Growing vegetables
Mitra Jabbari; Reza Darvishzadeh
Abstract
Introduction
Pepper is a rich source of essential vitamins and minerals. Like tomatoes, pepper plays an important role in preventing heart diseases due to its high amount of antioxidants. Fruit yield is a complex trait that is not only controlled by several genes, but also greatly influenced by the ...
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Introduction
Pepper is a rich source of essential vitamins and minerals. Like tomatoes, pepper plays an important role in preventing heart diseases due to its high amount of antioxidants. Fruit yield is a complex trait that is not only controlled by several genes, but also greatly influenced by the environment. On the other hand, fruit yield is affected by a large number of other traits and their interaction. Therefore, it is very important for plant breeders to know the relationships between these traits and their interaction effects. The path coefficient analysis is a method that clarifies the relationships between traits and their direct and indirect effects on fruit yield. In this method, the correlation coefficient between two attributes is divided into components that measure direct and indirect effects. Considering the limited studies regarding the evaluation of relationships between fruit yield and other traits affecting fruit yield in pepper, this research was conducted with the aim of identifying these important relationships and evaluating their direct and indirect effects in Iranian pepper populations.
Materials and Methods
In order to carry out this research, the seeds of 30 Iranian pepper accessions were collected directly from the farmers. The experiment was conducted in the form of pot cultivation in the research greenhouse of the Faculty of Agriculture of Urmia University in a completely randomized design with five replications during 2015-2016. After the flowering stage, the desired traits were estimated. Variance analysis was estimated, after examining the basic hypotheses of variance analysis by SAS9.4, as well as the genotypic and phenotypic correlation between traits based on the restricted maximum likelihood (REML) procedure in the SAS9.4 software. Step-by-step regression analysis was used to determine the traits with the most variation justified the fruit yield. The Durbin-Watson test was performed to investigate the independence of experimental errors. Analysis of path coefficients was performed based on the results of stepwise regression and genotypic correlation of traits in the R V.4.0.5.
Results and Discussion
In order to understand the relationships between traits and use them in breeding programs, the phenotypic correlation was estimated. In this study based on the results of phenotypic correlation, leaf width and leaf length (0.651), single fruit weight and fruit circumference (0.784), fruit circumference and fruit diameter (0.625) and pulp weight and fruit diameter (0.610), showed positive and significant correlation. The purpose of estimating genotypic correlation coefficient is to determine relationships in conditions which in environmental factors are not involved. In the investigation of genotypic correlation, a positive, strong and significant relationship between fruit yield and pulp weight (0.907), fruit circumference (0.891), fruit diameter (0.697), single fruit weight (0.646) and around the plant (0.381) were observed. Given that most of these traits are factors contributing to fruit yield, the presence of such positive and significant genotypic correlation coefficients is reasonable. It can be inferred that pepper accessions with higher fruit characteristics, encompassing factors such as plant density and branching, are likely to exhibit higher fruit yields as well. It's important to note that correlation coefficients are mathematical tools used to measure the linear relationship between two variables. Their significance lies in their mathematical interpretation, and as such, they alone do not provide sufficient proof of a cause-and-effect relationship. Utilizing the results of stepwise regression, less impactful traits or those with minimal effects were eliminated from the model. As a result, seven key traits were identified as the most influential factors affecting fruit yield: pulp weight, plant density, fruit diameter, fruit count, plant height, total seed weight, and branch count.The first characteristic was pulp weight, which was included in the model and explained 78.8% of the fruit yield changes between genotypes. The second characteristic (around the plant) along with pulp weight explained 80.9% of the fruit yield variations. Fruit diameter, together with the previous two characteristics, explained 81.5% of fruit yield variations. In total, the traits included in the model for fruit yield justified 84.6% of the total changes in fruit yield in 30 pepper accessions. In order to better understanding and more accurately interpret of the results, as well as to know the direct and indirect effects and the effect of the traits that were entered into the model through stepwise regression, the path coefficient analysis method was used in this research. Fruit diameter (0.709) and pulp weight (0.289) respectively showed the most positive and direct effect on fruit yield. Fruit pulp weight through fruit diameter had the most positive indirect effect (0.595) on fruit yield. Around the plant showed an indirect positive effect on fruit yield through pulp weight (0.157), fruit diameter (0.392) and number of branches (0.080).
