CAJ | 학술논문

为探明夏玉米各器官氮素积累与分配动态及其对氮肥的响应,以郑单958为材料,设置5个施氮水平进行了连续2年的大田定位研究.结果表明,除籽粒外各器官的氮素积累进程都呈单峰曲线,茎鞘在吐丝期达到峰值,而叶片、苞叶和穗轴则到吐丝后12 d 左右达到峰值,之后逐渐下降;籽粒和整株的氮素积累随生育进程持续增加,成熟期最高.与其他器官相比,叶片对氮素供给更敏感,氮胁迫使叶片氮素积累高峰提前,促进氮素提前向外转运,导致其率先衰老.施氮能提高各器官在各生育时期的氮素积累量和积累速率,但不改变氮素积累变化趋势.总体上,施氮量180 kg N hm–2可满足夏玉米对氮素的需求,获得较高的产量.以各器官氮素积累最大值与成熟期的差值计算,各处理再转运氮素对籽粒的贡献率均表现为叶片>茎鞘>穗轴>苞叶,各器官再转运氮素对籽粒贡献率之和平均为53.3%,其中苞叶和穗轴占12.3%,也是籽粒中氮素来源的重要组成部分.
위탐명하옥미각기관담소적루여분배동태급기대담비적향응,이정단958위재료,설치5개시담수평진행료련속2년적대전정위연구.결과표명,제자립외각기관적담소적루진정도정단봉곡선,경초재토사기체도봉치,이협편、포협화수축칙도토사후12 d 좌우체도봉치,지후축점하강;자립화정주적담소적루수생육진정지속증가,성숙기최고.여기타기관상비,협편대담소공급경민감,담협박사협편담소적루고봉제전,촉진담소제전향외전운,도치기솔선쇠로.시담능제고각기관재각생육시기적담소적루량화적루속솔,단불개변담소적루변화추세.총체상,시담량180 kg N hm–2가만족하옥미대담소적수구,획득교고적산량.이각기관담소적루최대치여성숙기적차치계산,각처리재전운담소대자립적공헌솔균표현위협편>경초>수축>포협,각기관재전운담소대자립공헌솔지화평균위53.3%,기중포협화수축점12.3%,야시자립중담소래원적중요조성부분.
A successive two years’ field experiment with five N application rates was conducted using hybrid Zhengdan 958. The results showed that the process of N accumulation in all organs except grain conformed to a unimodal curve in the whole life cy-cle. The N accumulation in blade, bract, and cob reached the peak at around 12 days after silking, and that in stem and sheath at silking stage and then decreased gradually. The N accumulation in grain and the whole plant continuously increased, and the maximum value appeared at maturity. Compared with other organs, blade was more sensitive to N supply and N deficit stress made the N accumulation peak in advance, accelerated blade N remobilization and promoted senescence of blade. N supply sig-nificantly improved N accumulation amount and N accumulation rate in all organs at various stages, but did not change the trend of N accumulation. On the whole, the demands of maize organs for N could be met at the N application rate of 180 kg N ha–1, and a higher grain yield also achieved. According to the maximum value of accumulated N in organs, the contribution of remobilized N from maize organs to grain showed a trend of blade>stem and sheath>cob>bract, and the mean total contribution rate was 53.3%, of which cob and bract accounted for 12.3%, showing an essential part for grain N, too.