S-3307和PP_(333)对水稻的壮秧增蘖作用

The effect of S-3307 and PP_(333) on bettering seedling and increasing tillering of rice

用不同浓度S—3307和PP333溶液浸种试验表明，这两种生长延缓剂对水稻秧苗都有明显的壮秧增蘖作用。其作用随浓度提高和浸种时间的延长而增强。用生长量（苗高×单株分蘖数）来判断最适施用浓度，在本试验条件下，对照秧苗的生长量为42．1；用0．5×10-6S—3307浸种72h的秧苗生长量为53．6；用5×10-6PP333浸种72h的秧苗生长量为52．7。说明以上浸种浓度和时间为最佳处理。用S—3307和PP333浸种后，水稻秧苗叶片叶绿素含量提高，光合性能改善。秧苗叶片在0～2℃低温下，各处理电导度比对照小，说明细胞结构遭受破坏程度减轻，质膜仍具有一定的半透性，使外渗物质减少，表现出电导度增加不多。

The test of soaking seeds with different concentrations of S-3307 and PP333 shows that these delayers can make seedling better and increase tillering of rice to a certain extent. And the higher concentration and the longer time be given,the better effect is. Using the growth increment (seeding height×tillering per plant) to determine the optimal concentratinn under this experimental condition, it shows that the best treatments are 0. 5 ×10 -6S-3307 for 72 hours and 5×10-6 PP333 for 72 hours, by which the growth increment are 53. 6 and 52. 7 respectively, while CK is 42. 1. The leaf chlorophyll content is increased and phntosynthetic capacity is improved after soaking the seeds of rice with S-3307 and PP333. Under the condition of low temperature of 0～2℃,it shows that the degree of cellular construction broken is lower and the cytoplasmic membrane still has some semipermeability, which makes less permeable substances go outwards. As a result, the electric conductivity increased just a little.