JOURNAL OF CROP PRODUCTION RESEARCH (ENVIRONMENTAL STRESSES IN PLANT SCIENCES)
Year:2010 | Volume:1 | Issue:2|Papers Count:8

Water deficit stress effect at pod development stage was evaluated on eight soybean cultivars and lines tolerance. The results showed that potential yield had significant and positive correlation with, tolerance; stress tolerance index, mean productivity and geometric mean productivity there were significant and positive correlation between yield and tolerance index and geometric mean productivity in water deficit stress. Was significant M4 and M12 lines with 3269 and 1385 kg ha-1 had the highest and lowest yield in control condition, respectively. Under water deficit condition, Clark cultivar (1385 kg. ha-1) and SRF450 (801 kg. ha-1) produced the highest and lowest grain yield. M12 line had lower decrease in grain yield and M4 was the most susceptible among lines and cultivars. Mean yields of all cultivars and lines under normal and water deficit irrigation condition were 2512 and 1191 kg. ha-1 respectively. Stress intensity were 0.526, too. However, there were significant and positive correlation between yield in water deficit stress and control conditions with GMP and STI, It seems, they can be used for identifying water deficit tolerant soybean genotypes.

In order to Study the effect of salt stress on yield and yield components of winter rapeseed (Brassica napus L. ), and the most tolerant cultivars, an experiment carried out in factorial design in the basis of randomized complete blocks with 4 replications in 2008-2009. Experimental treatment were the combination of 4 cultivars (SLM046, Okapi, Licord and Elite) and salt stress conducted from sodium chloride in 6 levels (0, 75, 150, 200, 250 and 300 Mm). The variance analysis results showed that increase in salt stress had negative and significant effect on seed yield, 1000 seed weight, seed number in pod, pod number in plant, leaf area and plant height and increase in salt application reduced mentioned characters% 70.48, %58.71, %49.72, %75.15, %87, 76 and %50.33 in compare to normal condition alternatively and instead of leaf area in other cases observed significant differences between cultivars. SLM046 had the highest amounts of all characters. Seed yield mean comparison showed SLM046 and Elite were the most susceptible and tolerant cultivars.

In order to study the effects of water deficiency stress, different levels and split application of nitrogen on distribution of dry matter between different plant part and some morphological characteristics of grain corn SC.704 under Khuzestan climate conditions in two summers, 2004 and 2005, this research was conducted in University Natural Resources and Agricultural Science of Khuzestan based on three split-plot field experiments, using Randomize Complete Blok Design (RCBD). Each of the irrigation treatments implemented separately in each experiment have been as follows; Optimum irrigation, moderate drought stress and severe drought stress (irrigation after getting out 30, 40 and 50% of field capacity respectively). In each experiment three nitrogen levels consist of 140, 180 and 220 kg Nha-1 were applied in main plots and subplots which consisted of split application of nitrogen (S1=%50 at planting +50% at V6 stage, S2=25% at planting stage and+75% at V6 stage, S3 =%25 at planting +50% at V6 stage +25% at V12 stage). Results showed that dry weight of ear, cob, stem and leaf, plant height, ear length were reduced significantly in response to increasing to drought severity. These traits were increased in response to increasing the nitrogen application. Proper split application of nitrogen when the need of plant was height has positive effect on distribution of dry matter on plant shoots. The increase of nitrogen application especially in optimum irrigation and moderate drought stress caused increased dry weight of ear, stem and leaf. When available water decreased, positive effect of nitrogen application on these traits decreased significantly. Results showed that under severity drought stress the increase of nitrogen consumption in order to the reduction effect of severity drought is not recommended but S3 treatment recommended for all three irrigation condition.

In order to investigate the effects of  salinity on germination of common bean cultivars an experiment was conducted at the laboratory of the Islamic Azad University, Eghlid Branch in 2009. Effect of four salinity levels included 0, 1, 2 and 3 ds/m on seed germination percentage root and shoot length and K and Na accumulation in four common bean cultivars included Jules, daneshkadeh, Khomein and G14088 was studied. The experimental design was factorial based on completely randomized design with three replications. Result showed that salinity had significant effect on seed germination percentage. The highest and lowest germination percentage was observed in 0 and 3 ds/m respectively. Salinity reduced root and shoot length. Salinity caused Na accumulation in germinated seeds, but reduced amount of K. Jules cultivar had the maximum germination percentage and the lowest Na amount at 3 ds/m salinity treatment. According to measured traits, Jules and G14088 cultivars were the most resistant and sensitive to salinity, respectivly.

