Chamani
Abstract
Introduction: Fenugreek (Trigonella foenum- graecum) is a medicinal plant extensively distributed in most regions of the world. Fenugreek is an annual plant from the family of papilionaceae, leguminosae. Fenugreek leaves and seeds have been used extensively to prepare extracts and powders for medicinal ...
Read More
Introduction: Fenugreek (Trigonella foenum- graecum) is a medicinal plant extensively distributed in most regions of the world. Fenugreek is an annual plant from the family of papilionaceae, leguminosae. Fenugreek leaves and seeds have been used extensively to prepare extracts and powders for medicinal uses. Its root, leaf and seed contain a number of important medicinal compounds such as polysaccharide, galactomannan, different saponins such as diosgenin, yamogenin, mucilage, volatile oil and alkaloids such as choline and trigonelline. Plant tissue culture is fundamental to most aspects of biotechnology of plants. Establishment of an efficient callus induction and direct regeneration protocol is an essential prerequisite in harnessing the advantage of cell and tissue culture for genetic improvement. For the successful application of the tissue culture technique in plant breeding, callus induction and plant regeneration potential of each plant must be determined. The present study was performed in order to determine the optimum concentration of plant growth regulators (IBA + TDZ) for producing of in vitro plantlet using cotyledon and hypocotyl as an explant for two different Iranian genotypes (Ardestani and Neyshabouri).
Materials and Methods: In this investigation, Ardestani and Neyshabouri genotypes were used for callus induction and direct shoot regeneration. The medium used in this investigation was MS (Murashige and Skoog) basal medium. Then seeds were germinated on MS medium. For callus induction and direct shoot regeneration, cotyledon and hypocotyl explants were excised from 8-day-old sterile seedlings and cultured on MS medium containing various concentrations of IBA and TDZ. In this experiment, two combinations (TDZ + IBA) were used. In the first composition, IBA had four levels (0, 0.1, 0.3, 0.5 mg l-1) and TDZ had five levels (0, 0.2, 0.4, 0.6, 0.8 mg l-1) and in the second composition, IBA had four levels (0, 0.05, 0.1, 0.15 mg l-1) and TDZ had seven levels (0, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45 mg l-1).The experimental designs were factorial based on completely randomized design with four replications. Cultures were incubated at 25° C ± 2 with a 16/8 hour (day/night) photoperiod and an irradiance of 1500 LUX using Sylvania cool white fluorescent tubes. The percentage of callus induction, direct shoot regeneration and average weight of callus were calculated for cotyledon and hypocotyl explants. All Data were analyzed using SPSS16, and mean comparisons were performed with duncan’s multiple range test (P < 0.05).
Results and Discussion: According to our results, explants cultured on MS basal medium without plant growth regulators (control) produced no callus. However, after two weeks, callus formed in both of Ardestani and Neyshabouri genotypes from cotyledon and hypocotyl explants in the presence of IBA + TDZ plant growth regulators in most of the combinations. In hypocotyl explants of Neyshabouri genotype, the highest callus induction was obtained from the medium containing 0.15 mg l-1 IBA + 0.45 mg l-1 TDZ (96.87%). Various important factors such as genotype, source of explants and plant growth regulators significantly influence direct regeneration. Direct regeneration was obtained from hypocotyl explants for Neyshabouri genotype in combination IBA + TDZ. The highest percentage of direct shoot regeneration was observed in MS medium containing 0.05 mg l-1 IBA + 0.35 mg l-1 TDZ in hypocotyl explants of Neyshabouri genotype (37.5%). Direct shoot regeneration requires plant cells to undergo dedifferentiation which is known to be affected by not only exogenous plant growth regulators but also endogenous content of the hormones. Different tissues may have different levels of endogenous hormones and, therefore, the type of explant source would have a critical impact on the regeneration success. In our study, when cotyledon and hypocotyl explants were compared, it was clear that hypocotyl explants were much more productive for direct shoot regeneration than cotyledon explants.
