Pomology
Masud Nazeri; Seyyed Jalal Tabatabaie; Yavar Sharafi
Abstract
Introduction
Water scarcity is one of the most important limiting factors threatening the production of horticultural crops. Approximately, 45% of the world's arable land is subject to permanent or intermittent water shortages, and approximately 50% of the world's annual yield is lost due to drought. ...
Read More
Introduction
Water scarcity is one of the most important limiting factors threatening the production of horticultural crops. Approximately, 45% of the world's arable land is subject to permanent or intermittent water shortages, and approximately 50% of the world's annual yield is lost due to drought. Due to climate changes, especially the increase temperature and decrease rainfall in recent years in Iran, most of the gardens are facing limited water resources. In order to reduce water stress, increasing water use efficiency by naval technics seems to be crucial. Peach fruit growth mainly depends on adequate water supply. Therefore, water stress reduces the growth of the fleshy part and the quality of the peach fruits. Split root means placing a part of the root in different conditions compared to the remains of the root. Studies on split root culture were done in the laboratory for the first time. Increasing water holding capacity by split root system may improve soil- plant water availability. Furthermore, many studies indicated that Mycorrhiza and Trichoderma fungi improve the absorption of water and nutrients by plant. Increasing the absorption of water and nutrients leads to increasing growth and yield. The aim of this research was to improve the water efficiency and the use of low-yielding lands by placing a bag containing pumice and inoculating the roots with fungi.
Materials and Methods
This experiment was performed as a factorial experiment based on randomized complete blocks design with three replications for two years. Treatments included placing the bag close to the trunk of peach trees in three levels (without bag, one bag and two bags), different levels of irrigation (50, 75 and 100% of field capacity) and root inoculation treatments with mycorrhiza, Trichoderma fungi and control without fungus. Redtop peaches grafted on GF677 rootstock were planted in May 2018. The bags were placed at a depth of 60 cm and at a distance of 40 and 60 cm from the tree trunk. The bags size was 40 liters filled with pumice. At 20 cm from the top of the bag, three holes were made to remove excess water from that part and as a signal to cause the root to move towards the bag. For plants treated with mycorrhiza, 250 g of Mycorrhiza glomus was mixed and for plants treated with Trichoderma, 4.5 g of Trichoderma harizanium was mixed with pumice in the bag. In treatments with no bag placement, the plant roots were inoculated with fungi. Characteristics such as relative water content (RWC), yield, total soluble solids (TSS), titratable acidity (TA), TSS/TA, total phenol and fruit anthocyanin were measured at the end of growing season. Fruit skin color characteristics including L*, a*, b*, Chroma and Hue were measured with a colorimeter. Statistical analysis was performed by SAS software version 9.1. Mean data were compared using Duncan's multiple range test. drawing diagrams done by Excel software.
Results and Discussion
The results showed that bag placement increased RWC. The highest RWC of leaf was measured in the treatment of placing two bags, 75% irrigation and root inoculation with Trichoderma fungus. In the main effect of bag placement, irrigation levels and root inoculation, the highest RWC of leaf was observed in placing a bag, 100% irrigation and root inoculation with Trichoderma fungus, respectively. The treatment one bag, 100% irrigation and root inoculation with mycorrhiza improved vegetative growth and produced the largest trunk diameter. Yield in terms of fresh weight of fruit in two-bag placement, 100% irrigation and root inoculation with mycorrhiza was increased by 1.8 compared to the control. The highest TA was measured in the treatment of placing a bag, 50% irrigation and root inoculation with mycorrhizal fungus. Treatment without bag placement, 75% irrigation and without fungus inoculation had the highest total soluble solids and TSS/TA of fruit. The index ratio of TSS/TA is used to determine the taste of the fruit. The highest total phenol and anthocyanin of fruit was observed in treatments without bag under 50% irrigation levels. One bag placement, 75% irrigation without fungal inoculation treatment and no bag placement treatment, 50% irrigation, mycorrhiza inoculation caused the a* and L* of the fruit skin increased. The interaction effect of the three factors of bag placement, irrigation levels and root inoculation with fungus had no significant effect on Hue and b*.
Conclusion
The results of this experiment showed that water consumption can be reduced by placing a bag. The finding of the experiment led to the conclusion that a bag placement treatment, 75% irrigation and inoculation with mycorrhizal fungus improve fruit yield and quality of peach trees
.
