CROP PRODUCTION IN ENVIRONMENTAL STRESS
Year:2012 | Volume:3 | Issue:3-4 (SERIAL 7)|Papers Count:7

One of the main aims in plant breeding programs is achieving the high yielding and sustainable cultivars in different environments. For this reason, overall uniform experiments were carried out in semi-warm regions of the Khazar costs (Gorgan, Gonbad, Moghan and Sari) to compare 20 advanced genotypes of spring wheat as randomized complete block design with three replications and two growing years (2005-2006 and 2006-2007). In all four stations, to determine the high yielding genotypes, grain yield was measured and resulted data were subjected to analysis after uniformity test. According to the results of simple analysis of variance in different regions, grain yield of genotypes in all regions except for the Gorgan experiment in 2006 and Moghan 2006 showed significant differences. Results of the compound analysis of variance for the grain yield in all genotypes, years and places assuming the similarity of the effects of genotypes and being accidental effects of the years and places using the expected value showed that there is significant effect between the genotypes but interaction effects of place × genotype and year × place× genotype were significant. To evaluate the sustainability of genotypes, different parametric and nonparametric methods were used. Based on the results of the different methods that often led to the same results, 9, 10 and 16 genotypes had the higher sustainability but in some methods, results were different.Eventually, using the different methods, sustainability of 5 genotype (ATRAK/WANG-SHUI-BAI) according to its higher yield and sustainability, was selected as high yielding and sustainable genotype. This genotype is now grown in the semi-warm regions of the Khazar costs.

This experiment was carried out in split- split plot using randomized complete block design with three replications at research field of agriculture-jahad in semnan, Iran at 2010. The main factor were three levels of irrigation (irrigation is complet, disconnect the water at flowering and seed filling stages) in main plots and using cycocel in three levels (0, 1500 and 3000 ppm) in the sub plots, and zinc sulfate foliar application also in three levels (0, 3 and 5 per thousand) as sub plots. The result s showed that, drought stress from disconnects the water significantly affected at yield and yield components and RWC. Drought stress decresed grain yield, plant hight, and shoot dry weight, number of grain rows, number grain in row, 100 grain weight, and (RWC) and increased, root dry weight. Full irrigation had best yield, 25%better than mild stress, and 30% from hard stress. In water stress condition in flounce of cycocel and Zn spraying on grain yield and its components was positive so increasing the concentration of cycocel taking and Zn spraying improve the yield and yield components in stress condition, but not equally with control (full irrigation). The triple interaction was not significant on yield its components. Based on the results of simple correlation coefficient, there were appositive significant correlation between grain yield and number of grain in rows, 100 grain Wight and minimal correlation on interactive effect was between grain yield and plant height (0.193).

For evaluation effect of priming with phytohormones and utilization phosphorus solubilizing bacteria under drought stress on maize growth in stress phosphate condition on germination, yield and its components in poor soil of phosphate (7 ppm), was determined in two experiment, one of the in laboratory in carried out completely randomized design and another in field on the split split plot in carried out completely randomized block design using three replications in Fars province of Iran, 2011. Treatments in field consisted of: cut of irrigation in main plots in three level: control (without stress), cut of irrigation in end of vegetative growth stage (silking (R1)) and cut of irrigation in middle of reproductive growth stage (blistering (R2)), utilization phosphorus solubilizing bacteria in sub plots in three level: control (noneutilization bacteria), utilization bacteria sole and utilization bacteria in addition to half of recommendation doze of phosphate fertilizer in soil test and application priming in sub sub plots, in four level: control (dry seed), GA3 (20ppm), Auxin (5ppm) and distilled water for 12 hours of soaking. Results showed that was significant difference between plant growth regulators on percentage of germination. So that priming with water and GA3 improved percentage of germination with regard to control 27.5%. Just as priming with auxin increased percentage of germination 18.3%. In seedling vigor index, was not significant difference between hydro priming treatment and GA3 priming treatment but in compared to control treatment, increased 2.07 and 1.385 equal respectively. In interaction cut of irrigation and priming observed that each three priming treatment with regard to control (seed dry), increased significant 1000 kernel weight, kernel number per ear, RWC, percentage of leaf phosphate, grain yield and biological yield. Cut of irrigationR1 stage, decreased significant all of traits. In interaction cut of irrigation and utilization bacteria, in all of traits maximum mount was related to without stress and utilization bacteria in addition to half of recommendation doze of phosphate fertilizer in soil test and in all of traits use of bacteria decreased negative effect of cut of irrigation.