Conclusions: Callus induction and direct shoot regeneration are as in vitro tissue culture methods. Plant growth regulators and types of explant and genotype are the most important factors for callus induction and direct shoot regeneration phases. Therefore, optimization of these factors is essential to establish a high frequency of callus induction, direct shoot regeneration and gene transferring to this plant. According to the results of this investigation, it is recommended to apply plant growth regulators that were used in this study for other landraces of fenugreek cultured in Iran and select the best genotypes in response to tissue culture conditions for using in future studies.
Research Article
Mohammad Behzad Amiri; Parviz Rezvani Moghaddam; Mohsen Jahan
Abstract
Introduction: In recent years, the effect of ecological inputs on soil properties and plant growth characteristics has received renewed attention. Although the utilization of mineral fertilizers could be viewed as the best solution in plant productivity, this approach is often inefficient in the long-term ...
Read More
Introduction: In recent years, the effect of ecological inputs on soil properties and plant growth characteristics has received renewed attention. Although the utilization of mineral fertilizers could be viewed as the best solution in plant productivity, this approach is often inefficient in the long-term in many ecosystems due to the limited ability of low-activity clay soils to retain nutrients. Intensive use of chemical fertilizers and pesticides in agricultural systems is also known to have irreversible effects on soil and water resources. Maintenance of soil fertility as a permanent bed for continuous production of agricultural products is one of the most important issues affecting the sustainability of food production. In order to achieve healthy food production, application of ecological inputs such as soil amendments and bio-fertilizers is inevitable. Humic substances are a group of heterogeneous molecules that are bonded together by weak forces; therefore, they have a high chemical stability. This material included 65 to 80 percent of total soil organic matter. Application of bio-fertilizers is an appropriate alternative of chemical fertilizers to enhance soil fertility. In fact, bio-fertilizers include different types of free living organisms that convert unavailable nutrients to available forms and enhance root development and better seed germination. Mycorrhiza arbuscular fungi are coexist microorganisms that improve soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Echium amoenum is a perennial plant belongs to Boraginaceae family. This plant is native of North of Iran. Petal extract of E. amoenum have sedative, diaphoretic, anti-inflammatory and anti-depressant effects. These plants are wild perennial herbs and known in Iran as oxtongue. It is one of the most important medicinal plants in Iranian traditional medicine. Petals of Iranian oxtongue have been advocated for a variety of effects such as demulcent, anti-inflammatory and analgesic, especially for common cold, anxiolytic, sedative and other psychiatric symptoms including obsession in folk medicine of Iran. Despite many research on the effects of organic acids and bio-fertilizers on different crops, there is scarce information on the effects of these factors for many medicinal plants. Therefore, in this study effect of organic acids and bio-fertilizers on morphological characteristics and yield of Echium amoenum in a low input cropping system was studied.
Materials and methods: In order to evaluate the effects of soil amendments and different bio-fertilizers on morphological characteristics and seed yield of Echium amoenum, an experiment was conducted based on randomized complete block design with three replications during 2011-2013 growing seasons, at the Research Farm of Ferdowsi University of Mashhad, Iran. Treatments were eight different types of soil amendments and bio-fertilizers concluding: 1) Humic acid, 2) Fulvic acid, 3) Nitroxin® (Azotobacter spp. and Azospirillum spp.), 4) Biophosphorous® (Bacillus sp. and Pseudomonas sp.), 5) Biosulfur® (Thiobacillus spp.), 6) Mycorrhiza (Glomus mosseae), 7) Mycorrhiza (Glomus intraradices), and 8) no fertilizer as control.
Result and Discussion: The results showed that mycorrhiza species increased flower yield compared with control, as the flower yield in treatments of G. mosseae and G. intraradices were 24 and 11 percent more than control, respectively. Soil amendments and different bio-fertilizers increased the number of flower cycle per plant compared with control. Although the effect of biophosphorous® was more pronounced, as the number of flower cycle per plant increased from 342 to 1322 cycles in control and biophosphorous® , respectively. Humic acid treatment increased seed yield, biological yield, seed weight and seed number per plant by 82, 66, 63 and 66 percent compared with control, respectively. It seems that different species of mycorrhiza improved morphological characteristics and yield of Echium amoenum, because of better conditions to absorption and transportation of nutrient to the plant. It has been reported that organic acids provide favorable conditions for plant growth and development through improvement of physical, chemical and biological properties of the soil. Therefore, it could be concluded that improvement of most studied traits in the present study was as a result of use of organic acids.
