نشریه فیزیولوژی گیاهان زراعی
پیاپی 34 (تابستان 1396)

Drought tension is one of the important factors influencing the yield and living conditions of most crops such as mung bean. Therefore, the investigation drought tolerance traits can help identify and select more tolerant cultivars. The present experiment was carried out as factorial in a completely randomized design with three replications, or at three levels of irrigation 40, 60 and 80 percent crop capacity and five cultivars and lines of Uzbek, Pareto, Hindi, A73-726 lines and B73-726 mung bean in greenhouse culture conditions. The results showed that drought had a significant effect at a probability level of one percent on pod number per plant, plant weight, number of main branches, leaf area, root dry weight and root diameter. With the increasing intensity of drought, the rate of photosynthesis, transpiration rate, photochemical quantum yield, relative water content of leaf, carotenoid, chlorophyll a and b, total chlorophyll content of leaves and the ratio of a to b chlorophyll decreased, while the amount of leaf proline increased significantly (p≤0/01). Also, there was a significant difference in these traits among the cultivars, a 73-726 line had a higher rate photosynthesis, the relative water content of leaf, carotenoid, proline, chlorophyll a and b, total chlorophyll content of leaf and the ratio of a to b chlorophyll than the other examined cultivars and lines in the present experiment.

In order to investigate the effect of seed priming with salicylic acid and water deficit tension on enzyme activity and yield of grain corn, the present experiment was conducted as split plot based on randomized completely blocks design with three replications at the Agricultural Research Station of Islamic Azad University, Tabriz Branch in 2015. The Main factor was consisted of two levels of normal irrigation (without tension) and water deficit application based on 70 and 110 millimeter evaporation from evaporation pan class A, respectively after from 8-9 leaf stage of corn and sub-factor consisted of three levels of corn seed priming with salicylic acid concentrations of 100 and 200 ppm with the control (no priming) in pre-planting stage. According to the results of the experiment, superoxide dismutase enzyme activity increased by 27 percent in maize leaf due to occurrence of water deficit tension and seed priming with salicylic acid concentrations of 100 and 200 ppm increased superoxide dismutase activity by 32 and 42 percent, respectively. Corn grain yield by applying water deficit tension with increasing water irrigation period from 70 to 110 mill meter evaporation from pan decreased as 110 grams per square meter from 8-9 leaf stage onwards, and seed priming with salicylic acid concentrations of 100 and 200 ppm increased corn grain yield up to an average of 13.50 percent and no significant difference was observed in the grain yield between two concentrations. Therefore, due to the lack of significant difference in terms of studied traits and especially grain yield between two levels of concentration, it seems that seed priming with 100 ppm salicylic acid concentration in order to increase corn grain yield in both cases, normal irrigation and water deficit tension have been effective.

Potato is cultivated as a spring plant in cold areas. The challenges facing potato cultivation are late spring frost, early autumn cold and summer heat in these areas. The present factorial experiment based on randomized complete blocks design with three replications was carried out in Gandoman region, Chaharmahal and Bakhtiari Province, Iran in 2014-15 cropping years. The first factor included three cultivars Jelli, Fontane and Burren and the second factor was the combination of different treatments of calcium and Jasmonic acid (with 5 micro Molar concentration) consisted of: 1- calcium Jasmonic acid before rhizome formation stage (T1), 2-calcium Jasmonic acid after rhizome formation stage (T2), 3- Jasmonic acid before rhizome formation stage(T3), 4- Jasmonic acid after rhizome formation stage (T4), 5- calcium from calcium nitrate source(T5), 6- control (without application of two factorsT6). According to the results, it can be deduced that Jasmonic acid and calcium reduced the undesirable effect of temperature tension in both stages before and after the rhizome formation. In addition, these positive effects were higher when Jasmonic acid and calcium were applied in combination and prior to the rhizome formation. According to the obtained results, both Jasmonic acid and calcium factors had a significant effect on the under investigation cultivars, so that Jelly cultivar had better reaction than other cultivars. Also, among all under investigation treatments, T1 treatment in all investigated traits except Malondialdehyde, showed the highest mean in all three examined cultivars. Totally, according to the obtained results, the application of combined Jasmonic acid and calcium treatment in the pre-rhizome stage, reduced the adverse effect of temperature and germicidal stimulation, resulted in higher yield.

