Effects Of Different Nitrogen And Phosphorus Interaction On Nutrient Absorption And Utilization Characteristics And Yield Formation Of Dryland Wheat

In order to study the effects of-different fertilization conditions on material production,nitrogen and phosphorus utilization and yield formation of dryland wheat,the field experiment was carried out in Wanrong County,Shanxi Province in 2013-2014 to clarify under the condition of the different nitrogen application levels,the phosphorus levels and nitrogen phosphorus interaction,the difference of plant nitrogen and phosphorus utilization and yield formation of dryland wheat,exploring the best fertilization dosage.The main results are as follows:(1)Nitrogen fertilizer had higher the number of tillers,plant height,ear length and bearing spikelet numbers than CK,which increased by 15%-18%of spike number,10%-15%of number of grains per spike,4%-18%of 1000-grain weight,and 10%-13%of yield.The number of tillers at wintering stage was the highest under Nsss,and the highest number of tillers during jointing to maturity stage,plant height,ear length and bearing spikelet numbers were achieved under N390.And the number of spike,grains per spike and yield were the highest under N390,and the 1000-grain weight was increased with the increase of nitrogen application rate.The dry matter accumulation,nitrogen accumulation,nitrogen translocation amount before anthesis,nitrogen accumulation amount after anthesis and the contribution to the grain,the phosphorus accumulation amount were increased after fertilized.The highest dry matter accumulation,nitrogen and phosphorus accumulation,nitrogen translocation amount before anthesis,nitrogen accumulation amount after anthesis and the contribution to the grain were observed with N390 treatment under the condition of nitrogen application.(2)The total root length,root system area,root volume and root tips at the depth of 0-80 cm was improved after applying phosphorus fertilizer significantly,and P135 was highest.The number of tillers,plant height,panicle length,bearing spikelet numbers,plant dry matter weight and the ratio,and dry matter accumulation and its proportion during the jointing to anthesis stage were increased after applying phosphorus fertilizer,which increased by 10%-16%of spike number,1%of number of grains per spike,4%-11%of 1000-grain weight,5%-12%of yield.Under the condition of applying phosphorus fertilizer,the tiller number at wintering stage was the highest under P270,but no significant difference was observed with P135,the highest tiller number during booting to maturity stage,the dry matter weight,the dry matter accumulation during jointing to anthesis stage,spike number and yield were achieved under P135.Phosphorus accumulation amount and nitrogen accumulation amount at different stages,the phosphorus accumulation amount in the organs at maturity the phosphorus uptake and the proportion in the middle and early growth stages were higher after applying phosphorus fertilizer.P135 was highest,and P recovery,P agronomic efficiency,partial factor productivity from applied phosphorus were also highest under P135 treatment.(3)Nitrogen rate 390 kg·hm-2 combined with of phosphorus rate 135 kg·hm-2 achieved the highest effective panicle and yield.In general,The application of nitrogen fertilizer was beneficial to improve the effective panicle number,optimize the agronomic traits at the maturity stage to increase the yield,and promote the accumulation and operation of nitrogen,and nitrogen rate 390 kg·hm-2 was better.The application of phosphate fertilizer could promote the root growth,and optimize the yield composition to increase yield and phosphorus absorption,phosphorus efficiency,and phosphorus rate 135 kg·hm-2 was better.Nitrogen rate 390 kg·hm-2 combined with of phosphorus rate 135 kg·hm-2 was better.