Conclusions: Generally, our results showed that organic acids and biological fertilizers had positive effects on most of studied criteria. The highest flower and seed yields were obtained from G. mosseae and Humic acid treatments, respectively.
Research Article
Farnaz Moghadami; Khodayar Hemmati; Vahid Akbarpour
Abstract
Introduction: Citrus is in the first rank in the world with respect to production among fruits. They are grown commercially in more than 50 countries around the world. Several factors such as rootstock, nutrition and irrigation regimes, cultivation design and etc. may affect the promotion of quality ...
Read More
Introduction: Citrus is in the first rank in the world with respect to production among fruits. They are grown commercially in more than 50 countries around the world. Several factors such as rootstock, nutrition and irrigation regimes, cultivation design and etc. may affect the promotion of quality and quantity of fruits. Lemon fruits are among the most valuable functional diets shown to lower oxidative-related disease risks, particularly cardiovascular disease. A well-documented characteristic of these fruits is the accumulation of high amounts of glycoside flavonones, named hesperidin in the fruits. Several recent studies have demonstrated that the cytoprotective action of citrus fruits is enhanced by the presence of antioxidants including vitamin C, phenolics, carotenoids and flavonoids. Hesperidin and its metabolites significantly have been found to lower the total cholesterol and triglyceride concentrations in plasma. Hesperidin acts as a chemopreventive agent against colon carcinogenesis induced by azoxymethane. Lemons are one of the citrus species having many medicinal effects owing to their secondary metabolites. Flavonoids are a part of aromatic polyphenols having different biological actions such as antioxidant activity, anti-cancer, anti-sensation and etc. Hesperidin is one of the abundant secondary metabolites belonging to flavonoids in citrus, which is effective in treating many diseases.
Materials and Methods: In order to investigate the effect of lemon fruits (Citrus lemon cv. Cluster, C. lemon cv. Lisbon and C. lemon cv. Eureka) tissue type and harvesting time on the flavonoids hesperidin content, this experiment was carried out. Thus, this research was conducted in a factorial arrangement on the basis of completely randomized design with three factors: tissue type (Flavedo, Albedo and Flesh), harvesting time (45, 75, 105 and 135 days after full bloom) and three lemon cultivars (Cluster, Lisbon and Eureka) with three replications. Studied trees in Kotra Research Station were planted for research aims and were 20-year grafted on sour orange rootstocks. For selection of trees, the same height, crown, and other morphological attributes were considered. As the fruit quality may be differ in different parts of crown, fruits were harvested from different geographical orientations of crown. Samples were gathered after full bloom at the 30-day intervals. The measured parameters were included fruit weight, diameter, peel thickness, dry matter and hesperidin flavonoid in extraction of various fruit tissues. Extraction was conducted by methanol and hesperidin content recorded by High Performance Liquid Choromatography (HPLC). Chemicals and reagents used in this study were high quality grade and acquired from Sigma-Aldrich
Results and Discussion: Results showed that the fruit harvesting time significantly affected on fruit diameter, peel thickness, dry matter and also hesperidin content of tissue extraction. Fruit diameter variation was related to the fruit weight. The highest fruit weight attained in cultivars Lisbon and Eureka (88.39 g and 84.72 g, respectively) at the fourth harvesting time (135 days after full bloom) and the minimum, in sour lemon cv. Cluster (4.16 g) at the first harvesting time (45 days after full bloom). The maximum of fruit diameter was recorded in cultivar Lisbon (54.81 mm) at the fourth harvesting time and the minimum diameter in cultivar Eureka (20.75 mm) at the first harvesting time. Fruit peel thickness at the first harvesting stage increased and then decreased. Cluster sour lemon cultivar possessed the highest peel thickness (7.16 mm) and the Eureka cultivar had the minimum (4.66 mm). Percentage of dry matter increased at the first harvesting stage and then decreased. The maximum percentage of dry matter was recorded in cluster sour lemon cultivar (22.83%) and minimum in Lisbon lemon cultivar (11.36%). The highest amount of hesperidin was observed in Lisbon cultivar (1606.93 ppm). These amounts decreased afterward until fruit harvesting time. The highest hesperidin content was produced in albedo tissue. Lisbon lemon in the hesperidin was better than the other two cultivars. It is concluded that the most suitable time of mature fruits harvesting is 45 days after full bloom. At this time the fruit diameter of lemon cv. Eureka, Lisbon and Cluster were 20.7, 22.8 and 25.8 mm; respectively. Hesperidin flavonoid was produced in albedo tissue in all cultivars. Therefor; fruit albedo tissue can be regarded as the best tissue for extracting hesperidin. Hesperidin was severely affected by harvesting time, tissue and cultivar. Hesperidin was achieved in the most amounts at the first harvesting stage in Lisbon lemon compared to all studied cultivars. As the fresh consumption of Eureka, Lisbon and specially Cluster lemon is few, thus preparing programs to extract flavonoid and use this cultivar in food industries is suggested.
