氮肥类型与施用量对夏玉米生长发育及氮肥利用的影响

以减少氮肥损失、提高夏玉米氮肥利用率为着眼点,对3种类型氮肥(普通尿素、包膜尿素、复合肥)不同施用量对夏播玉米品种郑单958与农大108的生长发育及氮肥利用的影响进行了研究。结果表明,在本试验施氮范围内(折合N 0~180 kg/hm2),两品种随施氮量增加而显著增产;同一施氮水平下以复合肥增产效应最好,但3种类型氮肥之间的产量差异不显著。两品种穗粒数随施氮量增加而增加,与氮肥类型关系不大,而千粒重受氮肥类型影响较大,且品种间表现有差异。LAI、干物重与叶片叶绿素含量均随施氮量增大而增大,且复合肥和包膜尿素对以上3个性状值的提高较普通尿素更明显。与普通尿素相比,包膜尿素与复合肥的氮肥利用率较高,但不能相应地提高氮收获指数。各类型氮肥的利用率均具有基因型差异。

Effect of Type and Application Rate of Nitrogen Fertilizer on Development and Nitrogen Utilization in Summer Maize

Aimed to reduce lose of nitrogen fertilizer(NF)and heighten nitrogen use efficiency(NUE)in summer maize,effects of different application rates of three types of NF(common urea,coated urea and compound fertilizer)on growth and development,NUE of summer maize cultivars Zhengdan958 and Nongda108 were studied in 2004.The main results as follows:Yields of two cultivars increased obviously with the increment of N application rate from 0-180 (kg/ ha).The increment effect to yield of compound fertilizer was best under the same application rate,but the difference between three types of NF was not prominent.Grain number per ear of two cultivars increased with the increment of N application rate,and its relationship with type of NF was very weak.1000-grain weight was affected any more by type of NF,and there existed difference between cultivars.LAI,dry matter weight and leaf chlorophyll content increased with the increment of N application rate,and they were heightened more obviously by compound fertilizer and coated urea than by common urea.Compared to common urea,NUE of coated urea and compound fertilizer was higher respectively,but their nitrogen harvest index could not be heightened correspondingly.NUE of three types of NF exist genotype difference.