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.
Hosein Nazari Mamaqani; Seyyed Jalal Tabatabaie
Abstract
Introduction: The N source used in commercial hydroponic culture of vegetables is mainly NO3-N. The rate of NO3- uptake is usually high, particularly in leafy vegetables and it can be markedly increased when the NO3- supply in the environment is high. An abundant N supply leads to a high NO3-N absorption ...
Read More
Introduction: The N source used in commercial hydroponic culture of vegetables is mainly NO3-N. The rate of NO3- uptake is usually high, particularly in leafy vegetables and it can be markedly increased when the NO3- supply in the environment is high. An abundant N supply leads to a high NO3-N absorption and accumulation in plants. When NO3- rich vegetables are consumed, various harmful effects on human health may occur such as met-hemoglobinemia (Blue Baby Syndrome) and cancer. Keeping levels of NO3- below limits of FAO seems to be impossible without changing conventional fertilizer application techniques. The suitability of urea for the cultivation of field crops has been well documented. Urea is used as the main source of N fertilizer for crops grown in soil. Its use as N source for crops grown under the hydroponic system has yet to be evaluated. To hydrolyze urea, the enzyme urease requires Ni as a component. Substitution of urea for commonly used N03-N fertilizers in hydroponic culture of vegetables would not only enable to avoid excessive accumulation of N03- in plants but would also reduce the cost of production. Leafy vegetable crops, such as lettuce and spinach, contain large amounts of N03-N. Therefore, it is important to reduce N03- concentrations in hydroponically grown with lowest negative effects on yield.
Materials and Methods: The experiments were carried outin greenhouse hydroponicsResearchFaculty of Agriculture, University of Tabriz in randomized complete block designwithtwo factors ureaatfivelevels of 0,25, 50, 75and100milligrams perliter(U0, U25,U50, U75, U100)andnickelattwo levels of0and2mg per liter (Ni0, Ni2)ofnickelsulfate(NiSO4)in4replicatesusinglettuce(Lactuca sativa cv. Siyahoo). Plants fed with the modifiedHoagland solutionorhalf theconcentration. Treatments added to nutrient solution when plants were in four leaf stage. Plants were harvested 50 days after treatment. Different organs (leaves, stems and roots) were separated and each separate simultaneous freshweight wasmeasured. Dry weight of organs wasmeasured afterit was oven-dried at 80ºCfor 72h. Leavesoven-dried andthenpowdered, and weredigested(usingacid) tomeasure theelements. Extracts from thedigestionmethodwere used for determination ofnickelusingDimethylglyoximemethod.Spectrophotometer used to cover the wavelength at 530nm. Potassium was measured by Flame Photometer410.Totalnitrogenwas measuredbyKjeldahlmethod.Thehomogeneouspowders of dried leaves with hot water were extractedwithnitratemeter(Horiba, Japan)and they were used to measuretheirnitrate content. Analysis was performed usingthe Software Statistical Package for the Social Science (SPSS) v. 16.0. Individual treatment means were compared with a Duncan’s test to determine whether they were significantly different at the 0.05 probability.
Results and Discussion: U50treatedwith 1.8 fold increasecompared with thecontrol groupshowed thehighestfresh weight. The yield increased with increasing concentration to 50 mg/l urea, butat higher urea concentrations, 50 mg/l,yieldsignificantlydecreased, althoughitwas significantlyhighercompared to control. .Enhanced growth and yield in two levels of U25 and U50were coerced. It was duo tohydrolysis urea with the help nickel stored in seed endosperm and also contamination application of nickel fertilizers in nutrient solutionsthat led to release of urea nitrogen.The highestandthelowest concentration ofnickelinleaveswith11-fold increase,were observedatconcentrations ofU50andU100, respectively. Dilution phenomenon occurred with increasingurea concentrationmore than U50.Nickelconcentration inleaveswassignificantlyincreased that this is theopposite offresh weightanddry weight. In U50 treated K concentration was 1.6-fold higher compared to control. With increasing urea concentration more than U50,K concentration decreased. Applyingthe Ni, 8 percent decreased K concentration in leaf tissues. With increasing urea innutrientsolution, totalnitrogenconcentration of leaf tissuealsoincreased,so that theplantsU100 have 1/1-foldmoretotalnitrogencomparedwithU25plants. Theinteractions betweenthe treated also showed that plantsU0Ni2compared to control(U0Ni0), have 1.2-fold moretotalnitrogen. Concentration ofnitrateinplantsleavesthat showednickelwas 1.2 fold highercompared to the plants withoutnickel.Interactive effectofureaconcentration andapplication ofnickelalso showedthat treated plants hadU0Ni0 2.6-fold more nitratethanU0Ni2plantsleaftissues.