Research Article
Seyyedeh Mahdiyeh Kharrazi; Ali Tehranifar; Seyyed Hossein Nemati; Abdolreza Bagheri
Abstract
Introduction: Amaryllis is grown as pot outdoor plant and cut flower. Generally, this ornamental plant propagates by seed, suckers and scale cutting. Propagating by seed is not commercial and often used to produce new varieties. On the other hand, number of bulblets per mother bulb is very low under ...
Read More
Introduction: Amaryllis is grown as pot outdoor plant and cut flower. Generally, this ornamental plant propagates by seed, suckers and scale cutting. Propagating by seed is not commercial and often used to produce new varieties. On the other hand, number of bulblets per mother bulb is very low under normal condition. Besides each bulb produces only 2 or 3 bulblets in a growing season and they become mature and produce flower stalk after 2 to 3 years. In some cases bulbs have no capacity to produce bulblet. Therefore, one of the strategies for shortening the growth period of the plant is to improve the traditional methods of plant propagations.
Materials and Methods: This study was done as a factorial experiment in a completely randomized design with 7 replications to evaluate the effects of medium and position of twin scales in mother bulbs on propagation of bulblets, in order to increase the rate of propagation of this ornamental plant. To measure wet and dry weight of explants, 3 replicates were used. For propagation, bulbs were cut radially into 12 equal pieces, so that each pieces were contained a part of the basal plate. To evaluate the effects of position of twin scales in mother bulbs, pieces were divided as twin scales and classified in 5 groups, so that the outermost twin scales was grouped in class 1 and the innermost twin scales was grouped in class 5. After that, the scale cuttings were dipped in 0.1 % carbendazim solution for 25 minutes and then surface water were dried using sterilized tissue paper. Media that used in this study were sand, perlite, vermiculite, Peat moss and cocopeat. For removing possible contamination from the media, all media were autoclaved for 30 minutes at 121 °C. Then twin scales cuttings were cultured in vented transparent plastic containers that filled with different media and were kept in a growth chamber at 25 °C and 16 hours lighting.Number of produced bulblet, bulblet diameter, root number, root length, fresh and dry weight of plants and browning rate of scales were recorded at the end of the experiment.
Results and Discussion: The results showed that medium and twin scale position in the mother bulb had a significant effect on the quality produced bulblet. The highest fresh weight of bulblet (1.58 g), bulblet dry weight (0.21 g) and the maximum diameter of the produced bulblet (1.5 cm) were obtained in the outermost twin scales and peat moss medium. Analysis of variance showed that the effect of culture medium on the number and length of produced leaf was significant (p
Research Article
Peyman Jafari; Amirhooshang Jalali
Abstract
Introduction: Spinach is one of the most important leafy vegetables, rich in calcium, phosphorus, potassium, vitamin C and B-carotene, and it is likely to be Iran's origin. More than 30 percent of the area under cultivation of in Iran leafy vegetables, allocated to spinach plant. Spinach is a cool season ...
