油菜素内酯对水稻幼苗生长及耐冷性的影响

用油菜素内酯(BR)对水稻进行浸种处理或幼苗喷雾,可促进幼苗在低生长温度下的生长,其株高、干物重,成苗率和叶片叶绿素含量均较对照明显增加。但幼苗在较高的生长温度下,处理组与对照组之间无显著差异。同时还发现,经BR处理的幼苗在低温下生长,其组织的电导率下降、膜酯不饱和脂肪酸中的亚麻酸含量及脂肪酸不饱和指数有所提高,幼苗可溶性糖含量也增加。这种变化与BR处理后水稻幼苗耐冷性的提高有关。

EFFECT OF BRASSINOLIDE ON RICE SEEDLING GROWTH AND ITS COLD RESISTANCE

With different concentrations of brassinolide(BR) for rice seed-soaking or seedling-spraying, we investigated its effects on seedling growth and cold resistance and theresults arc as follows: BR-treatments may enhance rice seedling growth at sufficientlylow growth temperature. Its plant height, weight of dry matter, rate of seedling-raisingand chlorophyll contents in leaf differ significantly from those of control (table 1-3).Under high growth temperature, the differences between the effects ot BR-treatmentson rice seedling growth and those of control are considerably meager. BR-treatmentsmay enhance the decrease of electric conductivity of rice seedling tissue, the contentsof unsaturated fatty acids (mainly linolenic acid) and unsaturati on index of cellmembrane lipoids and also the increase of soluble sugar contents of rice seedling (figure1-2, table 4 ). All these changes are concerned with the raising of cold resistanceof rice seedling under BR-treatments.