Effects of different nitrogen application rates on spring maize yield and nitrogen fertilizer utilization efficiency under straw cover
This study, based on the Experiment of Straw Return , aimed to examine the effects of different nitrogen application rates on spring maize yield and nitrogen fertilizer utilization efficiency under straw cover , and defined the relationships between spring maize yield and nitrogen fertilizer application rates .In the experiment , straw cover was regarded as main plots and different amounts of nitro-gen fertilizer, i.e.0, 135, 180 and 225 kg· hm-2, were regarded as subplots.The production of spring maize and nitrogen fertilizer utilization efficiency were determined after harvest .The results showed that straw cover decreased plant height ( 2.71％-6.55％) , cob length (4.26％-10.1％), cob diameter (3.92％-7.74％) and 100-grain weight (0.67％-1.68％) in 0, 135 and 180 kg· hm-2 plots, thus resulting in a decrease of maize yield from 4.30％-11.0％ (P<0.05) .However, straw cover increased plant height by 6.41％, cob length by 6.38％, cob diameter by 5.67％and 100-grain weight by 4.29％in 225 kg· hm-2 plots, respec-tively, thus resulting in an increase of maize yield by 6.82％ (P<0.05) .Spring maize yield was positively correlated with the nitro-gen fertilizer application rate in plots with straw cover , i.e.both yield and yield components increased with the increasing nitrogen fer-tilizer application rate.With straw cover , both nitrogen agronomy use efficiency and nitrogen partial factor productivity decreased with the increasing nitrogen application rate , indicating that the enhancing effect on maize yield and nitrogen utilization efficiency brought by straw cover was associated with nitrogen application rate .Among the 4 nitrogen fertilizer application rates , 225 kg· hm-2 combined with straw cover was the most practical way in agriculture practice .
国家科技期刊平台
NSTL
万方数据
维普
