CROP PRODUCTION IN ENVIRONMENTAL STRESS
Year:2012 | Volume:4 | Issue:2 (SERIAL 9)|Papers Count:6

To study the effect of water stress and the application of growth regulator (cycocel) and Zinc spray on the protein rate, the major elements and some physical characteristics in corn (hybrid Ns540) .A split-split plot experimental with three replications in a randomized complete block design in Semnan Agricultural Research Station in 2010 in was run. The main factor included three levels of irrigation (irrigation complete, disconnect the water at 71 BBCH and 61 BBCH) in main plots and taking cycocel three levels (without taking cycocel consumption cycocel 1500, and 3000 parts per million) in the subplots and spraying zinc sulfate in three levels (no foliar applications, foliar applications of zinc sulfate at 3 and 5kg per thousands) as the subplots - are considered minor. Analysis of variance showed that the impact of cut irrigation on protein content, major elements such as phosphorus, potash, zinc, copper and iron, and water use efficiency is significantly. With the increased tension of the grain protein content and concentration of phosphorus, potash, zinc, iron and copper were reduced and increased water use efficiency. That results showed, taking cycocel, potash and phosphor decreased and other indicators increased. Zinc spraying the exception of the iron (Fe) increase in other indicators. the Correlation between Important elements and components of protein content and water use efficiency showed that Positive and significant correlation between water use efficiency and a high copper content of 0.474 percent is established And grain protein correlated with leaf phosphorus content of 0.522 percent. The findings can be to corn-growing of Semnan and similar region drought conditions that prohibit the use of certain materials and components that manufacturers offer to achieve good economic performance and quality.

One of availability ways to reach to sustainable agriculture, use of some microorganisms that have important role in supplying food requirement that can refer to mycorrhiza. This research is investigating the effect of mycorrhiza and vermicompost as the biologic fertilizers to compare with chemical fertilizer phosphor and nitrogen on yield and yield component of corn based on factorial in a randomized complete blocks design with 3 replication in soil control condition was done in 2010. Treatment include: Using chemical fertilizer (F) in three levels of fertilizer's urea, p2o5 and k2o include: F0 (nitrogen 0, phosphurus 0, potassium 0), F1 (nitrogen 70, phosphurus 50, potassium 30) and F2 (nitrogen 150, phosphurus 100 and potassium 50) kg/ha, vermicompost treatment in two levels (using V1 and non-using V0) and Mycorrhiza treatment in two levels (using M1 and non-using M0) (population 105 g/spore). Results of variance analysis showed there was significant difference between different levels’ interaction of vermicompost, chemical fertilizer and mycorrhiza on length root, dry weight of seedling and seedling vigor. Treatment comparing showed that in three traits of length root, dry weight of seedling and seedling vigor, treatment F1V1M1 with average 5958.3cm, 17.633g and 129.67g respectively were the highest and increased 18.3, 18.1 and 72.8% respectively with regard to control treatment (F0V0M0).

In order to investigate the effect water stress on four cultivar of rapeseeds (Brassica napus L.), we did an experiment in research field of agriculture faculty of shahed university as split plot with use of randomized complete block design with three replications. The whole factor was including of three level of irrigation (5, 10 and 15 days orderly) and sub-factor was four cultivars of autumnal rape seed (RGS, Okapi, Elite and Tallaie). Length plant, length inflorescence, leaf soggy weight, leaf arid weight, stem soggy weight, stem arid weight, leaf area index, pod per plant, 1000-grain weight, percent oil and protein was measured. Variance analysis of data showed that effect of irrigation treatments was significant (P=0.05) on leaf arid weight and effect of varieties treatments was significant (P=0.01) on length inflorescence, pod per plant and leaf area index (P=0.05); but interaction effect of irrigation and varieties was significant (P=0.01) on length inflorescence only. Means comparison showed that Elite variety has the highest length plant (100.16 cm) then Okapi, RGS and Tallaie. Elite variety was superior than other varieties from length inflorescence (44.10 cm) followed by Tallaie, Okapi and RGS, respectively. Also, Elite variety was superior than other varieties from pod per plant (24.65) followed by Okapi, RGS and Tallaie, respectively. Stem soggy weight indicated more correlation (r=0.867) with seed oil percent than other yield component. Also these varieties weren't significantly different (P=0.05) in seed oil percent.

