大豆生长发育与根瘤形成的关系

为明确根瘤生长发育与大豆生长发育的关系，通过温室盆栽试验持续观察和研究了不同生长时期大豆根长、根系生物量、株高、植株生物量、根瘤重量和数量的变化关系。结果表明，大豆整个生育期内株高、植株干重、根系干重和根瘤鲜重的变化均从缓慢增长、迅速增加、到迅速下降、再到缓慢下降的过程。株高、植株干重、根系干重和根瘤鲜重的最大值分别出现在苗后的66天、72天、66天和60天。根长在出苗后一直处于较快增长期，到出苗后48天到78天均维持在一个不显著的缓慢增长期。而根瘤数量在出苗后的20天至30天迅速激增，然后经过一个缓慢增殖期，至54天达到最大值后开始下降。由此得出，大豆根瘤数量在植株生长早期迅速增长且在最大值附近维持较长时期；而根瘤鲜重生长规律同植株地下部或地上部干重的增殖规律相似。

Relationship Between Plant Development and Root Nodule Formation of Soybean

The present study was carried out to uncover the relationship between root nodule and plant growth development of soybean. Root length, root biomass, shoot length, shoot biomass, root nodule number and root nodule weight of soybean was examined regularly during the whole growth period by pot experiment in green house. The result was showed that shoot height, shoot dry weight, root dry weight and fresh nodule weight were changed from slowly rising to fast rising to fast declining to slowly declining. The maximum value of shoot height, shoot dry weight, root dry weight and fresh nodule weight were appeared at 66 days, 72 days, 66 days and 60 days after emergence respectively. However, root length increased fast after emergence. Root length kept in a stable period during 48 days to 78 days after emergence. Number of root nodule increased sharply during 20 days to 30 days after emergence. Then it was increased slowly. After reaching its maximum 54 days after emergence, number of root nodule began to decrease. The above results indicated that number of root nodule of soybean was increased rapidly during early-growth period and kept at the maximum up and down for a long period. The growth rhythm of fresh nodule weight was the same as that of shoot and root dry weight.