Effects Of Calcium Feitilizer Apply On Different Grain-type Peanut Soil Enzyme Activities And Fertility In Barren Upland Red Soil

Arachis hypogaea is an important oil crop and cash crop in China. In the south red soil is the major zonal soil. Especially, the upland red soil is widely distributed and resourceful land. Due to the long-term effect of high temperature and rainy, alternating wet and dry season in this area with a subtropical monsoon climate, the loss of calcium and other nutrients are serious by leaching and surface runoff, which result in soil depletion, less favorable to crop growth and development. Peanut is a calcium addicted crop, and calcium deficiency causes a lot of empty pod. Therefore, in this study, we selected three typical grain type peanut varieties of hunan, large grain type(XiangHua 2008), medium grain type (XiangHua 55), and small grain type (LanshanXiaozi), and virgin barren upland red soil of southern China which was deficient in calcium. We conducted two treatment(no calcium apply treatment and calcium apply treatment) by soil column method to systematically analyzing the soil enzyme activity and fertility of peanut, the relationship between Soil enzyme activity and soil physical and chemical properties to determinate the differences between the three grain type peanut varieties in physiological adaptability on barren upland red soil with calcium deficiency of southern China and the potential mechanism. The results of the study were as follows:(1) The soil phosphatese and fungal catalase activity were increased, but the soil saccharase,protease and ureasea activity in all growth period by applying calcium in large and medium grain type varieties. While applying calcium in small grain type varieties opposite with large and medium grain type varieties. Then the effect on rhizosphere soil enzyme activity was better than that of surface soil (0-20 cm). From the point of the whole peanut growth period, The maximum of soil enzyme activity in the middle growth stages.(2) Calcium can effectively increase the soil pH, the soil organic matter, the hydrolysable nitrogen and the available potassium content, but the available phosphorous content was decreased.(3) After applying calcium in soil, on the one hand, promoted the peanut nutrient element content in soil, such as calcium, potassium, zinc, copper; Inhibit the toxic elements in the soil; on the other hand, such as aluminum, cadmium, lead, manganese, which particularly significant to decrease content soil effect.(4) The soil saccharase activity are positively correlated with soil organic matter, available potassium; the soil phosphatase are positively correlated with soil available phosphorous; the soil protease, urease available and soil hydrolysable nitrogen into positive correlation, but the urease is negative correlation with soil organic matter; the soil fungal catalase is positively related to soil organic matter, soil hydrolyzable nitrogen, but the soil pH, available phosphorus, potassium negative correlation effectively. After applying calcium, negative correlation significantly decreased or to positive correlation.