氮钾营养对青花菜生长,花球产量与光合生理的影响

高氮低钾处理的青花菜植株生长最好，花球产量最高；低氮低钾、低氮高钾和高氮高钾处理均较低。高氮低钾处理比其他处理的叶片叶绿素与氮含量高，糖含量居中。钾素水平相同时，高氮能提高核酮糖－１，５－二磷酸羧化酶／加氧酶羧化活性；而在氮素水平相同时，高钾则降低ＲｕｂｉｓＣＯ羧化活性，提高ＲｕｂｉｓＣＯ加氧活性。低钾时高氮降低ＲｕｂｉｓＣＯ加氧活性；高钾时高氮则提高ＲｕｂｉｓＣＯ加氧活性。ＲｕｂｉｓＣＯ羧化活性

Effects of N, K Nutrition on Plant Growth, Curd Yield and Photosynthetic Physiology in Broccoli

The effects of N, K treatments on plant growth, curd yield and photosynthetic phy-siology of broccoli ( Brassica oleracea var. italica cv. Tokyo-green) were studied from 1988 to 1990. The results indicated that the high N low K treatment resulted in the best plant growth, the highest photosynthate accumulation and curd yield, and chlorophyll and nitrogen content in the leaves were also the highest, while the sugar content was in middle as compared with the other treatments. N, K treatments caused marked effects on RubisCO activity. When potassium nutrients were the same, high nitrogen enhanced RuBPcase activity; when nitrogen nutrients were the same, high potassium treatments decreased RuBPcase activity and enhanced RuBPoase activity. That showed there were the highest RuBPcase activity and RuBPcase/oase activity ratio, and the lowest RuBPoase activity in the high N low K treatment. Curd yield was positively correlated with RuBPcase and RuBPcase/oase significantly, and negatively correlated with RuBPoase activity insignificantly.