Read More
Introduction: Spinach is one of the most important leafy vegetables, rich in calcium, phosphorus, potassium, vitamin C and B-carotene, and it is likely to be Iran's origin. More than 30 percent of the area under cultivation of in Iran leafy vegetables, allocated to spinach plant. Spinach is a cool season crop and its cultivation is done in the fall and in early spring. Various regions of Iran, has the vast genetic diversity in relation to the mass of spinach. In a study to evaluate the yield and agronomic traits spinach 121 mass Iran, the masses were divided into six clusters that each cluster has specific morphological and agronomic traits. Leafy vegetables, especially spinach are the main sources of nitrate absorption and about 70 percent of total dietary nitrate intake per person per day is provided by leafy vegetables.
Material and Methods: To study the preliminary agronomic and morphological traits and nitrate amounts of 100 Iranian spinach mass are available in GenBank, an investigation was carried out in Agriculture and Education Center Research in Esfahan for two years (2013-2014) by using of five mass dominant cultivars, and two control landrace (Varamin 88 and Varamin prickly seed). The aim of the first year of the study was the primary isolation of superior landraces based on agronomic traits of spinach. At the end of the first year of growth, seed traits, including the type (smooth-prick), the width of the blade, leaf color, wrinkling of leaf area, leaf thickness, the petiole (standing, half-standing and sleeping), petiole length, shape of leaf, the shape of the leaf tip, bolting during plant growth and the number of male and female were determined. A total of 25 landraces selected in the first year of study were compared in the second year using a randomized complete block design with three replications. Studied traits were: yield, dry matter yield, number of leaves, leaf length, leaf width, and petiole length and nitrate levels. Statistical analyses of the data, correlated traits were performed using SAS software and comparisons of means calculated by using LSD at 5%.
Result and Discussion: The results showed that 21.5% of the populations used in this study had the petiole with a standing (vertical) position and 25.2% of them had a long petiole. Length of the petiole and hoisted were considered desirable trait for mechanized harvesting. However, varieties have high nitrate concentrations, or in cases where the management of nitrogen fertilizers does not do well, longer tail leaves are an undesirable trait because the accumulation of nitrate in the tail leaves is more than leaf spinach. 35.5% of spinach leaves landrace used in this study were green color. Leaf color in leafy vegetables is very important. Leaf length, have a range of 11 cm in the Kashan, up to 18 cm in mass TN-69-101 (collected from Lorestan). In this study the agronomic characteristics of the mass of the spinach, length of leaf blade mass in Kashan, Shahreza and Najaf Abad, were 15.50, 11.50, and 9.50 cm, respectively, and all three populations were significantly different in this respect. A significant positive correlation was observed between leaf length and leaf width (0.78**). The highest of fresh yield was 32.59 t ha-1 and produced by Varamin 88 that with six masses (TN-69-73, Varamin- prickly, TN-69-74, TN-69-153, TN-69-140, TN-69-58) did not differ statistically. Three populations of TN-69-153, TN-69-140 and Varamin- prickly (advanced masses prickly Varamin) both in terms of fresh and dry matter yield were superior. The (TN-69-78) mass with 17 leaves, the highest, and (TN-69-22) mass with 11/33 leaves, the lowest number of leaves produced among the different masses. Leaf blade width in the mass TN-69-31, was equal to 12/38 cm and with the eleven other populations had a significantly blade width more than other the masses. In terms of nitrate in shoots, TN-69-153 population with 1708 mg of nitrate per kg of dry matter had the highest amount of nitrate.
Conclusion: The results of this study showed that considering the diversity traits among different populations of spinach in various parts of the Iran can be provide suitable potential for agronomic and breeding purposes. The masses after selection and purification can be available to farmers and producers.
Research Article
Naser Nasrolahzadehasl; Mojtaba Delshad; Abdolkarim Kashi
Abstract
Introduction: Cucumis sativus L. is one of the most eminent and consuming vegetables which is widely cultivated in the Middle East. Using the controlled and greenhouse cultivation is one of the most appropriate methods to increase production per unit area. In this method, controlling the effective factors ...
