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IntroductionDrought is one of the major limitation on food production worldwide (Hu et al., 2020), which is a growing problem caused by an increasing world population. In wheat cultivation in the Mediterranean climate, mainly the stages of flowering and grain filling are exposed with drought stress. Drought stress reduces the yield of wheat in all growth stages, but its negative effect on grain yield is very severe in the stages of flowering and grain filling. Terminal drought and moisture stress are the main factors of wheat yield reduction under rainfed condition compared to irrigation conditions in Iran. Therefore, one solution to increase the yield is the breeding under drought stress conditions. Due to the low heritability of yield and the complex mechanisms of drought tolerance, little progress has been made in wheat grain yield under drought conditions. Therefore, the grain yield of wheat should be improved indirectly through improving the traits that greatly affect grain yield. Therefore, it seems necessary to identify the quantity and quality of relationships between different traits and grain yield under rainfed conditions. The use of multivariate statistical methods such as path analysis and canonical correlation analysis can help to identify important and effective traits in determining seed yield. This research was carried out with the aim of finding effective agronomical traits on yield and investigating the relationship between these traits and physiological traits under rainfed conditions.Materials and methodsIn order to determine the effective trait on wheat grain yield under rainfed conditions and investigate the relationship between agronomic and physiological traits, an experiment was conducted with 21 lines along with Baran, Hashtroud and Sardari cultivars as control in the form of a randomized complete blocks design in four replications during two years at Khodabande Rainfed Research Station. Plant height (PLH), Day to Heading (DHE), Day to physiological maturity (DMA) at the same time as peduncle yellowing, 1000 grain weight and yield after physiological maturity were measured. To determine the variability between the studied genotypes, descriptive parameters and compound variance analysis were performed based on the expected of mean square, the effects of year and replication was randomly considered and the effect of genotype as a fixed effect using SAS (9.4) software. Simple correlation analysis, path analysis and canonical correlation analysis were used to determine the relationship between traits and to determine effective traits.Results and discussionANOVA showed significant difference between genotypes in terms of all studied traits. Simple correlation analysis showed 19 significant correlation and other correlation were not significant. There is a positive and significant correlation between grain yield and Photosynthesis rate, height and 1000-grain weight, but the relationship between day to heading and grain yield was negative and significant. Path analysis revealed that day-to-heading and day-to-maturity traits with -1.05 and 0.84 had the most direct and negative direct effects on grain yield, respectively. Canonical correlation analysis also showed a significant canonical correlation (r = 0.74) between the set of physiological traits and agronomic traits. According to the results of this study, it was found that agronomic traits of day to heading, day to maturity and height are effective in determining grain yield under dryland conditions.ConclusionThe investigation of the relationship between traits also showed that selection for physiological traits such as transpiration rate and lower stomatal conductance led to selection of genotypes with high height, low day to heading and shorter growth period and finally higher yield under rainfed conditions.Therefore, genotypes with shorter growth periods that can escape terminal-season stresses and lose less water by closing stomata are suitable for high yields under rainfed conditions.

Extended Abstract Background: As one of the most important cereals, bread wheat is an essential part of food security in the world, which supplies one-fifth of the total calories of the world population. Nowadays, the yield of wheat has been affected by climate change-driven drought as one of the most important abiotic stresses that has become an important threat to food security in the world. Root and stomatal traits are especially important in breeding plants to withstand drought stress. Stomata play a key role in controlling carbon dioxide uptake and water loss through transpiration. Therefore, stomatal characteristics are used as indicators of water status and plant growth, especially in drought stress conditions. Having a wide range of physiological and morphological characteristics, roots play an essential role in absorbing water and nutrients. They are also the first organ that sends signals to control the stomata in response to dryness. Therefore, the difference in the structure of the root system can cause the difference between the performance in different cultivars. This study was conducted to investigate stomatal characteristics and their relationship with the root system and plant performance in 24 bread wheat lines and cultivars. Methods: To investigate the relationship between stomatal dimensions and density with the root system, an experiment was conducted on 24 bread wheat genotypes in the form of a randomized complete block design with three replications in the rainfed conditions of the research farm at Zanjan University Faculty of Agriculture in the crop year 2018-2019. In this experiment, PVC pipes were used to study the root system. Twelve seeds were planted in each tube, which were thinned to seven after germination. In each experimental unit, there were two tubes for each genotype, one of which was used to evaluate traits and final yield, and the second tube was used for root studies. Stomatal traits, including the length and width of stomata and number of stomata per unit area, root traits including root length, root diameter, root volume, root surface, and root biomass, and seed yield were measured in the end. The resulting data from the measured traits were analyzed in the form of a randomized complete block design, and the averages were compared using the LSD method. The data were analyzed using multivariate statistical analyses, including regression analysis, path analysis, and factor analysis, and cluster analysis was used to group genotypes. Statistical calculations were done using SAS 9.0 and SPSS 21 software. Results: The results of analysis of variance and mean comparison showed high variability among genotypes for all measured traits. The results of the mean comparison of genotypes showed that genotypes 2, 5, 8, and 16 had the highest yield, and genotype 23 had the lowest yield among the examined genotypes. The highest number of stomata on the upper and lower leaf surfaces belonged to genotypes 5 and 2. In terms of root traits, the highest diameter, volume, length, root surface, and root dry weight at a depth of 0-25 cm were recorded for genotypes 2, 3, 18, and 5, respectively. There was a high and significant correlation between the yield and the number of stomata on the upper and lower leaf surfaces, the length and width of the stomata on the upper leaf surface, diameter, volume, dry weight, and root surface at a depth of 0-25 cm in the soil. Based on the results of stepwise regression analysis, two variables, the number of stomata on the lower leaf surface and root dry weight at a depth of more than 25 cm explained 91.4% of the changes in grain yield. According to the results of the causality analysis of the number of stomata on the lower leaf surface, the most direct effect had a positive effect on seed yield. The results of factor analysis grouped the studied traits into three factors with 82.48% variability justification. The shares of the first, second, and third factors to explaining data changes were 48.86%, 24.62%, and 8.99%, respectively. Based on the plot obtained from factor analysis, genotypes 2, 5, 8, and 16 had high values for the first and second factors. According to the coefficients of the factors, it can be claimed that the genotypes located in this area have high performance, a high number of stomata, and strong root traits, which were found at the soil depth of 0-25 cm. For this reason, these are the genotypes that could produce high yields by absorbing water from the surface layers of the soil by having a large number of stomata and carrying out more photosynthesis. Moreover, the investigated genotypes were divided into three groups from cluster analysis by the ward method and Euclidean distance. Genotypes 2, 5, 8, and 16 were placed in the first group and had the highest mean values for grain yield traits, number and width of stomata on the upper and lower leaf surfaces, and root traits including diameter, volume, and dry weight at a soil depth of 0-25 cm, and root diameter at a depth greater than 25 cm. The lowest values for stomatal length were observed in both leaf surfaces. These were the best genotypes for cultivation in dry conditions. Conclusion: A strong superficial root system can provide the plant with water from scattered rains that occur with low frequency at the end of the growth period. On the other hand, the increase in the number of stomata along with their smaller size reduces leaf pores and enables a faster response of the stomata, and the rapid response of the stomata maximizes water use efficiency. Therefore, having a strong superficial root system along with high stomatal density can increase seed yield in dry conditions.