The objectives of this study were to evaluate the effects of limit irrigation on yield and yield components in wheat. The study was conducted using a split plot design in completely randomized blocks with four replication and 16 treatments. All farm experiments were conducted in agriculture research field of Azad University of Karaj in 2007 cropping season. The main plot treatments consisted of 8 irrigation regimes as control treatment (T1), irrigation in 60 and 80 depletion of soil moisture (T2 and T3), stop irrigation in stem elongation stage (T4), stop irrigation during stem elongation to ripening (T5), stop irrigation in flowering stage (T6), stop of irrigation during flowering to ripening (T7), stop irrigation in grain filling stage (T8) as first factor. The second plot as secondary factor consisted of two wheat cultivars (Chamran and Marvdasht). In this study, grain yield and yield related characteristics were evaluated and all treatments showed significant differences with control plot. The results of the study revealed that limited irrigation have a significant effect (p>0.001) on grain yield, biological yield, harvest index and 1000 grain weight. The treatments (T2 to T8) showed 15.7%, 37.8%, 13%, 61%, 45%, 62% and 43% grain yield reduction, respectively. Water stresses in flowering to ripening period (T7) have the most influence on grain yield. Also, statistical tests on yield data showed both varieties (Chamran and Marvdasht) similarly affected by water stress. Correlation coefficient tests showed that biological yield (r 2=0.77), 1000 grain weight (r2=0.74) and harvest index (r2=0.69) have the most correlation with grain yield.

In order to investigate the effects of different nitrogen and phosphorus levels on seed protein content and protein yield of mungbean variety Partow a field experiment was conducted at the Research Farm of the Islamic Azad University of Shahre-rey in Tehran, Iran in 2009. The Experiment was laid out with factorial arrangement in a Randomized Complete Block Design with three replications. Five levels of nitrogen (0, 30, 60, 90 and 120 kg N ha -1 ) and six levels of phosphorus (0, 30, 60, 90, 120 and 150 kg P2O5 ha -1 ) were the treatment variables. Results showed that application of N and P fertilizers significantly increased the seed protein content and protein yield. The maximum seed protein content (22.53%) and the highest protein yield (49.55 g m -2 ) were obtained when 120 kg N ha -1 and 150 kg P 2 O 5 ha -1 were applied.

In order to study the effect of drought stress (Limited irrigation) on different traits of Bean, fifteen red bean and white bean genotypes were planted in a randomized group balanced block design with three replications under normal and drought stress conditions and 24 traits were recorded. The results showed that among experimental factors, the most decrease in red bean belonged to plant yield and the most decrease in white bean had been in leaf and shoot dry weight and also 100-seed weight. The results of step wise regression showed that the 100-seed weight, number of seed per plant and days of cotyledon leaves appearance under drought stress condition had the most effect on the yield of red bean and the number of seeds per plant, 100-seed weight, leaf dry weight and shoot dry weight under drought stress condition had the most effect on yield of white bean. GMP, STI, and MP were the most suitable indices for selecting drought resistant genotypes. Based on the‎ indices KS-31146 and KS-31150 in red beans, and KS-41133 KS-41127, KS-41160 and KS-41165 in white beans, were found as resistant genotypes.

Four resistant advanced lines of wheat M-78-1, M-78-3, M-78-10 and M-78-16 and Bolani, as the susceptible variety, were intercrossed in a half diallel design. Seeds of parents and F1's were planted in pots with sterile soil in a Randomized Complete Block Design with three replications in greenhouse. Seedlings were inoculated by spores of 6E130A+ pathotype of yellow rust and latent period was measured. Analysis of variance by method of Griffing indicated significant difference among the lines for general and specific combining abilities. Results of Hayman method of analysis of variance showed no significant difference of Wr+Vr among the lines, whereas the difference of lines for Wr-Vr was significant. Coefficient of Wr/Vr regression was significantly different with zero but was not with unit. Dominant alleles were more frequent than recessive ones. Broad-sense and narrow-sense heritabilities were estimated 94% and 60%, respectively. Totally, the results of analyses demonstrated the importance of both additive and non-additive gene effects in genetic control of latent period.