氮素对水稻不同生育阶段根系形态特征的影响

在盆栽条件下,设计1g、2g、3g、4g纯氮4个施肥水平,研究其对扬稻6号不同生育时期、不同生育阶段根系生长的影响。结果表明：1)抽穗期每株不定根数累积量,主要取决于无效分蘖期每株不定根数的生长量,其次为有效分蘖期,再次为拔节长穗期,每株不定根总长度也如此;抽穗期每株根干重累积量主要取决于无效分蘖期每株根重的生长量,有效分蘖期和拔节长穗期所占比例差异不大;2)无效分蘖期根系生长量占抽穗期根系累积量的比例根系性状间存在着差异,根系性状综合程度越小,所占比例也越小;3)在不同生育阶段,根系生长量的多少主要取决于其生长速率的大小。

Effect of Nitrogen on Root Morphometrics at Different Stages in Rice

Pot experiment was carried out and four nitrogen application rates, 1, 2, 3, 4g/pot, were designed to investigate dynamic characteristics of root growth in a indica rice cultivar "Yangdao 6". Results showed as following: 1) The accumulated number of adventitious roots at heading was determined mainly by the increased number of adventitious roots per plant during unproductive-tillering period, followed by that during effective-tillering period and that during stem elongating and panicle bearing period, while length of adventitious roots showed the same trend. The accumulated dry weight of adventitious roots at heading was determined mainly by the increased dry weight of adventitious roots per plant during unproductive-tillering period, followed by that during stem elongating and panicle bearing period or by that during effective-tillering period; 2) There is differences among root traits which Proportion of increased of adventitious roots per plant at different stages to The accumulated of adventitious roots per plant at heading stage. The more root trait is simple, the more proportion is decrease; 3) Amount of root growth depended to a large extent on growth rate at different phases.