Background: As one of the most important cereals, bread wheat is an essential part of food security in the world, which supplies one -fifth of the total calories of the world population. Nowadays, the yield of wheat has been affected by climate change -driven drought as one of the most important abiotic stresses that has become an important threat to food security in the world. Root and stomatal traits are especially important in breeding plants to withstand drought stress. Stomata play a key role in controlling carbon dioxide uptake and water loss through transpiration. Therefore, stomatal characteristics are used as indicators of water status and plant growth, especially in drought stress conditions. Having a wide range of physiological and morphological characteristics, roots play an essential role in absorbing water and nutrients. They are also the first organ that sends signals to control the stomata in response to dryness. Therefore, the difference in the structure of the root system can cause the difference between the performance in different cultivars. This study was conducted to investigate stomatal characteristics and their relationship with the root system and plant performance in 24 bread wheat lines and cultivars. Methods: To investigate the relationship between stomatal dimensions and density with the root system, an experiment was conducted on 24 bread wheat genotypes in the form of a randomized complete block design with three replications in the rainfed conditions of the research farm at Zanjan University Faculty of Agriculture in the crop year 2018 -2019. In this experiment, PVC pipes were used to study the root system. Twelve seeds were planted in each tube, which were thinned to seven after germination. In each experimental unit, there were two tubes for each genotype, one of which was used to evaluate traits and final yield, and the second tube was used for root studies. Stomatal traits, including the length and width of stomata and number of stomata per unit area, root traits including root length, root diameter, root volume, root surface, and root biomass, and seed yield were measured in the end. The resulting data from the measured traits were analyzed in the form of a randomized complete block design, and the averages were compared using the LSD method. The data were analyzed using multivariate statistical analy ses, including regression analysis, path analysis, and factor analysis, and cluster analysis was used to group genotypes. Statistical calculations were done using SAS 9.0 and SPSS 21 software. Results: The results of analysis of variance and mean comparison showed high variability among genotypes for all measured traits. The results of the mean comparison of genotypes showed that genotypes 2, 5, 8, and 16 had the highest yield, and genotype 23 had the lowest yield among the examined genotypes. The highest number of stomata on the upper and lower leaf surface s belonged to genotypes 5 and 2. In terms of root traits, the highest diameter, volume, length, root surface, and root dry weight at a depth of 0 -25 cm were recorded for genotypes 2, 3, 18, and 5, respectively. There was a high and significant correlation between the yield and the number of stomata on the upper and lower leaf surface s, the length and width of the stomata on the upper leaf surface, diameter, volume, dry weight, and root surface at a depth of 0 -25 cm in the soil. Based on the results of stepwise regression analysis, two variables, the number of stomata on the lower leaf surface and root dry weight at a depth of more than 25 cm explained 91.4% of the changes in grain yield. According to the results of the causality analysis of the number of stomata on the lower leaf surface, the most direct effect had a positive effect on seed yield. The results of factor analysis grouped the studied traits into three factors with 82.48% variability justification. The share s of the first, second, and third facto r s to explaining data changes were 48.86%, 24.62%, and 8.99%, respectively. Based on the plot obtained from factor analysis, genotypes 2, 5, 8, and 16 had high values for the first and second factors. According to the coefficients of the factors, it can be claimed that the genotypes located in this area have high performance, a high number of stomata, and strong root traits, which were found at the soil depth of 0 -25 cm. For this reason, these are the genotypes that could produce high yields by absorbing water from the surface layers of the soil by having a large number of stomata and carrying out more photosynthesis. Moreover, the investigated genotypes were divided into three groups from cluster analysis by the ward method and Euclidean distance. Genotypes 2, 5, 8, and 16 were placed in the first group and had the highest mean values for grain yield traits, number and width of stomata on the upper and lower leaf surfaces, and root traits including diameter, volume, and dry weight at a soil depth of 0 - 2 5 cm, and root diameter at a depth greater than 25 cm. The lowest values for stomatal length were observed in both leaf surfaces. These were the best genotypes for cultivation in dry conditions. Conclusion: A strong superficial root system can provide the plant with water from scattered rains that occur with low frequency at the end of the growth period. On the other hand, the increase in the number of stomata along with their smaller size reduces leaf pores and enables a faster response of the stomata, and the rapid response of the stomata maximizes water use efficiency. Therefore, having a strong superficial root system along with high stomatal density can increase seed yield in dry conditions. [ABSTRACT FROM AUTHOR]

Background and Objectives: Parsley (Tagetes erecta) is an important bedding plant of asteraceae family. Environmental stresses, especially salinity stress in agricultural soils are increasing. Therefore, it seems necessary to find a suitable solution to reduce the effects of soil salinity and the possibility of cultivation in these types of soils. Meanwhile, growth-promoting bacteria are one of the important options as a factor to deal with these stresses. This research was carried out with the aim of the effect of growth stimulating bacteria as biofertilizers in making parsley plant resistant to salt stress. Materials and Methods: In order to investigate the effect of the application of growth-stimulating bacteria on reducing the effects of salinity stress in orange parsley, a research was conducted in the greenhouse of the Faculty of Agriculture of Zanjan University in 2022. This research was conducted as a factorial experiment in the form of a completely randomized design with treatments, three levels of salinity stress (0, 4 and 8 decisiemens) and three levels of Bacillus bacteria (control, Bacillus subtilis, Bacillus velezensis) in three replications, which in total It formed 27 experimental units. Morpho - physiologycal traits include: plant height, flower diameter, number of flowers, plant fresh weight, plant dry weight, root fresh weight, root dry weight, total chlorophyll, antioxidant, ion leakage percentage, peroxidase enzyme, proline, sodium, potassium and The ratio of sodium to potassium was calculated. Results: The results of this research showed that the effect of salinity stress as well as the effect of bacteria on all traits was significant. The interaction effect of salinity in bacteria was significant in some traits such as fresh and dry weight of roots, diameter and number of flowers, leaf ion leakage percentage, total chlorophyll, peroxidase enzyme, proline, sodium and potassium percentage and sodium to potassium ratio. Based on the results of the comparison of averages, due to salinity stress, plant height, fresh and dry weight of shoot and root, diameter and number of flowers, chlorophyll, potassium percentage decreased significantly and in contrast to the characteristics of flower ion leakage percentage, peroxidase enzyme level, Proline, anthocyanin and antioxidants, sodium and the ratio of sodium to potassium increased. Also, the use of bacteria moderated the negative effects of salinity stress and by increasing the amount of proline, anthocyanin, antioxidant and increasing the amount of potassium, it led to the improvement of growth conditions in 8 and 4 deci siemens per meter salinity stress. Among the bacteria that were used, Bacillus subtilis showed a better response than Bacillus velezensis in ornamental parsley and reduced the effect of salt stress. Conclusion: The results of this research showed that salinity induced negative effects on the morphological, physiological and biochemical characteristics of ornamental cabbage. Growth promoting bacteria reduced the negative effects of salinity stress through direct and indirect mechanisms. Among the bacteria that were used, Bacillus subtilis showed a better response than Bacillus velezensis in ornamental parsley and reduced the effect of salt stress. In other words, at high levels of salinity stress, the damage caused by salinity stress can be prevented by using growthpromoting bacteria. [ABSTRACT FROM AUTHOR]

