PP_（333）对油菜幼苗的生理效应

PHYSIOLOGICAL EFFECTS OF PP_(333) WITH DIFFERENT CONCENTRATION ON RAPE SEEDLINGS

ＰＰ_（３３３）能有效地抑制油菜幼苗下胚轴的伸长，提高根系干重、根冠比值、可溶糖、可溶性蛋白质和叶绿素含量，促进光合速率和光合产物向根部运输，提高过氧化氢酶和硝酸还原酶活性。但对超氧物歧化酶活性无明显影响。此外，还能增强幼苗根系活力和根系对￣（３２）Ｐ的吸收以及提高膜脂不饱和脂肪酸含量。０．１～０．５μｇ／ｍｌＰＰ_（３３３）处理的，秧苗健壮，素质好。叶柄细胞排列致密，根颈增粗，维管束发达，光合速率增加，呼吸速率明显降低，植物总干重增加。

Presoaking of seeds of rape(Braasica napus L. cv.89-94 )with PP_(333) effectively inhibited theeiongation of the hypocotyi of the seedlings,increased the dry weight of the root system , enhancedroot-to-shoot ratio and the content of soluble sugars , soluble protein and chlorophyll,raised photo-synthetic rate and pronoted thd transport of photosynthates to the root.PP_(333) enhanced CAT andNR activity and improved root vigor and the absorption capacity of ￣(32) P by rape roots.It alsoincreased the content of unsaturated fatty acids in the biomembranes.PP_(333) seemed to have noremarkable effect on SOD activity. paraffin wax section showed that PP_(333) resulted in a moredensely arranged petiole cellular structure,thicker root collar and a well-developed vascularbundle. In contrast,PP_(333) significantly decreased respiration rate and increased the total dry weightof the plant. Treated with PP_(333) at 0.1-0.5μg/ml,the seedlings appeared to be stronger and theirphysiological quality better.