Conclusion: Urea was hydrolyzed in low and middle concentrations (U25 and U50) and led to increasing yield. An inhibition of NO3- uptake can result from the action of Ni on H+- ATPase pump, though it can also affect the carrier of H+/NO3symport. Moreover, proteins of the NO3- uptake system contain -SH groups, and due to that they are sensitive to heavy metals including Ni.
Rozita Khademi Astaneh; Seyyed Jalal Tabatabaie; Sahebali Bolandnazar
Abstract
Selenium is a non metallic chemical element that affects plant growth and development and but it can due to the presence of antioxidant defense system as a matter of basic human and animal health has been identified. An experiment was conducted to study the effect of Se on physiological characteristics ...
Read More
Selenium is a non metallic chemical element that affects plant growth and development and but it can due to the presence of antioxidant defense system as a matter of basic human and animal health has been identified. An experiment was conducted to study the effect of Se on physiological characteristics and yield of Brussels sprouts (Brassica oleracea var. Gemmifera) with six levels of Se (0, 2, 4, 8, 16 and 32 mg/l) from sodium selenate. The experiment was arranged in a completely randomized design with four replications under greenhouse conditions. The results showed that yield in terms of fresh weight of sprout was significantly (P≤0.01) affected by Se concentration so that increasing Se concentration from 0 to 8 mg/l increased the yield and chlorophyll index, electrolyte leakage (EL) in leaves decreased then with increasing Se concentration decreased the yield and EL in young leaves increased. The highest yield was observed at 8 mg/l Se concentration that was 40% higher compared to the control treatment. With increase concentration of Se in the nutrient solution increased Se concentration and as follow old leaves>young leaves> sprouts. The results showed that Se can be added at the 8 mg/l to the nutrient solution for growing Brussels sprout.
Mehdi Oraei; Seyyed Jalal Tabatabaie; Esmaeil Fallahi; Ali Imani
Abstract
Abstract
Salinity tolerance is one of the major factor influencing crop productivity in arid and semi-arid areas. The salinity tolerance of fruit trees can be enhanced through the use of tolerant rootstocks. This experiment was conducted to investigate the effects of salinity stress and rootstock on ...
Read More
Abstract
Salinity tolerance is one of the major factor influencing crop productivity in arid and semi-arid areas. The salinity tolerance of fruit trees can be enhanced through the use of tolerant rootstocks. This experiment was conducted to investigate the effects of salinity stress and rootstock on the growth, photosynthetic rate and nutrient concentrations of almond (Prunus dulcis Miller.) cv. “Ferragnes” grown in the soilless culture and controlled environment. Three levels of NaCl (0, 50, 100 mM) and two rootstock (GF677, Tuono) was factorially combined in a randomized complete block design with four replications. The results showed that the salinity stress had a significant diminish effects on vegetative and physiological characteristics and nutrient concentrations of almond. The severity of the adverse effects of salinity varied among rootstocks. Fresh and dry weights of leaf and root, leaf number and chlorophyll index was increased in F/GF677 at 50 mM salinity level and then decreased compare to that in control, however it was decreased at 100 mM salinity concentration in F/Tuono. Photosynthetic rate, leaf area and K/Na ratio was decreased with increasing salinity in both rootstocks, it became more pronounced in F/Tuono. With increasing NaCl levels, leaf concentrations of N, P, K was decreased and Na concentration was increased in both rootstocks. This results imply that GF677 have a exclusion mechanism such as restrict either the uptake or transport of Na from root to shoot or maintain sufficient level of K, have a higher salt tolerance than Tuono hence, under salinity conditions can be useful salt-tolerant rootstock for different almond cultivars.
Key words: Almond, Rootstock, Salinity tolerance, Salinity stress, Photosynthesis