Introduction and Objective: Black rust is one of the important fungal diseases that widely affects the quantity and quality of wheat in many regions of the world. The damages caused by black rust disease can be more than other pathogens in wheat and its importance is such that millions of hectares of healthy fields with high production potential can be destroyed in less time. Destroy it completely in one month. Resistance is one of the genetic characteristics of the host that plant breeders use to produce cultivars. Lines that are recognized as resistant in a survey can be used as a source of resistance in another breeding program. Genetic resistance reduces or eliminates the consumption of chemical poisons, and as a result, it is considered as the most economical and healthiest method of combating plant diseases. Accordingly, in order to statistically investigate some physiological markers related to resistance to black rust disease, 24 bread wheat genotypes including 8 cultivars and 16 promising lines were studied. In this study, two varieties MV-17 (disease-resistant variety) and Morocco (disease-susceptible variety) were selected as controls in this study due to their different behavior in resistance to wheat black rust. Material and Methods: This experiment was carried out in 2019 in the greenhouse of the Research Institute of Plant Breeding and Seed Preparation under the conditions of infection and non-infection with the native race TKTTF of wheat black rust disease and in the form of a randomized complete block design with four replications. Physiological traits including relative leaf water content (RWC), cell membrane stability (MP), electrical conductivity (EC), chlorophyll content (SPAD) and chlorophyll fluorescence were measured and recorded. Results: At the probability level of 1%, a significant difference between genotypes was observed and the interaction effect of disease x genotype was significant for all traits, which indicates the non-homogeneous difference of genotypes for the studied traits in two conditions of infection and non-infection. Also, for all measured traits, there was a significant difference between two different levels of disease infection, which shows the effect of the black rust pathogen on the relative content of leaves, membrane permeability, electrical conductivity, chlorophyll concentration, primary fluorescence, fluorescence It has maximum, variable fluorescence and photochemical efficiency of photosystem II. The results showed that pathogen contamination increases the relative water content, chlorophyll concentration, membrane permeability, initial fluorescence, maximum fluorescence, variable fluorescence, photochemical efficiency of photosystem II and decrease in electrical conductivity. Based on all studied physiological traits of genotypes MV-17, C-98-17, C-98-11, C-98-5, C-98-12, C-98-18, C-98-16, C-98-3 and CD-94-9 were identified as the genotypes that showed more resistance to the disease agent. There was a high correlation between initial fluorescence, maximum fluorescence, variable fluorescence, photochemical efficiency of photosystem II, membrane permeability and electrical conductivity in response to stem rust. Based on Ward's cluster analysis and detection function analysis, the genotypes were divided into four separate groups in the conditions of infection and non-infection with black rust. They were placed in a group. While, in the condition of no disease contamination, 6, 9, 4 and 5 genotypes were clustered in four separate groups, respectively. Conclusion: This study showed the effect of East Azerbaijan stem rust TKTTF race on the physiological traits of winter cultivars and lines of wheat. This race caused changes in the studied physiological traits in both experimental conditions, from this output it can be concluded that the resistant lines are more resistant to the disease than the commercial variety and are recommended as selected lines in breeding programs should be used. It is worth mentioning that according to the results of the grouping of genotypes and also the placement of valuable genotypes in terms of relative water content traits, membrane permeability index, chlorophyll content, initial fluorescence, maximum fluorescence, variable fluorescence, and photochemical efficiency. Photosystem II and electrical conductivity in the first and second groups in the conditions of disease infection and non-infection, it was concluded that the results of cluster analysis had a good relationship with the results of variance analysis and comparing the average of the studied traits. The results showed that the physiological traits measured in response to black rust disease have diversity. Therefore, possible genotypes with resistance to this pathogen can be identified by using the changes of these traits. Also, considering the relationship between the results obtained from the evaluation of physiological and pathological traits, the possibility of using physiological traits as indicators related to resistance to wheat black rust disease was benefited. In other words, the physiological indicators used were able to detect the existence of diversity and response to resistance to black rust disease and they can be used as physiological indicators related to resistance to black rust disease of wheat. Examining different traits in different environmental conditions has shown that the way the genotypes act and respond to the pathogen changes with the change of environmental conditions. For this purpose, these studies should be carried out in several years and in different environments. It is also recommended to carry out the above test using agricultural traits at the stage of the sorghum plant as well as biochemical traits related to the disease. [ABSTRACT FROM AUTHOR]

Introduction: Japanese barberry (Berberis thunbergii) is a perennial and woody shrub that grows in different regions of Iran and the world. The Berberidaceae family has a high potential in food and pharmaceutical industries due to its antioxidant, antimicrobial and anticancer activities. Elicitors are biotic or abiotic stimulators that can induce responses in plants. Abiotic elicitors are used to increase secondary metabolites in plants. Nanoparticles have minimum dimensions between one and 100 nanometers, which have specific physical and chemical properties. Like many nanoparticles, zinc oxide and cerium dioxide nanoparticles are toxic to living organisms. The mechanism of toxicity of nanoparticles is generally contributed to the induction of oxidative stress which lead to the formation of free radicals. Nanoparticles of zinc oxide and cerium dioxide can increase the antioxidant capacity of plants by stimulating oxidative stress. Material and methods: In order to study the changes in the physiological and biochemical characteristics of Japanese barberry under the influence of abiotic elicitors, an experiment was conducted in a completely randomized design with three replications in the greenhouse and laboratory of the Faculty of Agriculture and Natural Resources of Imam Khomeini International University in 2019. Treatments were included zinc oxide elicitors (0.1 g/L) and cerium dioxide nanoparticles (0.0002 g/L) and control (no elicitor). In this research, the amounts of protein, antioxidant enzymes and photosynthetic pigments in tissues of Japanese barberry were measured. Data analysis was done with SAS 9.1.3 statistical software. Comparison of means was done with Duncan's multiple range test and graphs were drawn using Excel software. Results and Discussion: The results of the data analysis of variance showed that the effect of treatment with cerium dioxide and zinc oxide nanoparticle elicitors on the amount of leaf protein, antioxidant activity and also the amount of photosynthetic pigments was significant. Comparison of the means showed that these two elicitors increased the leaf protein content by 26.2% and 12.4%, respectively, compared to the control, but they did not have a significant effect on the root protein content. Cerium dioxide decreased the activity of guaiacol peroxidase enzyme by 77.1% in the root; But in leaves, the activity of this enzyme increased by 134.8% due to treatment with zinc oxide. The highest activity of leaf superoxide dismutase enzyme (25.2% increase compared to control) was related to zinc oxide treatment. The lowest content of catalase enzyme in leaves and roots was obtained with cerium dioxide and zinc oxide. Zinc oxide increased the activity of leaf ascorbate peroxidase enzyme by 111.8%; In the root, the highest and lowest activity levels of this enzyme were obtained in the control and cerium dioxide treatments, respectively. Both elicitors significantly increased the leaf peroxidase enzyme activity compared to the control (128.6% and 157.1%, respectively); However, only the treatment with zinc oxide caused a significant increase of 25.5% in the activity of this enzyme in the root. The highest activity of glutathione reductase enzyme in leaf and root was observed in zinc oxide treatment (23.3% and 12.5% increase compared to control). Nano zinc oxide increased the amount of total chlorophyll and carotenoid in the leaves compared to the control by 93.4 and 67.5%, respectively. Conclusion: It was concluded that zinc oxide nanoparticles elicitor had the greatest effect in increasing the amount of photosynthetic pigments and enzyme activity. By using this elicitor in Japanese barberry culture, the amount of antioxidant enzymes can be increased and the extract can be used as a strong antioxidant in pharmaceutical products. [ABSTRACT FROM AUTHOR]

Introduction: Given the increasing demand for food due to population growth, besides the limited availability of arable land, the role of increasing production through plant breeding is evident. Maize is one of the key agricultural products in the world, a primary food source for humans and animals, and also used for biomass and bio-product production. Referring to the increased vigor of hybrids compared to their parents' heterosis can help to increase crop yields. Maize hybrids produced by crossing two or more pure lines have higher yields than pure maize. Therefore, the present study aimed to estimate heterosis and evaluate the coefficient of phenotypic and genetic variations and heritability in maize hybrids. Materials and methods: The plant materials included the maternal parent (MS02), the paternal parent (TS01), and the SC01 offspring evaluated during the 2023 growing season at the Agricultural and Natural Resources Research and Education Center of Ardabil Province (Moghan) in a randomized complete block design with four replications. Agrophysiological traits included plant height, grain yield, pigment content, stomatal conductance, and chlorophyll fluorescence, antioxidant defense system traits included proline, polyphenols, malondialdehyde, hydrogen peroxide, soluble protein, and antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT). Analysis of variance (ANOVA) was performed to estimate the coefficients of phenotypic and genetic variations, general heritability, and heterosis based on the mean of parents and the superior parent. Results: The analysis of variance showed significant differences among the genotypes (MS02×TS01; SC01) in terms of the studied traits. The difference between genotypes was significant for all agro-physiological traits and antioxidant defense systems except for chlorophyll a, Fm, Fv and Fv/Fm. According to the results, among the studied traits, chlorophyll fluorescence (Fm) and hydrogen peroxide content had the highest mean values, error variance, genetic variance, and phenotypic variance compared to the other traits. Moreover, the CAT enzyme had the highest error variance, genetic variance, phenotypic variance, genetic diversity coefficient, and phenotypic diversity coefficient among the antioxidant enzymes. These results indicate that heterosis could significantly improve the morphological traits of F1 hybrid maize (SC01). Furthermore, high genotypic variance for most traits shows a high potential for improving these traits through plant breeding. The range of heterosis variations (relative to the mean of parents) among the evaluated traits was between -0.04 and 95.19, indicating the diversity of heterosis levels among the evaluated traits in the SC01 hybrid. Conclusion: Given the observed diversity in the present study, indicating the presence of alleles with dominance effects in agrophysiological traits and traits related to the antioxidant defense system, as well as the desirable diversity and heritability in agrophysiological traits and antioxidant defense systems, there are differences between the maternal and paternal lines of the SC01 hybrid. It seems that using agro-physiological traits and antioxidant defense systems may be useful in determining the best crosses to maximize heterosis in maize. The observed heterosis provides an opportunity to develop new hybrids with better performance and quality. Selecting genotypes with desirable alleles and suitable parents with high genetic diversity is an effective strategy for hybrid maize breeding that may result in increased grain yield and improved photosynthetic efficiency. [ABSTRACT FROM AUTHOR]