Conclusion
In the present study, the trait of fruit diameter had a positive, strong and significant genotypic correlation (0.697) with fruit yield, and it also showed a positive direct effect (0.709) on fruit yield, these two coefficients can be considered equal, Approximately. Therefore, direct selection based on fruit diameter proves to be a valuable strategy for enhancing fruit yield. The magnitude of residual effects serves as an indicator of the model's accuracy in path analysis. When this value is substantial, it may be advisable to incorporate additional causal variables into the model. In the current study, the residual effects value (0.213) affirms the model's optimal accuracy.This research highlights the effectiveness of employing stepwise multivariate regression and path coefficient analysis to gain a deeper understanding of the fundamental relationships between traits. It underscores that relying solely on correlation relationships is insufficient for comprehensively justifying the associations between these traits.
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 ...
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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.
Ahmad Hajiali; Bahman Zahedi; Reza Darvish Zadeh; Jahangr Kohpalekani Abbasi
Abstract
Introduction: Watermelon (CitrulluslanatusThunb)belongs to Cucurbita genus and Cucurbitaceaefamily. Some people know Watermelon native to India and othersthought of it as native to African countries. The greatest diversity can be seen in West Africa, China and parts of India. Near East and Mediterranean ...
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Introduction: Watermelon (CitrulluslanatusThunb)belongs to Cucurbita genus and Cucurbitaceaefamily. Some people know Watermelon native to India and othersthought of it as native to African countries. The greatest diversity can be seen in West Africa, China and parts of India. Near East and Mediterranean countries are also good places to find relatives and ancestors of watermelon. Like all Cucurbita genuscrops,, Watermelon has a variety of flowers including base, male and female separately located on one slip. In terms of production atglobal level, China is located in the first place followed by America, Iran and the Republic of Korea, respectively.
Materials and Methods: In order to evaluate genetic diversity among Iranian watermelon landraces by morphological traits, 16 landraces alongwith two commercial watermelon cultivars were planted in completely randomized block design with three replications inAgricultural Research Center of Urmia in 2013.
Morphological markers can be an effective means to determine genetic relationsamong cultivars and among selections used in watermelon breeding programs. 18 traits including cotyledon length, fruit length, fruit weight, fruit mass, fruit skin, rind thickness, flesh thickness, yield, seed length, seed width, weight of 100 seeds, vitamin C, pH, TSS, EC, chlorophyll content and plant length were assessed in the studied genotypes. During the fruit ripening,four fruits were selected randomly from each plot and according to the International Institute germplasms (IBPGR / IBGRI),solidscontent (TSS)was measured by using refractometer, pH by using pH meter, and fruit and seed weight by using digital scale. The amount of vitamin C (milligram per 100 grams) was measured using iodometry.
