نشریه فیزیولوژی گیاهان زراعی
پیاپی 36 (زمستان 1396)

In order to investigate the effect of irrigation cut, bio fertilizers and foliar application of iron on yield and some morph physiological traits of barley, a factorial experiment was conducted based on randomized complete blocks design with three replications in 2015. Factors investigated included irrigation levels in three levels (full irrigation as control, moderate water limitation or irrigation cut at heading stage, severe water limitation or irrigation cut at boot stage (, bio fertilizers in four levels (no bio fertilizers, application of mycorrhiza, Azosprillium, both application Azosprillium and mycorrhiza) and foliar application of nano iron oxide in four levels (zero, 0.3, 0.6 and 0.9 gram per liter). The results showed that yield, yield components and chlorophyll content were decreased in irrigation cut at heading and booting stages. Maximum of grain filling rate (0.00236 gram per day), maximum of grain weight (0.065 gram), grain filling period (42.5 days), chlorophyll a and carotenoid (2.52 and 0.96 milligram per gram in fresh weight, respectively) were observed in both application conditions of Azosprillium and mycorrhiza, foliar application of 0.9 gram per liter nano iron oxide and full irrigation. The least amount of these traits were obtained in conditions of severe water limitation, no application of nano iron oxide and no foliar application. The results showed in the case of irrigation cut at the booting and heading stages, reduced the grain yield by 22.06 and 30.11 percent, respectively, in compared with full irrigation. The combined use of mycorrhiza and Azospirilium in comparison with the absence of application of them was 8.96 percent and foliar application by 0.9 gram per liter of nono iron oxide compared with 4.63 percent without foliar application had more seed yield. Therefore, it seems that the combined application of bio fertilizers and nano iron oxide can be proposed as barely tension modifiers under the conditions of water limitation.

In order to investigate of effect of salinity on ions accumulation in salt sensitive (IR29) and salt tolerant (FL485) rice genotypes, a factorial experiment based on completely randomized design with three replication was carried out in Karaj Biotechnology Research Institute in 2014. Seedlings of salt sensitive and salt tolerant were grown in Youshida nutrient solution culture and after 28 days, they were treated with two concentrations of zero and 100 milli Molar sodium chloride. Samples were collected from flag leaf, stem and panicles of each plant separately at zero, 7. 14, 21 and 28 days after applying the treatment and the concentration of sodium, potassium, chlorine, calcium and magnesium elements in each of the organs was measured individually. Result showed that under tension, the percentage of increase in sodium accumulation in flag leaf, cluster and stem of sensitive cultivar was 139, 71 and 121 percent than the control treatment and more than tolerant cultivar. Significant decrease was observed in potassium concentration of flag leaf, stem and panicles in both cultivars under salinity conditions. Salinity caused significant chlorine accumulation in flag leaf and stem of sensitive cultivar by the amount of 53 and 111 percent compared to control treatment. Significant decrease was observed in the concentration of chlorine in different tolerant cultivar organs, with the exception of stem in tension conditions. Under tension conditions, calcium accumulation in different parts of the tolerant cultivar was significantly more than sensitive cultivar. Upon application of saline treatment, the concentration of magnesium in leaf and leaf pods of both cultivars significantly decreased, while no significant changes were observed in panicle magnesium concentration of the two cultivars. Salinity caused a significant reduction in yield (48.4 percent) and grain yield components in sensitive cultivar, while the percentage of yield loss in the tolerant cultivar was not significant. The results showed that the FL485 genotype has the mechanism of reducing the rate of sodium and chlorine transfer to active parts of the plant, such as young leaves and panicles, thus prevents damage to these organs and prevents the significant reduction of yield.