Drought stress is one of the most important abiotic stresses limiting wheat production. To improve the growth and yield of wheat under drought stress, a factorial experiment was performed based on a randomized complete block design with three replicates in the research greenhouse of the University of Tehran. Experimental treatments included irrigation at two levels (well-watered and drought stress) and vitamin foliar application at four levels (control, thiamine, pyridoxine, and thiamine+pyridoxine). The results showed that drought stress reduced the relative water content of flag leaves by 21%. The use of vitamins increased the amount of this trait compared to the control treatment. The chlorophyll number (SPAD) of flag leaf increased under drought stress, but the use of vitamins had no significant effect on this trait. Drought stress had an increasing effect on leaf free proline content and foliar application of thiamine and its combination with pyridoxine, respectively, increased this trait by 53% and 32% compared to treatment without foliar application under drought stress conditions. Also, the percentage of electrolyte leakage and malondialdehyde content of flag leaf under drought stress increased by 31% and 103%, respectively. Vitamins reduced the amount of malondialdehyde and had no significant effect on the percentage of electrolyte leakage. Drought stress also reduced wheat grain and biological yields. Foliar application of vitamins showed an additive effect on these traits compared to the control treatment. The highest grain yield per plant was obtained in treatments of pyridoxine (1.1 g) and its combination with thiamine (1.2 g). [ABSTRACT FROM AUTHOR]

Water and soil salinity is one of the reasons for the reduction of cucumber yield. In order to verify the feasibility of using two non-commercial rootstocks to increase salinity resistance in cucumber and compare it with the commercial rootstock of Cobalt RZ F1, an experiment was conducted in the research farm of agricultural faculty of Arak University in a factorial experiment based on randomized complete block design. The first factor was salinity stress at three levels (no stress, 30 mM and 60 mM NaCl) and the second factor was rootstocks at four levels included nongrafted cucumber, colocynth (Citrullus colocynthis), kiwano (Cucumis metuliferus) and Cobalt (C. maximaxC. moschata). The results showed that increasing the amount of salinity led to a significant decrease in the stem length, stem, leaf and fruit dry weight percentage. The Cobalt rootstock had the highest stem length, the highest length to fruit width ratio and the lowest increase in malondialdehyde content under salinity stress. The colocynth rootstock had better performance in terms of dry weight percentage of stem, total leaf chlorophyll, leaf carotenoid, relative leaf water content and reduction of leaf sodium content in saline conditions compared to other rootstocks and non-grafted cucumber. The highest amounts of total phenol content, leaf potassium content and percentage of leaf and fruit dry weight were observed in grafted cucumber on kiwano rootstock. The results showed that colocynth and kiwano rootstocks can be introduced as suitable and compatible rootstocks to increase salinity tolerance in grafted cucumbers. [ABSTRACT FROM AUTHOR]

This study investigated the effects of simultaneous salinity and heat stress on some physiological and vegetative characteristics in peppermint. The effect of three levels of salinity (0, 60 and 120 mM of sodium chloride) and two levels of thermal stresses (25°C and 35°C) at 24, 48 and 72 hours after treatments were measured on some physiological and morphological characteristics of Mentha piperita L. in a completely randomized design with three replications. The results showed that simultaneous salinity and heat stress increased the relative levels of phenolic and proline compounds. At 35 ° C and 120 mM salinity, the amount of proline increased by 2.32, 2.5 and 1.92 times compared to the control at 24, 48 and 72 hours, respectively. The highest accumulation of phenolic compounds was observed at 35 ° C and salinity of 120 mM after 72 hours equal to 3.3 mg/g. The content of soluble sugar, carotenoids, total chlorophyll and calcium in peppermint seedlings had a decreasing trend. At 120 mM salinity, the ratio of K+/Na+ compared to the control decreased by 8.44, 10.37 and 9.35 times in 24, 48 and 72 hours, respectively. Salinity and heat stress decreased the fresh and dry weight of shoots, but in contrast, the fresh weight and dry weight of roots showed a significant increase. Simultaneous salinity and heat stresses are limiting factors for the cultivation of peppermint. The simultaneous stress of salinity and heat increased the amount of phenol, which could improve the quality of peppermint..

Medicinal plants, as important agricultural products, can be considered as the greatest national wealth for any country because of their vital role in promoting national goals for health and also as genetic treasures. Having a diversity of climates, Iran has a great variety of medicinal plants. Detecting the growth status of medicinal plants under drought stress conditions can lead to the cultivation of resistant plants in dry or semidry areas. In the present study, we investigated the morphological and physiological responses of ten ecotypes of the medicinal plant Teucrium polium L. native to southeastern Iran under drought stress. For this purpose, a factorial greenhouse experiment was conducted in a completely randomized design with three replications. In this experiment, moisture treatments of 100, 70, and 40% of field capacity were applied. Analysis of the data showed that the morphological traits under study including stem length and fresh and dry weight of shoots decreased by 5% with increasing drought stress. Drought stress also increased root length, proline content, and phenolic compounds while decreasing chlorophyll a, b, total chlorophyll, and protein contents. The highest resistance to stress was shown by ecotypes growing in Sarcheshmeh and Kuhpayeh regions and the lowest resistance was shown by plants in Shahdad and Anbarabad regions. The results of the study indicated the relative resistance of this plant to drought stress. Therefore, it is a very suitable medicinal plant for cultivation in dry and low water areas of Iran. Among the studied ecotypes, the plants of Sarcheshmeh and Kuhpayeh regions responded 40% better to drought stress conditions and cultivation of these ecotypes in stressed areas can be recommended with more confidence.

Salinity stress is one of the most important of abiotic stress that affects the yield of oilseed rape. In order to study some physiological and biochemical changes and BnaCDPK14 transcript expression in rapeseed (Brassica napus L.), two tolerant cultivars (Slm046 and Zarfam) and two susceptible cultivars (Okapi and Sarigol) were planted in a growth chamber and were irrigated by water including 100 and 200 mM NaCl and normal water. Relative water content, electrolyte leakage, antioxidant enzyme guaiacol peroxidase (GPOX), antioxidant enzyme catalase (CAT) and the expression of calcium-dependent protein kinase 14 (BnaCDPK14) were measured. The results indicated the relative water content and electrolyte leakage (200 mM NaCl) decreased and increased under stress respectively. The antioxidant enzyme guaiacol peroxidase (GPOX), catalase (CAT) and BnaCDPK14 increased by salinity stress, tolerant cultivars showing more increase. Negative correlation was observed between the relative water content of leaves and electrolyte leakage. There was a high positive correlation between the guaiacol peroxidase and catalase contents and the expression of BnaCDPK14, indicating that by increasing the reactive oxygen species under stress, the plant enzymic antioxidant system helps the plant to cope with it. Salinity stress is one of the most important of abiotic stress that affects the yield of oilseed rape. In order to study some physiological and biochemical changes and BnaCDPK14 transcript expression in rapeseed (Brassica napus L.), two tolerant cultivars (Slm046 and Zarfam) and two susceptible cultivars (Okapi and Sarigol) were planted in a growth chamber and were irrigated by water including 100 and 200 mM NaCl and normal water. Relative water content, electrolyte leakage, antioxidant enzyme guaiacol peroxidase (GPOX), antioxidant enzyme catalase (CAT) and the expression of calcium-dependent protein kinase 14 (BnaCDPK14) were measured. The results indicated the relative water content and electrolyte leakage (200 mM NaCl) decreased and increased under stress respectively. The antioxidant enzyme guaiacol peroxidase (GPOX), catalase (CAT) and BnaCDPK14 increased by salinity stress, tolerant cultivars showing more increase. Negative correlation was observed between the relative water content of leaves and electrolyte leakage. There was a high positive correlation between the guaiacol peroxidase and catalase contents and the expression of BnaCDPK14, indicating that by increasing the reactive oxygen species under stress, the plant enzymic antioxidant system helps the plant to cope with it. Salinity stress is one of the most important of abiotic stress that affects the yield of oilseed rape. In order to study some physiological and biochemical changes and BnaCDPK14 transcript expression in rapeseed (Brassica napus L.), two tolerant cultivars (Slm046 and Zarfam) and two susceptible cultivars (Okapi and Sarigol) were planted in a growth chamber and were irrigated by water including 100 and 200 mM NaCl and normal water. Relative water content, electrolyte leakage, antioxidant enzyme guaiacol peroxidase (GPOX), antioxidant enzyme catalase (CAT) and the expression of calcium-dependent protein kinase 14 (BnaCDPK14) were measured. The results indicated the relative water content and electrolyte leakage (200 mM NaCl) decreased and increased under stress respectively. The antioxidant enzyme guaiacol peroxidase (GPOX), catalase (CAT) and BnaCDPK14 increased by salinity stress, tolerant cultivars showing more increase. Negative correlation was observed between the relative water content of leaves and electrolyte leakage. There was a high positive correlation between the guaiacol peroxidase and catalase contents and the expression of BnaCDPK14, indicating that by increasing the reactive oxygen species under stress, the plant enzymic antioxidant system helps the plant to cope with it.

