CROP PRODUCTION IN ENVIRONMENTAL STRESS
Year:2012 | Volume:4 | Issue:1 (SERIAL 8)|Papers Count:6

In order to effects of salicylic acid and selenium on yield, yield component dry land wheat cultivars, a field experimental was carried out as factorial based on complete randomized block design with four replicates in the research station of Islamic Azad University- Arak Branch, Iran in 2010-2011 crop season. Experimental factors were including of salicylic acid in three levels, without salicylic acid, seed priming with solution of 0.5m mol salicylic acid and seed priming with solution of 0.5m mol salicylic acid along with sprayed at the rates of 1m mol two weeks before flowering, selenium without and with selenium and that applied at the rate of 18 g ha-1 and three dry land wheat cultivars including of Azar 2, Sardary and Rasad. Results showed maximum of remobilization rate, current photosynthesis, efficiency and current photosynthesis contribution and grain yield was obtained from Azar 2 cultivar. Current photosynthesis rate and grain yield in Azar 2 cultivar increased by 17, 23% and 19, 16% as compared with Sardary and Rasad cultivars respectively. Application of salicylic acid as seed priming was increased current photosynthesis rate, current photosynthesis efficiency and grain yield. Application along with salicylic acid as seed priming and foliar application of selenium increased grain yield by 9% as compared with control. Interaction effects three-way of showed that maximum current photosynthesis rate equal 1236.80 kg ha-1 and grain yield equal 1604.10 kg ha-1 was obtained from treatment of foliar application of selenium and without salicylic acid in Azar 2 cultivar. The present results showed that by using selenium and salicylic acid under dry land condition can obtain acceptable yield.

In order to estimate of row spacing and seed value on yield and yield components in Kohdasht cultivar wheat (Triticum aestivum. L.) an experiment was conducted in under dry land condition in research station. The experiment was arranged as randomized complete block design with three replicates. The experimental factors including of three row spacing (12, 17 and 25 cm) and four seeds value (250,  300, 350 and 400 seed per m2). Grain yield, spike per m2, kernel per spike, kernel per m2, kernel per spikelet, harvest index were significantly affected by different row spacing. And kernel yield, spike per m2, kernel per spike, kernel per m2 ,spikelet per spike, kernel per spikelet, biological yield and straw yield were significantly affected by different seed value. And kernel per spike, kernel per spikelet, 1000 grain weight, biological yield and spike length were significantly by interaction effect. Study of result showed the best row pacing is 17 cm with 300 to 350 seeds per m2.

In order to study the effects of drought stress and plant density on the vegetative and reproductive traits of varieties of canola, a test was conducted as re-broken plots in the form of completely random blocks design with four repetitions in Boroujerd Agricultural Research Station in the agricultural year 2009-2010. In this experiment,the drought stress was studied in three levels include unstressed, two drought stresses (in the step after rosette and before beginning flowering) and three drought stresses (in the steps after rosette, before beginning flowering and filing sheath)in the main plot and different levels of plant density in three levels 6,10,and 14 kg consumed seed in each hectare in subplot and varieties of canola,three varieties Zarfam,SLM046 and Okapy in subplots. The results obtained from variance analysis of the traits under study showed that drought stress , plant density and their interactions have significant effect on the number of seeds per pod, 1000-seed weight, seed yield ,harvest index, oil percentage and oil yield of the varieties of canola. The most rate of oil percentage was obtained in unstress condition and plant density 10kg/ha in variety Zarfam that regarding more biologic yield and more seed yield, it caused increasing oil percentage, by increasing water level the oil percentage was increased.

In order to study interaction of salicylic acid and superabsorbent on agronomical characteristic and protein percentage of chickpea Var Hashem, an experiment was carried out in research farm of Islamic Azad University - Arak Branch in 2011. The experiment was as factorial based on randomize complete block design with three replications. The treatments were included salicylic acid at four levels 0, 0.4, 0.8 and 1.2 mM and superabsorbent at three levels 0, 9 and 18 kg ha-1. Results showed that interaction effects of salicylic acid and superabsorbent on number of sub-sub branch, length root, 100 grain weight, grain yield, grain protein percentage and productivity index was significant. Foliar application of 1.2 mM salicylic acid was increased grain yield by 25% as compared with control. Application of 9 kg ha-1 superabsorbent and foliar application of 0.8 mM salicylic acid productivity index was increased by 7.8% to compared with control. Application of 18 kg ha-1 superabsorbent and foliar application of 0.4 mM salicylic acid root length and grain yield increased by 12.5 and 40% to compared with control. Results also showed that by using salicylic acid and superabsorbent under drought condition can obtain acceptable yield.

This study was conducted at the 400 hectare Research Farm of Seed and Plant Improvement Institute in Karaj at 2009-2010. In this research 23 bread wheat lines and cultivars including 20 drought-tolerant and 3 drought-susceptible lines were considered in a randomized block design based on split plots with two irrigation treatments (normal and stress) with 3 replications. Irrigation treatments including normal and restricted irrigation were considered as main plots and wheat genotypes (23 genotypes) were considered as sub plots. Grain yield and the amount of soluble carbohydrate and starch in different tissues (stamen Leaf, spike, Peduncle and Penultimate Was measured. The results showed that drought stress was significantly reduced grain and the amount of soluble carbohydrate and starch in stamen Leaf, spike and Peduncle tissues and the increase of Soluble carbohydrate and starch in spike. In this study, sd-86-11 Tolerant line with 6.3 tons per hectare grain yield under water stress and full irrigation with 7.4 tons per hectare yield also SD-86-9Tolerant line with 6.2 tons per hectare grain yield under water stress and full irrigation with 6.8 tons per hectare yield, showed the highest yield under water stress and full irrigation and Darya, the susceptible line, with 3.5 tons per hectare grain yield under water stress and full irrigation with 5.3 tons per hectare yield showed the lowest yield under dry conditions.

This experiment was performed as split-split plot experiment in a randomized complete block design with three replications. The main plot was drought stress in four levels including normal irrigation (control), water cessation at flowering, pod ding and flowering to physiological maturity stages. The sub plot was spraying with natural products in three level including spraying with distilled water (control), humic acid and seaweed extract and sub-sub plot was three chickpea varieties Hashem, ILC 482 and local landrace (Miami). The results of this study indicated that the interaction effect of drought stress and natural product spraying was significant on number of pods per plant, 1000-seed weight and harvest index was significant. Interaction effect of natural product spraying and variety was significant on number of pods and grain per plant and harvest index was significant. Drought stress decreased yield in different varieties by 13%, however, application of natural products especially humic acid could mitigate drought stress through increment of number of pod and grain per plant by 50%. Varieties responses almost were the same however variety ILC 482 had more efficiency in response to natural products in compared with other varieties because of more pod and grain in plant after natural products application.