【摘要】 在盆栽条件下,设计1、2、3、4g·盆-14个施氮(纯氮)水平,研究其对武运粳8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;抽穗期每株不定根总长累积量主要取决于无效分蘖期每株不定根总长的生长量,其次是拔节长穗期,再次为有效分蘖期,每株根干重也表现出相同的趋势。2各处理不同生育阶段根系生长量占抽穗期根系累积量的比例有效分蘖期相对稳定,无效分蘖期和拔节长穗期变化较大。但无效分蘖期根系生长量占抽穗期根系累积量的比例平均值皆在50%以上,是影响抽穗期根系累积量的主要生育阶段。3在不同生育阶段,根系生长量的多少与其生长速率的大小有密切关系。更多还原

【Abstract】 Pot experiment was carried out and four nitrogen application rates, 1, 2, 3, 4 g·pot-1 (N), were designed to investigate dynamic characteristics of root growth in a Japonica rice cultivar, Wuyunjing 8. The results were as follows: 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. The accumulated length of adventitious roots at heading was determined mainly by the increased length of adventitious roots per plant during unproductivetillering period, followed by that during stem elongating and panicle bearing period and by that during effectivetillering period, while dry weight of adventitious roots showed the same trend. ② Root growth proportions during effectivetillering period to accumulated growth quantity at heading in all treatments were stable, but those during noneffectivetillering period and during stem elongating and panicle bearing period showed wide variation. Noneffective tillering period, which contributed more than 50% root growth quantity to the accumulated root growth at heading, was the main period influencing root growth accumulation. ③ Amount of root growth depended to a large extent on growth rate at different phase.更多还原