An experiment was performed to investigate the effects of using saturated and unsaturated fatty acids calcium salts on the production performance and some physiological traits of finishing lambs fattened under heat stress condition. Thirty-two cross bred Lori-Bakhtiari X Romanov lambs were randomly divided into 4 groups. Lambs were fed individually with the following experimental diets for 6 weeks (early July to mid-August): 1) Basal diet without supplemental fat (control), 2) Basal diet supplemented with 2% (on DM basis) of fish oil calcium salt, 3) Basal diet supplemented with 2% (on DM basis) of olive oil calcium salt and 4) Basal diet supplemented with 2% (on DM basis) of saturated fat calcium salt. Daily feed intake was recorded and lambs body weight was measured weekly. Rectal temperature and respiration rate were measured once per week. Using calcium salts of fish oil, olive oil and saturated fats in the diet significantly increased daily weight gain and reduced the lambs feed conversion ratio compared to control group (P< 0.05), but had no effect on dry matter intake of the Lambs. Regardless of fatly, acid origin, supplementing lambs with calcium salts of fatly, acids, reduced rectal temperature and respiration rate of lambs exposed to heat stress, compared to control group (P< 0.01). Also, using calcium salts of Fish oil, olive oil and saturated fat had no effect on DM, CP and EE digestibility, however, EE digestibility, was higher in lambs consumed fat-supplemented diets than the control group. NDF digestibility, was significantly higher in the control group lambs than the other groups. The results of this study showed that diet supplementation with calcium salts of unsaturated fatty acids of fish and olives and saturated fatty acids, improved the production performance of finishing lambs exposed to heat stress. No difference was detected between fat supplements with different fatty acid patterns, in this investigation. [ABSTRACT FROM AUTHOR]

Zagros forests with an area over six million hectares are important for economic, social and environmental aspects. More than one million hectare of Zagros forests has been declined. This research was carried out by selecting six sites at different altitudes and slopes. At each site, 30 oak (Quercus brantii) trees were selected. Sampling was done at any point on a certain level with an area of 20 hectares. It was achieved in June and October and 20 elemental parameters were measured. In order to investigate the relationship between ionomics and oak decline, oak stands were classified into healthy, endangered, and damaged bases. The results of univariate analysis of variance based on three factors of season, region, and crown health index showed a significant difference in the number of elements such as N, P, C, K, C / P, C / K, Fe, Ca, Mg, Na, Cu, Mn, Zn, Si in spring and autumn (P

In order to determine the water requirement of sunflower cultivars, an experiment was conducted during 2015-2016 at Ardestan Station, Isfahan. The experiment was carried out in a factorial randomized complete block design with four replications. Treatments included 3 irrigation regimes (D1: irrigation after 60 mm, D2: irrigation after 120 mm, D3: irrigation after 180 mm evaporation from small tub evaporation) and 5 sunflower cultivars (Azargol, Prograss, Gabur, Hysan 25, and Hysan 36). Results showed that under non-stress and moderate stress, Azargol and Prograss cultivars had the highest rate, in terms of seed filling period, the weight of 1000 grains, stem diameter, and head diameter. Under severe stress, Prograss and Gabur cultivars were remarkable, so that Prograss cultivar had the highest seed filling period, weight of 1000 grains, stem diameter, and Gabur cultivar had the highest number of budding, number of flowering, and stem diameter. In the study of physiological characteristics, results showed that under non-stress and moderate stress chlorophyll a, b, total chlorophyll, and net-photosynthesis in cultivars Progerass and Gabor were significantly increased compared to other cultivars. In severe stress conditions, the Progress and Gabor cultivars in chlorophyll a, b and total chlorophyll content were superior to other cultivars. The results of proline analysis indicated that proline leaf content increased significantly with water stress. Among the cultivars under severe stress conditions, proline leaf content in Progerass and Gabor cultivars was significantly higher than other cultivars. The results of this study showed that Azargol, Gabor, and Progerass cultivars are more tolerant than Hysan 25 and Hysan 36.

In this research, considering the importance of drought and canola, an experiment was done as factorial in a Randomized Complete Block Design using ten spring canola cultivars with hydroponic method in seedling stage and with induced of drought stress by PEG6000. Two weeks after of the stress induction and at the end of the rossete stage, samples were taken. The results showed that the value of morphological and physiological traits was declined under drought stress. Also the studied cultivars were varied in response to drought stress and in general, the most tolerant and sensitive cultivars for studied traits were SW5001 and Sarigol cultivars, respectively that to graduate studies on these two cultivars proteome analysis was performed. To study the pattern of protein, extraction of protein from leaf tissue was performed and the first dimension electrophoresis using IPG strips and second dimension electrophoresis was performed by SDS-PAGE technique and after the gels staining with commassie blue, gels imaging with scanner and protein analysis with PDQuest software was done. Finally a total of 25 protein spots between control plants and under drought stress for both cultivars were detected that of these, 15 protein spots were common between two cultivars and six unique protein spots for tolerant cultivar and four unique protein spots for susceptible cultivar. After detection these proteins with mass spectrometry, overall, the most common protein groups between two cultivars were involved proteins in photo-reaction of photosynthesis, Calvin cycle and detoxifying enzymes. In total, the most important cause of the sensitivity and tolerance of canola cultivars different expression and unique expression of proteins into cultivars and finally effects of them on other were obtained.