This experiment was conducted on fourteen genotypes from two and three maturity group of soybean as Baj-Maj, M9, Hy-1, L17, Union, Bonus, Williams,Hack, Clark, Halcor, Flanklin, LD9, Steel, Elgine under two normal and drought stress condition. The stress was induced from flowering stage as 7 versus 14 days irrigation. The results showed significant correlation between one hundred grain weight, inter nod, plant height with grain yield at 1% level under normal condition. The highest correlation belonged to plant height and inter nod. There were positive and significant correlation between plant height and number of grain per plant and one hundred grain weight at 1% level too. On the other hand the positive and highest significant correlations were between plant height, days to maturity, inter nod with grain yield under drought stress at 1% level. There were positive and significant correlations between plant height and other studied traits such as inter nod, number of pods per plant, number of grain per plant, average leaf area, one hundred grain weight and grain yield at 1% level. In step wise regression analysis under normal condition, four traits including plant height, average leaf area, number of sub branches and number of pods per plant were inserted to statistical model. They supported 69.6% of variation of dependent variable. In path analysis the highest direct and final effect on grain yield belonged to plant height. The results of step wise regression analysis under drought stress, three traits including plant height, days to maturity and one hundred grain weight were inserted to statistical model. They supported 64.1% of variation of dependent variable. In path analysis the highest direct and final effect on grain yield belonged to plant height.

Overlapping the Faba bean harvesting time with rice transplanting in paddy fields is one of the limiting factors in planting faba bean. To decrease growth duration of faba bean and early harvesting of it, this research work was conducted in paddy fields of Rice Research Institute of Iran in Rasht during 2009-2010 growing season. The experiment was carried out on a randomized complete block design with three replications Experimental treatments included planting date in 3 levels of 1, 16 and 31 October, and concentration of paraquat in 4 levels of 0, 0.2, 0.4 and 0.6 Kg/ha active ingredients. Desiccant application used at 60% of grain moisture of pods in 1/3 base of plant. Based on the results of analysis of variance, main effects of desiccant usage and planting date were significant in most traits. The interaction effects of planting date and desiccant application were significant for biological yield, grain filling time and maturity time. The control treatment with average of 233 days and application of 0.6 Kg/ha paraquat with average of 225 days had maximum and minimum growth duration, respectively. Maximum grain yield and protein yield were obtained in 16 October (7204 and 2031.3 kg/ha respectively). Results showed that usage of 0.6 kg/ha paraquat in 31 October, produced minimum grain yield with average of 3996 kg/ha due to reduced grain filling time and 100-grain weight.

In order to study the effect of heat stress on yield and physiological characteristics of sweet corn varieties, an experimental was conducted in Jiroft Agricultural Education Center during 2011-2012 years. The experimental design was planned out in split plot based on randomized complete block design with 3 replications. The main factor was heat stress in three levels and the sub factor was including three sweet corn cultivars namely Chase, Temptation and Obsession. For exposure heat stress the sweet corn cultivars were grown in three planting date in field, 20 February (normal planting), 10 March (late planting) and 25 March (very late planting). The results showed that with increasing heat stress the ear length and diameter, number of grain per row, number of row per ear, total grain per ear decreased but no fertilization percentage increased. Heat stress affected the ear yield through the increasing percent of no fertilization and finally decreasing number of total grain per ear, however highest ear yield (13360 kg/ha) was recorded in normal planting date and the lowest ear yield was obtained from late and very late planting date by 6606 and 7517 kg/ha, respectively. There was no significant difference between late and very late planting date. The cultivars had significant difference on ear length and diameter, cob diameter, number of grain per row, number of row per ear, total grain per ear, 1000 seed weight, no fertilization percentage and ear yield. Highest and lowest ear yield was obtained from Obsession and Chase cultivars by 10230 and 8378 kg/h, respectively.