Characteristics of dry matter,accumulation and distribution of N,P and K of super-high-yield summer maize

The aim of this study is to investigate characteristics of dry matter and nitrogen(N),phosphorus(P) and potassium(K) nutrient accumulations and distributions of super-high-yield summer maize.Field experiments were conducted in 2010 and 2011 for the higher-yield corn cultivar,Denghai(DH661) and the commonly grown corn cultivar,Zhengdan 958(ZD958).The results show that the dry matter and N,P and K nutrient accumulation amounts per hectare of DH661 are 33475.53 kg,369.76 kg,117.85 kg and 285.78 kg at maturity stages of corn respectively,and compared with the ZD958,the dry matter and N,P and K nutrient accumulation amounts of DH661 are increased by 15.82%,23.72%,32.17% and 21.89% respectively.The proportions of dry matter and N,P and K nutrients in the organs of stems and leaves of DH661 are lower than those of ZD958,while the proportions of dry matter and N,P and K nutrients in the organs of grains and roots of DH661 are higher than those of ZD958.The rates of nutrients uptakes of DH661 are higher than those of ZD958 in the whole organs.The rates maintain high levels before the filling stage and decline very fast after the filling stage in the organs of stems,leaves and roots,and increase very fast after the filling stage in the grains.After the silking,DH661 still can uptake large amounts of the nutrients.As for DH661,the top dressing of the nutrients after the silking is very important to fill grains and attain higher yield.