Read More
Introduction: Cucumis sativus L. is one of the most eminent and consuming vegetables which is widely cultivated in the Middle East. Using the controlled and greenhouse cultivation is one of the most appropriate methods to increase production per unit area. In this method, controlling the effective factors of production such as plant nutrition is the important factor to achieve high performance. Besides the accuracy applied in nutritional regulation of plant roots (both in soil and hypothermic environments), in many cases, foliar nutrition is considered by breeder of greenhouse productions. Foliar nutrition is more effective on young leaves, and deficiency of macro and micro nutrients can be removed by this factor. Khassib is one of the most important cultivar of greenhouse cucumber which is widely cultivated in Iran. The present study was conducted to evaluate the effect of foliar application on greenhouse cucumber.
Materials and Methods: The experiment was performed on greenhouse cucumber (cv. Khassib) for five months (from March 2007 to July 2008) in Ziba Dasht Technical Instruction Center which is located near Karaj, Iran. For this reason the experiment was conducted based on split-split-plot design with three replications. Eight experimental treatments were applied for foliar application including U1C1B1: urea + calcium nitrate +boric acid, U1C1B0: urea + calcium nitrate, U1C0B1: urea + boric acid, U1C0B0: urea, U0C1B1: calcium nitrate + boric acid, U0C1B0: calcium nitrate, U0C0B1: boric acid, U0C0B0: control. The effects of urea, calcium nitrate and boric acid in concentrations 3, 10 and 0.5 (gL-1) respectively on qualitative and quantitative characteristics of greenhouse cucumber, including fruit yield, yield of first class fruit, number of fruits, percentage of first class fruit, fruits T.S.S, plant length, percentage of leaf dry matter, and leaf weight ratio were studied.
Results and Discussion: The results showed that calcium nitrate had a significant effect on fruit yield at 5% probability level. Foliar application of calcium nitrate with concentration of 10 gL-1resulted in an increase of yield so that the average of fruit yield for sprayed plants was 3917.9 g per plant, while this value in control plants was 3576.5 g. Boric acid with concentration of 0.5 gL-1 had a remarkable effect on fruit yield at 5% probability level that enhanced the average of yield from 3591.6 to 3902.8 g per plant. The interaction of U×C×B treatment on fruit yield at 1% probability level was significant, while this value was not found among other treatments. Foliar application with calcium nitrate results in an increase of yield and production in young and growing fruits. The augmentation of yield in treatment U1C0B0 due to the facts that pure urea and calcium nitrate have 46% and 16% nitrogen, respectively, i.e., extra nitrogen causes toxicity and branching instead of fruiting. Among three-way interactions, U×C×B statistically had a remarkable impact on the yield of first class fruit at 1% probability level and also the maximum and minimum of this value belonged to U1C0B0 and control, respectively. Only U×C×B had a remarkable impact on plant length among all interactions. Generally, the growth of cucumber depends on genetic features, temperature and soil productivity. The highest level of leaf area index was for calcium nitrate that indicated the significant effect at 5 % probability level with the mean of 15.89. When we compare the foliar application treatments with fosamko, it can be found that the spraying treatments affected leaf dry matter significantly at 1% and 5% probability levels, while this value was not found for control treatments. However, there was no significant difference between using and not using nutrition compared to fosamko on yield.
Conclusion: According to the findings of the present study the following factors can be concluded: a) Among the main effects, calcium nitrate played the eminent role on most traits, after that boric acid and finally urea carried this role; b) Among two-way interaction, only U1B1, as foliar application, significantly affected the yield of grade 1 fruit; c) Among three-way interactions, only U1C0B0, as foliar application, significantly affected the yield of grade 1 fruit, total fruit and the number of fruit; d) There was no a significant change on qualitative features of cucumber using nutrition compared to fosamko. Therefore, cucumber production can be performed by cheaper methods with no change in qualitative characteristics. Finally, due to the fact that cucumber is one of the most important vegetables in Iran, it is suggested that various studies with different fertilizers will be conducted on cucumber.
Research Article
Mohammad Hossein Sheikh Mohammadi; Nematollah Etemadi; Ali Nikbakht
Abstract
Introduction: Drought is one of the most detrimental abiotic stresses for turfgrass growth across a wide range of geographic locations. Most cool-season grass species are not well adapted to extended periods of drought, particularly during summer months. Decline in turf quality caused by drought stress ...