Results and Discussion: Results of variance analysis showed that there were significant differencesamong watermelon cultivars in terms of cotyledon length, fruit length, fruit weight, flesh weight, yield, seed length, seed width, seed weight, vitamin C, soluble solids and EC at the 1% level, while the level of significance with respect toskin weight, chlorophyll content and photosynthetic rate was5%.The results also showed that there were not significant differences among the cultivars in terms of pH, skin and flesh thickness, and plant length, suggesting that there is no diversity among the masses. Based on the means comparisontable,the highestfruit length (39 cm), fruit weight (8.03 kg), fleshweight(4.3 kg), skin weight (3.36 kg) and performance rate (24926 kg in hectare) were observed in Charleston Gray.Isfahan 808 mass showed the minimum fruit length (23.66 cm);Khorasan 806 mass had the least fruit weight (3.33 kg) andskin weight (1.8 kg); and East Azerbaijan 800 and Hamedan 817masses showed the lowest fruit flesh weight (1.5 kg) and performance (13444 kg per hectare), respectively.The highest positive phenotypic correlation (0.968) was observed between fruit mass and fruit weight,whilethe highest negative correlation (-0.815) existedbetween TSS and seed length. The highest positive (0.987) and negative (-0.990) genetic correlation was foundbetween fruit weight and fruit length, and between flesh thickness and photosynthesis, respectively. The greatestheritability was related to 100-seed weight, whereas minimum heritability was due to ph. The studied accessions were classified into three different groupsby using Cluster analysis based on Ward method. Based on the intervaltable,the highest space rate was observed between groups one and three (8.985).The resultsalso showed that the maximum expected heterosis obtained in crosses between genotypes one and three.
Conclusion: Based on the results of this research, improved varieties (Charleston Gray and Crimson Sweet) had the highest level of performance, TSS, fruit weight and flesh weight compared to the native masses.
Alireza Pirzad; Reza Darvishzadeh; Abbas Hassani
Abstract
Introduction: Cumin, sometimes spelled cummin (Cuminum cyminum L.; Apiaceae), also known as Zeera is native from the East Mediterranean to India. Its seeds are used in the cuisines of many different cultures, and it is also used as a medicinal plant, serving as a digestant, as well as being used to treat ...
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Introduction: Cumin, sometimes spelled cummin (Cuminum cyminum L.; Apiaceae), also known as Zeera is native from the East Mediterranean to India. Its seeds are used in the cuisines of many different cultures, and it is also used as a medicinal plant, serving as a digestant, as well as being used to treat anemia and the common cold. Cumin is a drought tolerant plant, has a short growth season of 100 – 120 days, with optimum growth temperature ranges between 25°C and 30 °C. Drought is one of the most important environmental factors that influences seed yield of crop plants in arid and semi-arid regions,through physiological response of plant. To reduce drought stress damages, some synthetic materials like hydroplus superabsorbent polymers, highly hydrophilic due to low cross-links in their structure, can be used to save soil moisture. Thus, superabsorbent polymer may have great potential in restoration and reclamation of soil and storing water available for plant growth and production.
Materials and Methods: To evaluate accumulation of photosynthetic pigments and seed yield of cumin, a factorial experiment was conducted based on randomized complete blocks design with three replications at the Research Farm of Urmia University (latitude 37.53° N, 45.08° E, and 1320 m above sea level).- The soil texture of experimental site was clay loam (28% silt, 32% clay, 40% sand) with 22.5% field capacity, 1.54 g/cm3 soil density, and pH 7.6. Treatments were four irrigation regimes (irrigation after 50, 100, 150 and 200 mm of evaporation from class A pan) and different amounts of superabsorbent polymer (0, 60, 120, 180, 240 and 300 kg/ha). To measure the chlorophyll content (Chlorophyll a, b, and total chlorophyll), 0.25 g of grounded leaves were adjusted to 25 ml by distilled water, and 0.5 ml of this solute was mixed with 4.5 ml acetone 80%. The upper zone of centrifuged solution was taken for spectrophotometery at 645nm and 663 nm wavelengths. To measure the yield of cumin seeds, 2 m2 of each plot was harvested and immediately were dried in the shade and at a temperature of 25 ° C. Essential oil, 25 g of powdered seeds in a one-liter flask, was extracted (W/W) by the Clevenger method (Hydro distillation) for 3 hours.