To investigate the effect of planting pattern and plant density on some physiological and growth characteristics in corn single cross 704, a factorial experiment was conducted in a randomized complete blocks design in four replications in Islamic Azad University, Miandoab Branch. Different levels of treatments consisted of three levels of plant density (7, 9 and 11 plants per square meter) and two levels of planting pattern (one and double planting rows). The results of the present research showed that the highest grain yield with 14121 kilogram per hectare belonged to the density of 9 plants per square meter and planting pattern of double rows. The most number of ears per square meter was observed at the density of 11 plants per square meter which did not have a significant difference with the density of 9 plants per square meter. By increasing the density, one-thousand grain weight decreased; however, no significant difference was observed between densities of 7 and 9 plants per hectare. The highest number of seed per ear and ear length was obtained at 7 plants per square meter and two- rows tillage, which did not have significant difference with 9 plants per square density and two rows cultivations. The highest leaf area index and plant height belonged to the density of 11 plants per square meter and the two-row planting pattern. The highest and lowest chlorophyll index and remobilization percent were allocated to densities of 7 and 11 plants per square meter, respectively. The correlation coefficients between traits showed that the correlation between grain yield with grain number per ear, ear length, ear number, leaf area index and remobilization were positive and significant. According to the results of this research, the density of 9 plants per square meter and the two-row planting pattern for single cross 704 corn are recommended at Miandoab region.

The present research was conducted to determine the effect of Cytokinin and Gibberellin hormones on the improvement of germination traits of maize cultivars with different vigor. The experiment was conducted in the seed laboratory of the Agronomy and Plant Breeding Department of the Faculty of Agronomy and Animal Science of University of Tehran in 2015. The maize cultivars used included Hybrid Single Cross 704 cultivar and Hybrid Single Cross 260 Cultivar. Standard germination test was completely randomized performed to determine the voguers of two cultivars of corn. 704 cultivar showed higher germination indices than 260 cultivar. The seeds were then investigated in the form of factorial in a completely randomly design in a completely randomized design with four replications in order to create different vigorous under the pre-mature aging test at 5, 10 and 15 days and after the pre mature aging test of the effect of different concentrations of Cytokinin and Gibberellin hormone on decayed seeds of corn cultivars. In all experiments, the traits of germination percentage and rate, root length, shoot length, root fresh weight, stem fresh weight, root dry weight and shoot dry weight were measured. The obtained results showed that aging or seed deterioration, causes reduction in germination percentage and rate, root length, root fresh weight, stem fresh weight, root dry weight and shoot dry weight. Under pre mature aging treatments, the difference was significant between cultivars. In 704 cultivar, traits measured under pre mature aging treatments showed a lower reduction than 260 cultivar. The treatment of decayed seeds with Gibberellin and Cytokinin hormones improved the measured traits. The effect of higher concentrations of hormone in long-term aging treatments was very significant. Increasing the concentration of hormones from 50 micromoles to 150 micromoles improved the measured traits.