مقدمه و هدف استفاده از امواج فراصوت به عنوان یک تکنولوژی نوین شناخته می­شود. از آن برای اهداف متعددی از جمله صنعت، کشاورزی (به عنوان مثال، اصلاح نباتات، فرآوری کشمش) و تکنولوژی غذایی استفاده می­گردد. شواهد آزمایشی حاکی از آن است که پرتودهی بذر با فراصوت تأثیر فوق­العاده ­ای بر رشد گیاه­چه به جای می­گذارد. به عنوان نمونه گزارش شده است که پرتودهی بذر به مدت 50 تا 60 ثانیه، درصد جوانه ­زنی، طول ریشه­ چه و ساقه­ چه را به ترتیب 40، 32 و 5 تا 8% افزایش می­دهد (Fariabi et al., 2008). پرتودهی Myrtus communis منجر به شکسته شدن دورمانسی، افزایش سرعت جوانه­زنی و بیشتر شدن وزن خشک گیاه­چه شده است (Alvandian et al., 2013). بیشتر آزمایشات مربوط به پرتودهی، به جوانه ­زنی و رشد اولیه گیاه­چه معطوف شده است. در نتیجه، گزارش منتشر شده ­ای در خصوص تأثیر احتمالی آن بر گیاه در مابقی مراحل رشد و نمو در دست نیست. به لحاظ تأثیر مثبت پرتودهی بر رشد ریشه ­چه، این فرضیه مطرح است که این اثرات، در مراحل بعدی یعنی مراحل رشد و نمو گیاه بالغ نیز منعکس می­گردد. در نتیجه، به علت سیستم ریشه­ا ی عمیق­تر احتمالی، ممکن است یک افزایش مقاومت به خشکی ایجاد گردد. هدف از این آزمایش مزرعه­ای این بود که ببینیم آیا پرتودهی می­تواند اثرات مضر تنش خشکی بر ذرت را بکاهد یا خیر. مواد و روش­ها واریته مورد استفاده ذرت، SC740بود. آزمایش به صورت فاکتوریل در قالب طرح بلوک­های کامل تصادفی با سه تکرار اجرا گردید. تیمارها شامل تنش خشکی {شاهد، تنش طولانی مدت (قطع آبیاری از گلدهی به بعد) و تنش کوتاه مدت (قطع آبیاری از مرحله خمیری شدن دانه به بعد)} و پرتودهی بذور با فراصوت (شاهد، 2، 4، 6 و 8 دقیقه) بود. صفات مورد بررسی شامل شاخص سطح برگ، محتوای نسبی رطوبت (RWC)، محتوای کاروتنوئید برگ، محتوای قندهای محلول برگ و محتوای پتاسیم برگ بود که 10 روز پس از مرحله خمیری شدن دانه اندازه گیری شدند. بعد از رسیدگی، محتوای پروتئین دانه، بیوماس اندام هوایی و عملکرد دانه مورد سنجش قرار گرفتند. نتایج و بحث نتایج نشان داد که در بین منابع تغییر (فاکتورهای آزمایش در جدول ANOVA)، تنها اثر ساده تنش خشکی و پرتودهی بر RWC معنی­دار بود. کاهش RWC بر اثر تنش خشکی کوتاه مدت و بلند مدت به ترتیب برابر با 13 و 19% بود. شش دقیقه پرتودهی به عنوان بهترین سطح پرتودهی توانست RWC را در مقایسه با شاهد به میزان 18% افزایش دهد. به طور تعجب آور، شاخص سطح برگ تحت تأثیر پرتودهی قرار نگرفت ولی در سطح احتمال 1% از تنش خشکی تأثیر پذیرفت. کاهش ناشی از تنش خشکی کوتاه مدت و بلند مدت در این شاخص به ترتیب برابر با 25 و 27% بود. تفاوت شاخص سطح برگ در دو سطح تنش خشکی معنی­ دار نشد. بر همین اساس به نظر می­رسد که ممکن است دو سطح تنش از لحاظ ضخامت (وزن خشک) برگ تفاوت داشته باشند. بالاترین محتوای پتاسیم برگ در شرایط تنش بلند مدت (299.33 mg.g-1) به دست آمد. گیاهان (بذور) پرتودهی شده به مدت 6 دقیقه نسبت به شاهد از 14% پتاسیم بالاتر برخوردار گردیدند. در خصوص محتوای قندهای محلول، تنش خشکی کوتاه مدت بالاترین تأثیر را داشت و در شاهد، کمترین مقدار آن حاصل شد. شش دقیقه پرتودهی به عنوان بهترین سطح پرتودهی، محتوای پتاسیم برگ را به میزان 22% افزایش داد. محتوای کاروتنوئید برگ تنها به تنش خشکی واکنش نشان داد؛ با افزایش شدت تنش، مقدار آن روند کاهشی نشان داد. اعتقاد بر این است که در واکنش به تنش خشکی، محتوای کاروتنوئید افزایش می­یابد ولی بعد از آن کاهش نشان می­دهد که نوعی واکنش سازگاری گیاه به تنش می­باشد (Young, 1991). محتوای پروتئین بذر به اثرات ساده و متقابل فاکتورها واکنش معنی­داری نشان داد. این امر ثابت می­کند که اثر تنش خشکی بر این صفت در گیاهان پرتودهی شده به میزان­ های مختلف، یکسان نیست. به عنوان مثال، در شرایط پرتودهی 2 و 8 دقیقه، محتوای پروتئین بذر برای گیاهان تنش دیده کمتر از شاهد بود. ولی برای 6 دقیقه پرتودهی، عکس این حالت وجود داشت. بالاترین محتوای پروتئین بذر مربوط به ترکیب تیماری تنش بلند مدت و 6 دقیقه پرتودهی بود. کاهش بیوماس در شرایط تنش کوتاه مدت و بلند مدت به ترتیب 24 و 31% بود. برای عملکرد دانه، این کاهش به ترتیب برابر با 18 و 34% شد. بهترین سطح پرتودهی، یعنی 6 دقیقه، بیوماس و عملکرد دانه را به ترتیب 13 و 25% افزایش داد. نتیجه ­گیری اثرات متقابل خشکی و پرتودهی بر برخی صفات شامل بیوماس و عملکرد دانه معنی­دار نبود. این یافته نشان می­دهد که اثر مثبت پرتودهی بر رشد ذرت در شرایط وجود و عدم وجود تنش، تفاوتی ندارد. به بیان دیگر، پرتودهی بذور به مدت 6 دقیقه می­تواند رشد ذرت تنش دیده و تنش ندیده را بیشتر نماید. این امر معادل تسکین (کاهش) اثرات خشکی بر ذرت است. این تسکین دهندگی ممکن است مربوط به افزایش محتوای پتاسیم برگ (14%) و افزایش محتوای قندهای محلول برگ (22%)، و در نتیجه بهتر شدن محتوای آبی گیاه (18% افزایش در RWC) باشد.

Introduction: Climate change has great impact on global production of several major plants. Negative effects of increasing carbon dioxide concentration in the world, on the one hand, and positive effects of the gas on plants, on the other hand, are the most important reasons for investigating the gas effects on different plants. Many studies have been conducted to examine the effects of elevated CO2on plants during the past several decades. Carbon dioxide enrichment in greenhouses can be used as a mechanism for reducing production time, improving quality and increasing plant vigor. The world is facing an increase in the concentration of carbon dioxide in the coming years. The physiological responses of plant are affected by CO2concentration,among which changes in nitrogen, chlorophyll content, proline and soluble sugar have been observed in many studies. The significant changes in the levels of these characteristics are likely to cause marked effects on the entire metabolism of plant. Since the proteins of the Calvin cycle and thylakoid represent the majority of leaf nitrogen, chlorophyll content is the central part of the energy manifestation and can directly determine photosynthetic response and primary production. This study was aimed to investigate the effects of elevated concentration ofCO2 on some morphological and physiological traits of Melia azedarachunder greenhouse conditions. . Materials and Methods: The experiment was conducted in a CO2 – controlled glasshouse in a completely randomized design with three replications in Yazd University. The glasshouse consisted of three separate chambers with threeCO2levels of control (450 ppm), 750ppm, and 1100ppm.The concentration of CO2within each chamber was monitored constantly three times a week. After two months, morphological characteristics such as diameter of the collar, height of stem, number of leaves, wet weight of shoots, root wet weight, wet matter biomass, dry weight of shoots, root dry weight, dry matter biomass, and physiological characteristics including proline content of leaves, soluble sugar of leaves, a andb chlorophyll content, total chlorophyll content, carotenoid, nitrogen, phosphorus, potassium and water content of leaves were measured. To analyze the data, normality was assessed using Kolmogorov–Smirnov test. Analysis of variance was performed to detect the difference between the different levels of treatment for all traits. Difference among treatments means were compared by using Duncan test. All the analyses were performed using SAS statistical software. Results and Discussion: The results showed that CO2at the concentrations of 750 and 1100 ppm affected significantly all the measured morphological properties except for plant height, root dry weight and physiological traits such as proline, N, and leaves relative water content. However, CO2concentration of 750 ppm had the highest effect on the studied parameters, so that mean dry weight of shoot, dry matter biomass and proline increased up to more than three times, and shoots and roots wet weight and wet matter biomass increased up to more than two times compared to control. The greatest diameter of the collar and the amount of nitrogen were observed at 750 ppm concentration. Concentrations of 750 and 1100 ppm caused a significant increasein the number of leaves (up to two times) and the height of stem compared to control. The increase observed inmorphological characteristics may be owing to photosynthesis stimulation during the experiment in CO2-elevated chamber. Soluble sugar as an important product of photosynthesis increased but the differences were not significant. Soluble sugar may be used for synthesis of morphological characteristics. Conclusion: Growth of Melia azedarach in elevated-CO2 chamber strongly reacted to theincrease in photosynthesis. Therefore, based on the results of this study,CO2 elevation in glasshouse can be proposed for increasing the growth of plant. Consideringthe continued increaseinCO2 concentrations as a result ofcontinued use of fossil fuels in the word, cultivation of Melia azedarach in urban areas seems an appropriate option. The results of the present study also showed that there is not generally a significant difference between CO2concentrations of 750 and 1100 ppm in Melia azedarach. Therefore, it can be concluded that CO2 up to 750 ppm can cause a significant increase in the growth of this species, because no significant effect was observe between the two concentrations (750 and 1100 ppm) on growth factors.

