Comparative Studies On Effects Of Different Cultivation On Carbon-Nitrogen Metabolism Of Rice

The effects of six kinds of different cultivations off method of application (three-strong and three-high cultivation, recommended cultivation, high nitrogen cultivation, low nitrogen cultivation, organic -inorganic mixed cultivation, conventional cultivation) on activities of several key enzymes of carbon-nitrogen metabolism (such as sucrose synthase^ucrose phosphate synthase,ADPG-ppase, nitrate reductase, glutamine synthase,glutamine transferase,protease and so on.), content and transport of substrate of carbon-nitrogen metabolism,rice yield and protein content of brown rice of "weiyou 198" were investigated in this paper to screen optimum cultivation of fodder rice. Results were shown as follows:1. The recommended cultivation could enhance the activities of several key enzymes of carbon metabolism such as sucrose phosphate synthase of functional leaves and grain in milk stage,sucrose synthase of functional leaves,ADPG-ppase of grain and so on. Which further studies showed that the rice treated with the recommended cultivation, the potential of synthesizing sucrose was very higher, the power of using sucrose to synthesis starch was very more intense, therefore the yield rice was uplifted.2. As compared with other cultivations, the recommended cultivation could obviously promote activities of nitrate reductase of functional leaves in panic stage,glutamine synthase of functional leaves in full-heading stage and grain in milk stage,glutamine transferase of functional leaves in full-heading stage,protease of functional leaves in post-growth stage, which of enzymes are key enzymes of nitrogen metabolism. It demonstrated that assimilation of nitrogen was very more rapid, degradation of protein in functional leaves was very more intense, nitrogen source in grain was enough to synthesis protein, therefore the content of protein in brown rice was markedly uplifted in rice oftreatment of the recommended cultivation.3. The recommended cultivation could delay the senescent of leaves, increase the functional period of photosynthesis, the content of sucrose of treatment of the recommended cultivation in functional leaves was higher, and the amounts of transport of sucrose from leaves to grain took the first place in the process of grain maturity. Sucrose in grain was enough to synthesis starch. Compared with treatment of conventional cultivation, the yield of rice treated with the recommended cultivation, the organic-inorganic mixed cultivation, the low nitrogen cultivation, the high nitrogen cultivation, three-strong and three-high cultivation respectively increased by 38.99%,34.99%,33.33%,29.63%,3.70%.4. The content of total N in functional leaves of treatment of the recommended cultivation was higher, and the power of transport of total N was more intense. The reductive amounts of total N in functional leaves from tillering stage to mature stage were shown as follows: the recommended cultivation (23.03g/kg),high nitrogen cultivation (22.24g/kg),Organic-inorganic mixed cultivation (19.72g/kg),three -strong and three-high cultivation (16.34g/kg),low nitrogen cultivation (14.01 g/kg),Conventional cultivation (13.09g/kg). Moreover the content of total N and protein N in brown rice of treatment of the recommended cultivation are higher than those of treatment of other cultivations.