N_(98s)×特青(亚种间杂交稻)抽穗后物质生产及分配特点研究初报

A PRELIMINARY STUDY ON THE PRODUCTION AND DISTRIBUTION OF DRY MATTER AFTER HEADING OF N_(98S)×TEQING (A TWO-LINE INTERSUBSPECIFIC HYBRID RICE)

对N×特青示范田中试区与肥料试验田各处理小区稻株分析结果表明:抽穗后,亚种间杂交稻N×特青比常规稻特青干物质生产能力强,灌浆速度快;地上部各器官占植株干重比例,前者叶片比重大于茎,后者茎比重大于叶。亚种间杂交稻对肥料反应敏感,抽穗后,干物质累积,植株高度,每穗总粒数和粒重均随施肥量增加而增加,在高肥区有利于进一步提高产量,但增施氮肥后,灌浆速度明显滞后。

After heading the dry matter production capacity and the grain filling speed of N98s× Teqing, a strain of two line intersubspecific hybrid rice excelled those of Teqing, a conventional variety. A significant difference between N98s× Teqing and Teqing existed in the dry matter ratio of various organs to the whole plant. In N98s × Teqing the percentage of leaf dry weight was higher than that of stem dry weight and in Teqing the proportion of stem dry weight larger than that of leaf.Two weeks after heading, the grain filling speed of the rice panicle reached its peak with large amounts of assimilation products transported from sheath to ear. That is a stage easy to lodge and special measures should be taken to prevent plants from lodging and damage by insect and disease.The two-line hybrid rice was sensitive to fertilizer application. After earing, the dry matter weight, plant height, total grains per panicle, filled grains per panicle and thousand-grain weight rose with the increase of fertilizer application. It would be advantageous to a further increase of rice yield in areas where the soil is fertile and heavily fertilized. However, the grain filling was obviously slower and prolonged after an increase of nitrogen fertilizer application.