In order to investigate the effect of super absorbent polymer on yield and some biochemical charactristics of corn under low irrigation conditions, the present experiment was conducted in split plots arrangement in a randomized complete blocks design with three replications at a field of located in Andimesh city in 2015-16 cropping year. Treatments of the experiment included low irrigation in three levels included full furrow irrigation (control), furrow irrigation in the form of a fixed one in between, furrow irrigation in the form of a variable one in between as the main factor and super absorbent polymer in three levels included non use of superabsorbent (control), 100 kilogram per hectare super absorbant and 200 kilogram per hectare super absorbent as subfactorwere considered. The results showed that low irrigation had a significant effect on grain yield, number of grain per ear, one- thousand grain weight, proline and the amount of chlorophyll a and b. Also, the use of superabsorbent significantly increased grain yield, grain yield components, the amount of chlorophyll a and b and decreased proline content. In the investigation of the effect of low irrigation and superabsorbent interaction, the number of grains per ear and grain yield were significant at one percent probability level. The highest grain yield with an average of 6.6 ton per hectare was related to full irrigation and 200 kilogram per hectare superabsorbent which was not significantly different with furrows irrigation treatment in the form of a variable one in between conditions of 100 and 200 kilogram per hectare superabsorbent by 6.1 and 6.5 ton per hectare, respectively. The lowest grain yield obtained from fixed one in between furrow irrigation under conditions of no use of superabsorbent with 4.6 ton per hectare. In general, the results showed that superabsorbent polymers have a positive and significant effect on yield parameters due to the availability of water and nutrients in two conditions of full irrigation and low irrigation.

In order to investigate the effect of methanol foliar application and drought tension on growth indices of soybean, an experiment was conducted as split plots in a randomized complete blocks design with three replications in the research field of Faculty of Agriculture, Islamic Azad University of Karaj Branch in 2015. Drought tension included irrigation after 40, 60 and 70 percent available moisture evacuation as the main factor and methanol foliar application included no spraying (control), spraying with 7, 14 and 21 percent by methanol volume as the sub factor were considered. Spraying was carried out three times during the plant growth season and at intervals of 15 days on the aerial parts. The measured traits included: dry matter accumulation, grain yield, crop growth rate, relative growth rate, net assimilation rate, Proline, soluble sugars, Peroxide hydrogen and relative moisture content. The results showed that the effect of methanol foliar application in drought tension conditions, was significant on the relative increase of all growth indices and yield. The comparison of the average of the examined traits showed that methanol foliar application had a positive and significant effect on soybean growth indices which led to increasing dry matter and grain yield of soybean; as the highest grain yield was obtained during methanol foliar application with 21 percent volume. Moreover, under mild and severe tension conditions with application of the highest amount of methanol, the amount of peroxide hydrogen reached to the lowest level. According to the obtained results, with application of 14 percent methanol, more increase was observed in the efficiency of proline under severe tension conditions. Increasing the volume of methanol from 7 to 14 percent, the relative water content was preserved under tension conditions.

In order to investigate the effect of salicylic acid foliar application on morphological¡ physiological traits¡ yield and yield components of red bean under drought tension conditions¡ a field experiment was conducted as split plots based on randomized complete blocks design with three replications in Damavand region in 2014. Main plot consisted of irrigation regime at two levels optimal irrigation till the end of the growing season (based on 70 millimeter evaporation from evaporation pan class A) and drought tension at the flowering stage (based on 110 millimeter evaporation from evaporation pan class A) and sub plots included Salicylic acid foliar application at concentrations in four levels zero (pure water)¡ 0.1¡ 0.7 and 1.5 mill molar. The results showed that in drought tension conditions physiological traits¡ such as pigments photosynthetic¡ yield and yield components of beans decreased significantly. As¡ the water deficit tension reduced plant height¡ chlorophyll a¡ chlorophyll b¡ number of pods per plant and one-thousand grain weight and increased proline. Also¡ foliar applications of salicylic acid improved the total chlorophyll¡ proline and grain yield components. The interaction of irrigation regime and foliar applications of salicylic acid on chlorophyll a¡ chlorophyll b¡ total chlorophyll and grain yield was significant. Using 0.7 mill molar salicylic acid in optimum irrigation conditions increased 70 percent chlorophyll a¡ 60 percent chlorophyll b and 56 percent grain yield compared to non-application conditions of salicylic acid and drought tension. Using salicylic acid on bean plant traits in drought tension conditions in most cases had a positive effect. So that the concentration of 0.7 mill molar salicylic acid reduced the adverse effect of drought tension and increased tolerance of red bean crop.