水稻氮高产高效与低产低效两类品种株型特征差异研究

Differences of Plant-Type Characteristics between Rice Cultivars with High and Low Levels in Yield and Nitrogen Use Efficiency

以氮利用高产高效型和低产低效型的12个粳稻品种的大田试验研究了225kghm-2纯氮水平下株型特征的类型间差异,以及株型特征、倒伏性状、产量和氮肥利用率的相互关系。结果表明,水稻上三叶的叶长、叶披垂度,氮高产高效型品种显著低于氮低产低效型,平均分别低9.29%、65.3%;上三叶的叶宽、群体LAI、有效LAI、高效LAI和比叶重,氮高产高效型平均分别比氮低产低效型高29.25%、8.27%、13.32%、6.66%和5.82%。相对于氮低产低效型品种,氮高产高效型品种植株茎秆节间配置合理,抗倒能力增强。水稻的产量、氮肥利用效率与植株上三叶的叶长、叶披垂度均呈显著或极显著负相关,与上三叶的叶宽、群体LAI、有效LAI、高效LAI和比叶重呈显著或极显著正相关,与抗折力、弯曲力矩和秆型指数呈显著或极显著正相关。尤其是剑叶、倒三叶的叶长和叶宽对氮素利用效率的作用较大。说明良好的株型结构是氮肥利用效率提高的前提。

A field experiment with 225 kg ha^-1 N fertilizer application was carried out in 2006 and 2007 on the farm of Yangzhou university,Jiangsu province,China.Using 12 rice genotypes（six N-efficient and six N-inefficient） selected from 120 rice cultivars grown in Yangzhou during 2004 and 2005 to investigate the relationship among the plant-type characteristics,N use efficiency and yield performance.The results showed that the top three leaves length and drop-angle of high yield and N-efficient rice genotypes were 9.29%,65.30% lower than those of the low yield and N-inefficient ones,and the width of the top three leaves,population LAI,valid LAI,high valid LAI,and LW/LA（leaves weight/leaves area） of the former of were 29.25%,8.27%,13.32%,6.66%,and 5.82% higher than those of the latter on average respectively.The high yield and N-efficient genotypes had higher lodging resistance capability and more reasonable distribution for the length of internodes on stem than the low yield and N-inefficient ones.Yield and N use efficiency negatively correlated（significantly at P0.05 or P0.01） with the length and drop-angle of the top three leaves,while positively correlated（significantly at P0.05 or P0.01） with the width of the top three leaves,population LAI,valid LAI,high valid LAI,SLW,anti-broken strength,bender moment,and lodge index.Especially,the length and width of the flag and top 3rd leaves played an important role in the N use efficiency.It was indicated that good plant-type structure is a prerequisite for N use efficiency.