氮肥用量对旱地玉米产量及产值的影响

在湘南红壤丘陵区第四纪红壤旱地,通过田间试验研究不同氮肥用量与玉米产量、产值的关系。结果表明:施用氮肥能提高玉米的单穗粒重和百粒重,对有效穗数、株高、茎粗、穗粗影响不明显。施用合适的氮肥能明显提高玉米的籽粒产量以及产值,以N225处理的籽粒产量和产值最高,分别为4 570.6 kg/hm2、6 730.0元/hm2,比不施氮肥的处理分别增产37.3%、增收21.3%。施用氮肥可以提高籽粒和秸秆的总吸氮量,各施氮处理的氮肥利用率为3.8%～16.6%,以N225处理的氮肥利用率最高。

Effects of Nitrogen Fertilizer Rate on Yield and Output Value of Maize from Dry-land

A field experiment was carried out to study the relationship between different nitrogen fertilizer rates and yield or output value of maize planted in the quaternary red soil dry land in southern Hunan red soil hilly region.The results showed that applying nitrogen could increase weight of single ear and 100 kernel weight of maize,and it had little effect on effective ear number,plant height,stem diameter and ear diameter.Applying suitable amount of nitrogen could significantly increase yield and output value of maize.The grain yield and output value of maize in N225 treatment were the highest by 4 570.6 kg/hm2 and 6 730.0 yuan/hm2,respectively,which increased by 37.3% and 21.3% compared with no nitrogen treatment.The application of nitrogen fertilizer could increase the total nitrogen uptake of grain and straw,and nitrogen use efficiency of all nitrogen treatment ranged from 3.8% to 16.6%,the highest was in N225 treatment.