Effects of Nitrogen and Phosphorus Regulation on Alfalfa Nitrogen Accumulation and the Nitrogen and Phosphorus Nutrients of Soil
The ‘Gannong No.3’ variety of alfalfa planted in the Northwest semi-arid areas with different nitrogen and phosphorus levels was selected as the studied material in the second year.The yield,crude protein content and nitrogen accumulation of alfalfa and alkali-hydrolyzable nitrogen,phosphorus content and dynamic changes of soil,as well as the correlation of soil urease,soil available nutrient,the dynamic change of alkaline phosphatase activity,enzyme activity with the total protein production and yield of alfalfa were investigated.The results showed that nitrogen fertilizer could significantly improve the yield and crude protein content of alfalfa ‘Gannong No.3’ variety.And the nitrogen and phosphorus contents of soil,soil urease and alkaline phosphatase activities increased after fertilization.The effects of nitrogen and phosphorus fertilizer (NP) on the nitrogen and phosphorus contents of soil were greater than single application.Correlation analyses showed that ‘ Gannong No.3’ alfalfa yield (y) had significant positive correlation with soil nitrogen content (x1),urease activity (x2),phosphorus content (x3) and alkaline phosphatase activity (x4).The linear regression equation was y =-2976.953 +53.577x1 +216.824x2 +58.534x3 +12.145x4(R2=0.874**).
NETL
NSTL
万方数据
维普