Results and Discussion: Analysis of variance showed the significant interaction between the superabsorbent polymer and irrigation on the amount of leaf chlorophyll a, chlorophyll b, total chlorophyll, seed yield, percentage and yield of essential oil. This implies a different physiological response of cumin plant in terms of adding different amounts of superabsorbent and irrigation. Means comparison indicated that the highest concentration of chlorophyll a (0.266 mg/l) and total chlorophyll (0.518 mg/l) were obtained from plants irrigated after 50 mm of evaporation without polymer application. The maximum (0.259 mg/l) and minimum (0.028 mg/l) leaf chlorophyll b belonged to irrigation after 200 mm of evaporation using 60 and 240 kg/ha polymer, respectively. The highest yield of seed (1226 kg/ha) and essential oil (36.5 kg/ha) were obtained from well-watered plants (irrigation after 50 mm of evaporation) and 60 kg/ha of polymer. Increasing irrigation intervals from 50 to 200 (50, 100, 150 and 200) mm of evaporation, need 120, 180 and 120 kg/ha polymer correspondingly for production of optimal yield of cumin. Essential oil of cumin plants was gradually and significantly enhanced by increasing irrigation distance, up to 150 mm of evaporation from pan, (with this particle)follow down by severe stress. Like seed yield the lowest yield of essential oil (0.9 kg/ha) belonged to plants irrigated after 50 mm of evaporation using 120 kg/ha superabsorbent (less than irrigation after 200 mm of evaporation). In general, in the case of well-watered plants, irrigation after 50 mm of evaporation with a small amount of superabsorbent (60 kg/ha) produced maximum seed yield and oil. However, if there is no access to water and increasing irrigation intervals twice (irrigation after 100 mm of evaporation from pan) for maximum performance requires the use of 120 kg/ha polymersince the essential oil of irrigation after 200 mm of evaporation is very low. But, if we use higher amounts of superabsorbent (300 kg/ha) more than double the yield of essential oil was obtained from this irrigation level.
Conclusion: A significant interaction between irrigation and superabsorbent, recommended a certain amount of polymer used as the optimum level for each irrigation regime so that the proper yield of essential oil was affected by optimal superabsorbent quantities of chlorophyll, seed yield and essential oil content. In conclusion, the suitable amounts of superabsorbent polymer were different for each irrigation regime,thereforeit is recommendedless than 120 kg/ha for control (non-stress condition) and moderate drought stress- and - 300 kg/ha for severe stress to produce essential oil of cumin plants, respectively.
Shirin Nateghi; Alireza Pirzad; Reza Darvishzadeh
Abstract
The higher levels of essential elements in soil may be caused in optimum yields and crop quality. So it seems to be necessary to examine different levels of nutrients like Fe and Zn on plants and their productivity. To evaluate effects of iron and zinc application on yield and yield components of Pimpinella ...
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The higher levels of essential elements in soil may be caused in optimum yields and crop quality. So it seems to be necessary to examine different levels of nutrients like Fe and Zn on plants and their productivity. To evaluate effects of iron and zinc application on yield and yield components of Pimpinella anisum an experiment was conducted at the research farm of Urmia University in 2009. Treatments, iron application (0, 0.2, 0.4 and 0.6%) and zinc (0, 0.2, 0.4 and 0.6%), were arranged as factorial based on randomized complete block design with 3 replications. Results showed the significant effect of interaction between iron and zinc on the number of seed in per plant,1000 seed weight, biomass yield, seed yield and harvest index (HI). The maximum value of the 1000 seed weight (2.22 g) was obtained from 0% of Fe and 0.2% of Zn, whereas the minimum value of the 1000 seed weight (1.92 g) belonged to 2% of iron and 0% of zinc. The highest number of seed per plant (762), maximum value of biomass yield (2652 kg/ha) and highest of seed yield (1372 kg/ha) were obtained from 0.6 and 0.4 percent of Fe and Zn and the lowest number of seed per plant (272), maximum value of biomass yield (716 kg/ha) and highest of seed yield (470 kg/ha) were obtained from 0 and 0.6 percent of Fe and Zn, respectively. The highest HI (66.18) was obtained at control treatment and the lowest one (46.67) at both 0.4 percent of Fe and Zn. The essential oil percent increase in average values of Fe and Zn spraying. But accumulation of Fe and Zn were the maximum in higher levels of spraying.