Identifying the traits that can be considered in breeding programs for improving barley yield under rain fed conditions will increase the chance of success in breeding programs and will allow for planning to select effective traits for improving yield. In this research, in order to investigate the relationship between the yield and the important agronomic traits of barley under rain fed and laboratory conditions, in Iranian and European cultivars, 20 cultivars of Iranian barely and 24 cultivars of European barely were cultivated in a randomized complete blocks design with three replications at the experimental farm of the Agricultural Faculty of Razi University during 2014-15. Correlation analysis revealed that grain yield had positive and significant correlation with biological yield, number of fertile tiller per square meter, plant height, straw yield, harvest index and hector liter weight. The malt efficiency trait was positively and significantly correlated with grain width, rake length, one-thousand grain weight, number of seeds per spike, hectoliter weight, grain filling period, grain filling rate and day to physiological maturity traits. The path analysis showed that the most direct effect on yield was belonged to the number of fertile tillers per square meter. Grain filling speed had the most direct and positive effects on one-thousand seed weight and straw yield, had the most direct positive effect on biological yield. Ten factors were identified by factor analysis, the most important of which were the phonological factors affecting the target, the characteristics of the spike and flag leaf, and in total 78.33 percent of the total variation of the data was justified. According to the obtained results, in order to produce barley genotypes with high grain yield in rain fed conditions, it is proposed that plants with more fertile tiller numbers per unit area, higher biological yield, shorter phonological time and taller be selected.

Unfavorable environmental conditions cause tension in plants and impairment in the development and survival of plants. Water deficit is one of the most important environmental factors limiting the cultivation of almond under rain fed conditions of Guilan province. The foliar application of plants growth regulators, such as ascorbic acid and methanol due to physiological and morphological effects improve plant tolerance to unfavorable environmental conditions. The present factorial experiment was conducted in a randomized complete blocks design with three replications in two locations north of Iran (Astaneh Ashrafiyeh and Kiashahr) in 2015 cropping year. Two factors investigated including methanol foliar application at four levels of zero (control), 7, 14, and 21 volumetric percentage and four levels of ascorbic acid foliar application at zero (control), 250, 500, and 750 milligram per liter were considered. Foliar application spraying started during code stage 73 (pod growth) and it was repeated 15 days later. The results showed the simple effects of methanol and ascorbic acid foliar applications on measured pod yield, mature pod number per plant, shelling percentage, one-hundred seed weight, immature pod number per plant, plant height, seed protein and seed oil traits were positive and significant. The results of the experiment showed that foliar application of growth regulators increased peanut yield under rain fed conditions by improving the seed yield components. The maximum amount on pod yield, mature pod number per plant and shelling percentage traits were observed by two foliar application treatments of methanol (14 and 21 volumetric percentage) and two ascorbic acid treatments (500 and 750 milligram per liter). Therefore, it can be concluded that in the conditions of peanut rain fed cultivation, the use of methanol and ascorbic acid can improve grain yield and yield components.

In order to evaluate the drought tolerance of wheat cultivars and identification of tolerant and sensitive genotypes based on sensitivity and tension tolerance indices, a research was carried out under two conditions of water and drought tension in the form of a simple lattice design of 7 in 7 (including 7 incomplete blocks) and with 2 replications for 49 wheat genotypes including 45 double haploid lines of wheat (double haploid) with parents and two local cultivars (Gascogen and Pishtaz) as control in Shahrood in 2015-16 cropping year. The results of correlation between drought tolerance indices and grain yield under tension and non-tension conditions showed that there was a positive and significant correlation between Mean Productivity (MP), Harmonic Mean (HM), Geometric Mean Productivity (GMP) indices and Stress Tolerance Index (STI) with grain yield in both environmental conditions and were identified as suitable indicators for selecting high yielding cultivars in both tension and non-tension conditions. Among these indicators, the STI index was determined as the best indicator. The maximum amount of the above indices also belonged to the double haploid line 43 (DH43). Main components analysis based on seven indices of drought tolerance and grain yield in two conditions without tension and tension showed that the main component of the first, 68.15 percent and the main component of the second, 31.39 percent justify the variation of the initial data and thus, these two main components described a total of 99.5 5 percent of the total variation. By plotting the bi plot chart, it was determined that DH43, DH22, DH89, DH19 and DH13 double haploid lines were the most tolerant lines to drought tension among genotypes studied. The results of cluster analysis also corresponded to the results of the analysis of the principle components and the bi plot charts.

