超高产夏玉米干物质与氮、磷、钾养分积累与分配特点

探讨超高产夏玉米品种整株干物质与氮、磷、钾养分积累分配特点,为制定高产栽培管理措施提供依据.本文在大田条件下,以登海661(DH661)和郑单958(ZD958)为试验材料,比较研究了超高产夏玉米干物质与氮、磷、钾养分积累分配特点.结果表明,超高产夏玉米DH661在成熟期内整株干物质及氮、磷、钾积累量分别为33475.53 kg/hm2、369.76 kg/hm2、117.85 kg/hm2、285.78 kg/hm2,均显著高于ZD958,较ZD958分别高15.82％、23.72％、32.17％、21.89％.超高产夏玉米DH661的干物质和氮、磷、钾养分在叶片和茎秆中的分配比例均低于ZD958,而籽粒和根系中的分配比例高于ZD958,因而具有较高的养分收获指数与偏生产力.整个生育期内,DH661各器官的养分吸收速率均显著高于ZD958,具有较高的养分吸收效率；茎、叶及根系的氮、磷、钾养分吸收速率在灌浆期前保持较高水平,之后下降较快,而籽粒的氮、磷、钾养分吸收速率于灌浆期后增加较快.吐丝期后,DH661仍能吸收积累较多的养分,因此吐丝后适当追肥对于超高产夏玉米灌浆期养分充足供应至关重要.

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.