This experiment was conducted on research station farm of Mehregan in kermanshah province using RCBD design with 3 replications and 3 treatments including (irrigation by 7 days interval) versus (irrigation by 10 and 14 days intervals) on corn single cross (704) in 2006. Drought stress was exposed from flowering stage.The results showed that there were direct significant correlations between the number of grain pre ear with grain yield pre plot at 1% and ear length, stem diameter and internode with grain yield pre plot at 5% levels in normal condition. There were also direct significant correlations between the number of grain pre ear and ear length with grain yield pre plot at 1% and internode with grain yield pre plot at 5% levels in ten days irrigation interval. There were direct significant correlations between internode, plant height, stem diameter and the number of grain pre ear with grain yield pre plot at 1% level in 14 days irrigation interval. Stepwise regression results showed two traits (number of grain pre ear and plant height) in 7 days irrigation interval and one trait (ear length) in 10 days irrigation interval and so the number of grain pre ear, one thousand grain weight, stem diameter in 14 days irrigation interval were inserted to regression model. In path analysis on the most important traits on grain yield pre plot, the number of grain pre ear, one thousand grain weight in normal condition and ear length, internode in ten days irrigation interval and the number of grain pre ear, one thousand grain weight in 14 days irrigation interval had the most direct effects on dependent variable. It can be concluded in the normal condition the vegetative traits such as stem thickness, internode and some of yield components such as the number of grain pre ear and length ear and so in the stress condition length ear, number and weight of grain are effective on grain yield generally.

In order to determination effect of different nitrogen application rates and splitting methods on quantities and qualities yield of canola, a field experiment was conducted as split-plot using a randomized complete block design with four replicates at Jouybar (Iran) in 2008-9. Three rates of nitrogen fertilizer including (0, 100 and 200 kg N ha–1) as main plot and three nitrogen splitting in sowing time and stem elongation (bolting begins), first flower opens and flowering ends as sub plot. Results indicated that there were affected grain yield, biological yield, oil yield and oil content at 1 % probability level by nitrogen rates and splitting and only oil yield at 5 % probability level by nitrogen rates. High nitrogen application had increased all traits exception oil content duo to decreasing. The highest pod number, grain yield, biological yield, oil yield and oil content had showed in T2 and lowest was obtained in T3. Oil yield with 100 and 200 kg/ha N application in comparison with check had increased about 53 and 49 %, respectively. The highest grain yield and oil yield was obtained under interaction of N200T2 and lowest under interaction of N100T3. Finally, T2 with accompanying increase nitrogen was the best treatment.

In order to study the effects of different day interval and density of methanol spraying on grain yield of soybean (cv. Williams) an experiment were conducted in form of split plots in base of randomized complete blok desin with four replications in field research of Azad University of Karaj, Mahdasht (35 degree and 45 minutes of north latitude and 51 degree and 6 minutes of east longitude with 1313 height from soa level).Seeds were disseminated on the ordibehesht 28th (in may of 2010) and in the depth of 5 cm. Experimental factors were include of foliar spraying distances in five level of days interval (10, 15, 20, 25, 30) and four level of methanol density in base of volume percentage (0, 15, 20, 25). In all of treatments for avoid of poisonous methanol effects in sunshine appearance, we applied Glycine rate of 2g per liter. The spraying was carried out at 17 to 20 Pm each time. The results showed that there where significant differences at the probability level of 1% (p<1%) between the frequency of spraying and the production of soybean and its components and on the other hand between the spraying amount of Methanol and the production of soya bean and its components. The best production of the bean was related to the treatment F20M25 with the amount of 3244.6 kg per hectare.

The aim of this research was to determine the effect of cold stress levels on growing period, yield and some yield components of 15-bread wheat (Triticum aestivum. L) cultivar grown Azerbaijan in Iran. Experiment was carried out in split plot on randomized complete block design with tree replications in two years 2009-2010. Tree levels of cold stress were planted with the first of 22 October and the others followed by 30 days intervals.15 cultivar (five genotypes with types winters names Sayson, Martin, Gaskogen, C-82-12, C-81-14, 5 genotype with type intermediate including Alvand, Mahdavi, Zarrin, Marvdasht, Tous and five genotypes with type spring names Shiraz, Pishtaz, M-79-7, M-81-13 and Kavir) were the sub plot and cold stress level were the main plot. According to the results of two years. Cold stress had a significant effect on grain number per spike, plant high, 1000- kernel weight (1000-KW) and grain yield. Grain yield obtained from the first cold stress level, consequently the period of first cold stress level planting time and growth condition on the first cold stress treatment level was suitable for tillering that the variety have enough time to tiller their tolerance to cold stress and could be concluded as optimum sowing period for maximum grain yield for the region.