In order to evaluate the effect of salinity on agronomic and biochemical traits of rice cultivars, a two-year split plot experiment was conducted in a randomized complete blocks design with three replications in west area of Guilan, Astara, during the growing seasons of 2010-11 and 2011-12. In the present experiment, rice cultivars (Dorfak, Tabesh, Amol 3, Gharbi Siyah, Hassan Sarai Atashgah, Tarom Pakotah, Dom Sepid, Tarom Amiri, Hashemi and IR 29) were considered as subplot and salinity (cultivation in saline soil and culture in normal soil) as the main plot. The results of the experiment showed that salinity reduced the leaf soluble sugar, chlorophyll a and total chlorophyll content in all cultivars and the highest total chlorophyll content was obtained from Tarom Pakhotah cultivar under salinity tension conditions. The salinity increased the Peroxidase and Super Oxide Dismutase enzymes activity in all cultivars in each two years of experiment compared to normal conditions and Gharib Siyah cultivar had the highest and Hashemi cultivar had the lowest enzyme activity. There was a significant difference between the cultivars of rice in terms of number of tillers, number of seeds per panicle, one-thousand seed weight and biological yield under both salinity tension and normal conditions. Also, salinity reduced grain yield in all cultivars from 32.3 to 72.2 percent. The highest decrease in Tabesh cultivar and the lowest decrease in Hashemi cultivar was observed. The highest grain yield was obtained from Gharib Siyah cultivar under normal conditions and from Hashemi cultivar under salinity tension conditions. According to the obtained results for rice cultivation in situations where there is a possibility of salinity tension, Hashemi cultivar is more tolerant than other cultivars and it is recommended. But to grow under normal conditions (without salinity tension), cultivating Gharib Siyahi cultivar is recommended.

Salicylic Acid is a plant growth regulator involved in regulating physiological processes and plant response to adverse biological conditions such as salinity. Meanwhile, salinity is a major constraint for food production. Due to the detoxification of superoxide radicals produced as a result of salinity, salicylic acid plays an important role in preventing oxidative damages to plants. In the present research the effect of salicylic acid different concentrations, salinity and interaction effects of salicylic acid and salinity on morphological and biochemical parameters in barley was studied. Salinity concentration of zero, 25, 50, 75 and 100 milliMoar and salicylic acid concentration of zero, 0.5, 1 and 1.5 milliMolar were used in a completly randomized design as factorial in 2015.The results of this research showed that salinity reduced shoot and root growth, fresh weight and dry weight of shoots and roots, as well as reduction of chlorophyll and carotenoid; while in salicylic acid pre-treated plants, the amount of this reduction has been adjusted.On the other hand, increasing the amount of anthocyanins, chlorophylls and carotenoids indicates the role of consumption of one and one milliMolar salicylic acid in increasing the tolerance of this plant to salt tension. By examining the above, it can be concluded that the application of salicylic acid increases the tolerance of the plant to counteract the tension of salinity.

In order to evaluate the effect of different irrigation methods on agro physiological traits of grain corn cultivars, a split plot experiment based on randomized complete blocks design with three replications was conducted at the research farm Islamic Azad University of Ahvaz Branch during 2014-15 and 2015-16 cropping years. The main factor consisted of four different irrigation regimes and a sub factor including Single Cross 704, Single Cross 701 (Karoon) Single Cross 616 (Mobin). The obtained results of variance analysis showed that the effect of different irrigation regimes and genotype on seed yield and yield components, biological and economic of water use efficiency, chlorophyll a and chlorophyll b were significant in spring and summer planting season. Comparison of spring and summer planting showed a significant superiority of summer planting in the all measured traits. The superiority of Single Cross 704 compared to other hybrids in the agro physiological traits can be attributed to higher yield potential, early maturity and more adaptation to environmental conditions. The results of the mean comparison indicated that the I2 treatment (alternate furrow irrigation along the stages of 4 to 12 leaf and 12 leaf till the emergence of silk and conventional irrigation along the emergence of silk till to ripening) had minimum seed yield and yield components, chlorophyll a and b content and water use efficiency (both economic and biological) and allocated the highest percentage reduction in the measured traits than to I1 treatment (conventional irrigation in all growth stages). Therefore, deficit irrigation in the early and middle growth stages (four leaves until the silk emergence) is not recommended. Comparison of the I3 and I4 treatments indicated that the alternate furrow irrigation in the 12 leaf stage until the silk emergence (I3 treatment) led to the lowest reduction in seed yield and yield components than to conventional irrigation treatment (I1). In the other words, deficit irrigation in the middle stage of growth (12 leaf till to silk emergence) and conventional irrigation in the 4 to 12 leaf stage and the silk emergence until ripening to manage water availability limitation is recommended.