In the current study, the genetic variability and effect of some agronomic traits on grain yield of 218 Iranian wheat landraces were evaluated under normal irrigation and drought stress conditions employing alpha-lattice design with two replications on the research field of Agronomy and Plant Breeding at the University of Tehran during the year of 2016-2017. Results of data analysis of variance demonstrated that there were significant differences among landraces in the investigated traits including phonologic and physiologic traits, yield and yield components in both conditions. According to descriptive statistics results, the highest phenotypic variation of landraces observed in seed number per spik e, and the least variation in spik e weight. The findings on phenotypic correlations, stepwise regression, and path coefficient analysis sustain the important role of spik e weight, seed number per spik e and thousand grain weight in the grain yield in both normal irrigation and rain-fed conditions. In addition, considered traits had the highest impact on the grain yield directly and indirectly under both conditions. The result of principle component analysis presented a positive correlation between the first component and seed number in both conditions, while the second component had a positive relationship with phonological traits in normal irrigation and leaf greenness in rain-fed conditions. [ABSTRACT FROM AUTHOR]

Almond is highly sensitive to salt stress and one way to reduce the negative effects of this type of stress is to select a tolerant rootstock/scion. Keeping these in mind, the present experiment investigates the effects of salinity stress on some morphological, physiological, and nutritional traits of almond rootstocks with the help of a factorial experiment, conducted at Horticultural Research Institute in 2017, which was based on a completely randomized design with two factors (eight levels of rootstock/scion compositions and five levels of salinity) and in three replications. Results show that by increasing salinity from zero to eight ds/m, the highest and lowest amount of reduction in root dry weight can be observed in 'Shahrood 12'/Tetra (37.8%) and GN15 (14.5%), respectively. Also, the lowest and highest dry weight loss in the main branch can be seen in bitter almond seedling (38.2%) and 'Shahrood 12'/GN15 (47.9%), respectively, with the highest amount of necrosis, observed in bitter almond seedling (28.98%) and the lowest value in 'Shahrood 12'/GF677 (9.9%). Based on the experiment, the lowest and highest changes in electrolyte leakage occurred at the rootstock of GF677 (30.74%) and GN15 (42.93%) with the lowest and the highest changes in sodium belonging to 'Shahrood 12'/GF677 (51.2%) as well as bitter almond seedling (82%), respectively. The results also show that by increasing salinity stress, the amount of root and leaf nutrient elements ascends initially, then to drop as salinity levels are increased further. Based on the results, 'Shahrood 12'/GF677 is the most tolerable combination and 'Shahrood12', grafted on bitter almond seedling, is the most sensitive to salt stress. [ABSTRACT FROM AUTHOR]

We conducted a glasshouse experiment as a factorial in randomized study with six replications on pasture species of Schoenoplectus triqueter in Gonbad Kavoos University from 2012-2013. Treatments included height waterlogging in four levels (control, equal to the water surface, 10 cm below the water surface, 20 cm below the water surface) and waterlogging period over three levels (10, 20 and 30 days). In this investigation, we measured the morphological traits (length root, the number of rhizome, length rhizome, the number of internode, dry weight of root, dry weight of rhizome, the number of shoot stems and shoot dry weight) and physiological traits (proline and chlorophyll content). The results showed that the contraction effect of period × height waterlogging was significant in 1% level on all studied traits expect for root volume. We observed increased length and dry weight of root, the number of rhizome, length rhizome, number of internode, and number of shoot stems at a treatment of 10 cm below the water surface in three periods of waterlogging and with an increase of waterlogging period. The highest proline and chlorophyll contents were observed in the control group and the group with 10 cm below the water surface. This species could be introduced to flood resistance.

Introduction: The German chamomile (Matricaria recutita L.) is mainly cultivated for essential oil. Nowadays, it is a highly favored and much-used medicinal plant in reqular and traditional medicine. Water deficit is one of the most important limiting factors on crops production in arid and semi-arid regions (Sharafi et al. 2002). Drought stress limits the growth of plants by reducing water content of tissues and causes some metabolic and physiological changes. On the other hand, the availability of nutrients in the soil is affected by drought stress. Thus, nutritional management of plants under drought stress conditions is one of the most important factors in crop production. A better understanding of the role of nutrients in plant resistance to drought is associated with improvement of fertilizer management in arid and semi-arid areas. Our objectives were to investigate the effects of phosphorus and zinc fertilizers on nutrient content and essential oil yield of German chamomile under drought stress. Material and Methods: The experiment was conducted in split plot factorial based on randomized complete block design with three replications at Research farm of University of Zabol in 2013. Drought stress consisted of three levels 75% (control), 50% (mild stress) and 25% of field capacity (severe stress) as main plots, and factorial combinations of three triple superphosphate fertilizer (CaH4P2O8) levels (0, 150, and 300 kg ha-1) and two zinc sulphate fertilizer (ZnSO4H2O) levels (0 and 30 kg ha-1) as sub plots (the fertilizers were applied before planting time). The seeds were sown at 20 cm apart in rows 40 cm wide, on first half of March 2013. Drought stress levels were determined by the Time Domain Reflectometry (TDR). The success of chamomile cultivation as a commercial venture lies in how efficiently and effectively one can collect the flowers at the right stage during the peak flowering season extending over a period of 3–6 weeks. So, flowers were selectively collected on 27 April, 30 April, 4 May, 8 May, and 12 May 2013. German chamomile essential oil was extracted from the dried flowers and using Clevenger system. In the study, the content of potassium, sodium, zinc, phosphorus, chlorophyll a, chlorophyll b and essential oil yield were measured. Statistical analysis was carried out using SAS software (version 9.1). Significant difference was set at P ≤ 0.05 and determined using the Duncan's multiple-range test. Results and Discussion: The results showed that exposing chamomile plants to soil moisture stress during its life cycle might lead to a significant effect on essential oil yield and the nutrient content except zinc and phosphorus. The phosphorus fertilizer also affected the content of potassium, sodium, zinc, phosphorus, chlorophyll and essential oil yield while the zinc fertilizer just affected zinc and phosphorus content, chlorophyll b and essential oil yield significantly. Also, we observed that high application of phosphorus fertilizer (300 kg ha-1) had a negative effect on yield of chamomile. This plant growth disorder is maybe because of interaction between P and Zn that is usually termed ‘P-induced-Zn deficiency’. This disorder in plant growth is associated with high levels of available P or with application of P to soil. Thus, it is important that the application of nutrients to be in balance. Having a good nutrient balance is therefore an important factor to improve plant growth by indicating the actual amount and the combination of nutrients that the production needs. Also, this is a good way to save money. In summary, the results of this study indicated that drought stress caused significant effects on physiological traits, essential oil yield and nutrient content. The results showed that optimum amount of Zn and P can improve the studied traits of chamomile. According to the results of this experiment, it seems that the application of Zn under drought stress condition can decrease damage of drought stress that this is maybe because of the critical role of that in plant nutrition and production. Conclusion: In general, the results suggested that irrigation based on 50% of field capacity with application of 150 kg phosphorus fertilizer ha-1 and 30 kg zinc fertilizer ha-1 can improve essential oil yield and medicine components of German chamomile essential oil.

In order to study the effect of drought stress on seed yield and some physiological and biochemical characteristics of different genotypes of red bean an experiment was performed in split plot based on randomized complete block design with three replications at the research field of Islamic Azad University, Arak. The main plot factor was irrigation surfaces (normal and stress); irrigation was cut in flowering and pod filling and the sub plot factor was red bean genotypes including Derakhshan, D81083 and Goli. The Analysis of Variance showed that the draught stress significantly affected leaf relative water content, electrical conductivity of the cell membrane, leaf proline content, protein content, concentration of soluble sugars. Goli genotype had the highest relative water content, protein content and D81083 and Derakhshan genotype had the highest proline content and lowest electrical conductivity of the membrane was proline the result of the experiment indicates the stability of the cell membrane. Derakhshan and D81083 genotypes contained highest soluble sugars. D81083 and Goli genotypes showed their superiority in traits under study in this experiment and therefore can be cultivated in areas where there is water shortage.