Read More
Introduction: Drought is one of the most detrimental abiotic stresses for turfgrass growth across a wide range of geographic locations. Most cool-season grass species are not well adapted to extended periods of drought, particularly during summer months. Decline in turf quality caused by drought stress is a major concern in turfgrass culture. Therefore, developing management practices for improving drought resistance of turfgrasses has become essential in arid and semi-arid regions, especially during water use restriction. One strategy to improve plant drought resistance is to promote drought avoidance by reducing water loss during drought, which may be achieved by slowing growth rate of shoots and lowering leaf area canopy to reduce demand for water. Application of growth regulators is one of the methods for increasing resistance of plants to biotic and abiotic stresses. Trinexapac-ethyl (TE) is one of the most widely used PGRs in the management of cool-season and warm-season turfgrass species. TE absorbed quickly by foliage and slow cell elongation through inhibiting of converting one form of gibberellic acid (GA20) to another (GA1). Most studies conducted under non-stressed conditions found that TE application increased chlorophyll content, turf quality, turf density and reduced shoot extension rate. We hypothesized that TE may influence plant tolerance to drought stress. Limited available data─ as reported in the above referred studies─ suggest that TE application may be beneficial for plant tolerance to stresses, but the effectiveness varies with turfgrass species, dose and duration of TE treatment, and type of stress. The main aim of this research is to evaluate the effect of Trinexapac-ethyl on increased resistance to drought stress in wheatgrass.
Materials and Methods: Wheatgrass (Agropyron desertorum L.) was used in this study. This study was conducted in field conditions at Isfahan University of Technology, Isfahan, Iran.. Wheatgrass native seeds (Agropyron desertorum L.), collected from the turfgrass research farm at Fereydan, Isfahan, which were cultivated hand broadcast in plots (3m × 2m) with seeding rates of 30 gm–2. A factorial experiment based on randomized complete block design (RCBD) with three replications was conducted for TE (Primo Maxx; Syngenta Crop Protection, Inc., Greensboro, NC) and drought stress. Treatments involved three levels of Trinexapac-ethyl growth regulator (0, 0.25 and 0.5 kg/h) and two levels of drought stress (with irrigation and without irrigation). After planting, the plots were irrigated to maintain soil moisture at 80% field capacity or higher. Irrigation was applied as required to prevent any drought stress during grass establishment. Turfgrass species were maintained at cutting height of 4 cm and were mowed once a week using a reel-type mower. All data were subjected to analysis of variance using SAS 9.1 (SAS Institute Inc., Cary, NC) and Fisher’s protected LSD test was employed at the 5% probability level..
Results Discussion: Results indicated that Trinexapac-ethyl and drought reduced growth, fresh weight and dried above ground organs significantly. Wheatgrass growth in concentrations 0.25 and 0.5 kg/h were 19.20 and 26.90%, respectively. Previous studies reported plants that have slow-growing shoots may survive more extended periods than faster-growing plants in drought conditions. Slow growth may reduce the adverse impact of drought by conserving water and carbon energy, and plants can use limited water to survive drought for an extended period of time. Unlike drought stress, Trinexapac-ethyl improved the quality of plant tissues and their color. Increase in turf quality under TE treatment might occur as a result of improved canopy photosynthesis capacity and single-leaf photochemical efficiency. Drought stress reduced relative water and chlorophyll content, increased proline level and finally led to electrolyte leakage. Trinexapac-ethyl improved wheatgrass in drought stress conditions by increasing relative water content, prolin, chlorophyll and decreasing electrolyte leakage and increased wheatgrass to drought stress resistance. Proline acts as an osmotic regulator in cytoplasm and vacuoles, protects proteins against dehydration, adjusts osmosis; detoxify radical active oxygen species, keeping more stable antioxidant enzymes. Proline immediate increase under drought stress is associated with decreasing leaf water content, in turn, induced drought tolerance. Under drought stress conditions, penetration of root depth and effective root depth has been increased, while Trinexapac-ethyl did not affect root traits significantly. The results of the present study indicated that TE decreased damages on drought stress probably via improving turf quality, chlorophyll concentration, leaf water content, proline content and less electrolyte leakage in Wheatgrass.
