Effects Of Density, Nitrogen Fertilizer Dosage,Irrigation Period On The Physiological Characteristics,Dry Matter Accumulation And Yield Of Grain Sorghum

2013April-10months, in the experimental base of Tongliao Agricultural Science Research Institute located in West Liaohe plain, with grain sorghum hybrid108, pass through complex126as test material, study the effect of nitrogen fertilizer application rate, planting density, irrigation times on dry matter accumulation and yield, physiological characteristics, results show that:1.2grain sorghum yield increased with the increase of planting density first increases and then decreases, the mixed108, mixed126highest yield reached8978.25kg/hm28459.55kghm2, and appeared in12.75thousands strains of/hm2density conditions, and the differences of yield the highest and lowest density conditions were attained a significant level; leaf area index with the process of growth stage increased first and then decreased, the same growth period increases with the increase of planting density, net photosynthetic rate, diurnal variation of transpiration rate showed a single peak type,13:00was the highest during the same period, the difference between the2varieties.2. with the increase of nitrogen fertilizer level,2varieties of grain sorghum yield increased initially and then decreased, yield by nitrogen fertilizer of300kg/hm2under the maximum reached9408.15kg/hm2,8844.90/hm2, respectively, and the maximum and minimum fertilizer production appeared significant difference; strain increased with nitrogen fertilizer gradually increased; leaf area index with the advance of growth stage increased first and then decreased, under different nitrogen fertilizer treatments, leaf area index of2varieties of grain sorghum in nitrogen fertilizer of300kg/hm2under maximum; affected chlorophyll content during grain filling stage, the net photosynthetic rate in the nitrogen fertilizer of300kg/hm2under, during the same period in108varieties through complex is higher, at the same time that is better than the yield potential through miscellaneous108through126.3.2varieties of grain sorghum seedling irrigation plant height, leaf area index were higher than the other irrigation; dry matter accumulation in seedling irrigation treatment was the highest in the same period, the difference between different varieties; irrigation net light2varieties of grain sorghum photosynthetic rate showed a single peak curve, the highest in12:00-14:00, with the highest seedling irrigation treatment; the yield performance, different irrigation times yields were higher than that of no irrigation, the irrigation treatments in seedling irrigation was the highest,2varieties of grain through mixed108, mixed126sorghum yield reached8974.95kg/hm2,8089.65kg/hm2.Above all, in127500strains of/hm2density, nitrogen fertilizer amount was300kg/hm, grain sorghum seedling irrigation, photosynthetic ability is strong, dry matter accumulation, higher yield, Tongliao area is the more suitable mode of cultivation of sorghum grain.