Walnut has a high economic value because of the good quality of wood and fruits. So this species has been harvested since many years ago till today and has been introduced as a protected species. The performance of Juglans regia increases in wet years, but reduces in dry years, hence paying attention to physiological and morphological parameters in order to identify the genomic regions related to drought resistant is important for breeding programs in walnut. In this study, genetic diversity by SSR markers has been evaluated. Also, the association of used primers with physiological and morphological traits were analyzed before and after drought stress. 10 SSR primer pairs generated 53 alleles in 62 walnut seedlings. All locies showed significant difference (p≤0.01) from the Hardy-Weinberg. Dendrogram of the Neighbour-Joining method showed that 62 walnut seedlings divided to four main groups. Analyses of population structure by Structure 2.3.1 software identified two sub populations (k=2). Based on association mapping analysis, by using MLM (mixed liner model) method, transpiration, conductance and photosynthesis have been controlled by WGA9 and WGA69 locies in normal condition. In stress condition WGA1 loci showed relationship with CO2 concentration that was covered %75 of variations of this trait. The results of this study can be used in breeding programs of Juglans regia to identify drought resistant varieties.

Drought one of the most important global threats against bread wheat production. In order to identify physiological traits associated with drought tolerance, 52 bread wheat varieties were cultured under two normal and drought stress condition in a randomized complete block desigen with three replications. RWC (in three independent times), leaf rolling, leaf silvering, days to flowering, days to maturity and stem reserve remobilization were investigeted. Also in a pot experiment osmotic adjustment of the varieties were measured at seedling stage. varieties Star and Bezostaya had the highest RWC (0.79 and 0.78, respectively). Osmotic adjustment in Rasol and Unknown11 were highest (0.58 and 0.56, respectively). Varieties Tipik, Unknown11 and Azar2 showed the least decrease in thousand grain weight after spraying with KI (4.8, 5.5 and 5.5, respectively). Also varieties Dez, Gaspard and MV-17 have the highest degree of leaf silvering and varieties Niknejad, Star and Kohdasht under drought stress were able than the other varieties bring their leaves to form a rolling and cope with water deficit. Under drought stress, Varieties Alborz, Zagros and Inia were observed premature than the other varieties and Gaspard and Kaslojen varieties were observed late mature than the other varieties. Altogetehr varieties Kohdasht, Star and Bezostaya can be used as genetic resources for leaf water retention under drought stress condition for imjproving other varieties. Also as Azar2 and Unknown11 had highest amount of thousand grain weight under normal condition and simoultanously showed high ability in stem reserves remobilization they can be selected as parents in crosses for improving these traits.

The present study aims at investigating the morpho-physiological responses of purslane plant to methyl jasmonate under salinity stress. As such it has conducted a split plot experiment, based on a completely-randomized design with two factors and three replications, in Medicinal Plants Research Center, Shahed University, Tehran, in 2017. The factors include salinity with four levels (0, 3, 6, and 9 dS/m) as main factors and methyl jasmonate with four levels (0, 0.25, 0.5, and 0.75 mM), the latter regarded as a sub-factor. Results show that by increasing salinity levels, the growth indices such as root length, fresh weight of root, chlorophyll b, total chlorophyll, and the amount of superoxide dismutase decline, while by increasing the salinity levels, the proline content and the activity of catalase and MDA in the leaf rise. Applying methyl jasmonate under salinity stress reduces not only the growth indices but also the photosynthetic pigments. The highest number of branches, number of leaves, and chlorophyll b have been obtained at a salinity of 6 dS/m with 0.5 mM methyl jasmonate. By raising methyl jasmonate level, the proline content and the activity of CAT increases, while the amount of MDA and SOD enzymes decreases. Therefore, it can be concluded that the tolerance of Portulaca oleracea plant to salinity is up to 6 dS/m, and that the consumption of low amounts of methyl jasmonate can improve yield and physiological indices in purslane. [ABSTRACT FROM AUTHOR]

To study the effect of different irrigation regimes on morphological and physiological characteristics of soybean cultivars, this experiment was conducted at Moghan Agricultural Research Center during 2009-2010 in Iran. The experiment was split plot based on randomized complete block design, with 3 replications. The main plots consisted of four irrigation regimes: I1, I2, I3 and I4 indicating irrigation after 60, 100, 140 and 180 mm evaporation from class A pan respectively and 3 soybean cultivars named Linford, L17 and Williams assigned in the sub plots. Results of combined analysis showed that with increasing irrigation intervals from I1 to I4 reduced growth period, plant height and leaf area index (LAI), number of nodes, branches and internodes significantly. Physiologic characteristics such as chlorophyll contain of leaves and relative water content (RWC) were also affected by irrigation regimes. LAI in I1 was 4.94 reduced inI4to 3.70.Plant height of soybean cultivars were declined by 21% in I4 (irrigation after 180 mm evaporation) as compared to I1 (irrigation after 60 mm evaporation). Soluble proline content of the leaves and electric conduction (EC) on the other hand increases significantly. There was significant differences among cultivars concerning the vegetative and physiological characteristics. Willams and L17 cultivars produced the highest numbers of nodes (15.5) and internode length (4.95cm) receptivity. The maximum proline content (65.6 µmol/F.W) and relative water content (67.65%) belonged to Linford cultivar. Interaction of irrigation regimes and cultivars was significant on plant hieght, LAI and proline content. Linford cultivar had more soluble proline under water limited condition and maintained higher LAI and plant height in I4 treatment as compared other treatments.

شوری آب و خاک یکی از مشکلات جدی و رو به توسعه در سطح جهان است، که سطح وسیعی از اراضی کشور نیز با این مشکل مواجه هستند. کاربرد میکروارگانیسم‌‌های اندوفیت که از مهمترین میکروارگانیسم‌‌های خاک محسوب می‌شوند، در کاهش تنش‌‌‌­های محیطی مانند شوری، به یک راهکار جهانی تبدیل شده است. بنابراین به منظوربررسی اثرات تلقیح قارچ اندوفیت Piriformospora indica و ریزوباکتریهای افزاینده رشد گیاه .Azospirillum sp بر رشد و خصوصیات فیزیولوژیکی گیاه گندم تحت تنش شوری، آزمایشی به صورت فاکتوریل در قالب طرح بلوک‌­های کامل تصادفی با سه تکرار در پاییز سال 1389 در گلخانه تحقیقاتی دانشکده کشاورزی دانشگاه ایلام اجرا گردید. تیمارهای آزمایشی شامل کاربرد پنج سطح میکروارگانیسم‌­های اندوفیت (قارچ پیریفورموسپورا ایندیکا، باکتری آزوسپیریلوم سویه‌های سازگار به مناطق شور و غیر شور، تلقیح توأم قارچ و باکتری و شاهد) و چهار سطح شوری آب آبیاری (2/0، 4، 8 و 12 دسی زیمنس بر متر) بود. نتایج نشان داد که قارچ پیریفورموسپورا ایندیکا تأثیر مثبت و معنی‌­داری بر رشد، میزان زیتوده تر و خشک اندام‌های هوایی، کلروفیل و محلول‌های اسمولیت در گیاهان گندم تلقیح شده تحت شرایط شور و غیر شور داشت، به طوری که کاربرد قارچ منجر به کاهش اثرات سوء شوری و بهبود رشد گیاه گندم گردید. گیاهان گندم تلقیح شده با باکتریهای آزوسپیریلوم از میزان زیتوده، تجمع اسمولیت‌­ها و کلروفیل بیشتری برخوردار بودند. تلقیح با باکتری آزوسپیریلوم سویه سازگار به شوری تأثیر مطلوب‌تری بر کلروفیل و میزان زیتوده داشت. نتایج این تحقیق نشان داد که تحت شرایط شوری می‌­توان از میکروارگانیسم‌­های اندوفیت در جهت افزایش رشد و عملکرد گیاه گندم استفاده نمود.