Research Article
Ramin Mahdavi; Madhi Parsa; Ali Gazanchian; Hamidreza Khazaie
Abstract
Introduction: Over the last three decades, turfgrass breeders have put significant effort into breeding and developing turf species that have good drought resistance. As water conservation becomes an important issue, an interest is increasing in identifying grasses that require less water. Lack of water ...
Read More
Introduction: Over the last three decades, turfgrass breeders have put significant effort into breeding and developing turf species that have good drought resistance. As water conservation becomes an important issue, an interest is increasing in identifying grasses that require less water. Lack of water resources is most problems to increasing urban green spaces. Plants with good drought resistance are those that are able to survive stress by means of drought avoidance, drought tolerance at leaf water potentials, or both. The efficient use of water is made possible by understanding the effects of soil moisture water on crop development and yield. Drought affects the visual quality, growth rate and evapotranspiration. Researchers reported that turfgrass subjected to drought conditions for short periods could sustain a fairly good appearance by soil moisture about half of its consumptive use whenever soil moisture level falls to near permanent wilting point. Drought stress caused decrease in RWC and visual quality of many grass cultivars. In drought conditions resistance grass showed increase in proline content on their leaves. Therefore the use of native grasses with high-strength instead of imported grass with low-resistance is one way to increase landscape areas and reduce costs. The purpose of this study was to be compared native grasses with commercial grass cultivar “Super sport”.
Materials and Methods: The objective of this study was to evaluate the effect of soil moisture stress levels included 85% (control), 65% and 45% of field capacity on native species Brumos tomentellus, Festuca rubra and F. arundinacea and commercial cultivars Super sport (control) under greenhouse conditions. Plants were cultured in PVC containers measuring 9 cm in diameter and 60 cm deep. Soil was mixture of 70% loam soil, 20% pit mass and 10% sand. Greenhouse air temperature was maintained between 22 and 28 centigrade degree. All plants were maintained under well watered conditions for 45 day before drought stress. This experiment was conducted as factorial experiment based on completely random design with four replications. Measured parameters were length and width of leaves, chlorophyll a, chlorophyll b and total chlorophyll content, visual quality, electrolyte leakage, RWC and proline content of leaves. Length and width of leaves measured with ruler. Proline content, RWC percent, chlorophyll a, chlorophyll b and total chlorophyll content of leaf, visual quality and leaf electrolyte leakage was measured with standard protocols. Analysis of the data by statistical software JMP 8 and graphs with Excel 2010 was drawn.
Results and Discussion: Result of the experiment showed those native species have different response to soil moisture stress conditions. The highest and lowest length of leaves were observed in 65% field capacity in F. arundinacea and super sport grass, respectively. The results showed that width of leaves of B. tomentellus increased and decreased in super sport. Under soil moisture stress conditions, F. arundinacea has best visual quality with 7.66 score. Highest chlorophyll a and total chlorophyll were observed in tall fescue grass. The lowest electrolyte leakage under drought stress was obtained from F. rubra with 25.66 percent. RWC content in the native F. arundinacea increased to 77.80 compared with super sport (control). B. tomentellus under soil moisture stress showed the highest proline content and commercial cultivar (super sport) indicate lowest proline content at 45% field capacity. Selahvarzi and et al. (2009) found that visual quality of tall fescue decrease in drought stress. In drought stress RWC percent decrease in grass species. Proline content was increased in drought stress at Lolium perene cool season grass. Much studies on native cultivar indicated that native turfgrass cultivar have more resistance to drought stress compared with exotic turfgrass cultivars.
Conclusions: According to the results, we said native grass species under drought stress conditions have better quality compared with imported grass cultivar Super sport. Visual quality in native grass were suitable for use in urban landscape, that visual quality showed little change in soil moisture stress and leaves were fresh in this conditions. Native grass cultivars were more resistance than imported grass cultivar. This study showed that native grass such as F. arundinacea and F. rubra has low cost to use and these turfgrass need to lower water soil moisture than commercial grass Super sport.
