Effect of Combined Application of Organic Fertilizer and Chemical Fertilizer on Enzymatic Activities in Soils with Tobacco-maize Rotation and Tobacco-rice Rotation in Yunnan Province

Effect of combined application of organic fertilizer and chemical fertilizer on enzymatic activities in soils with tobacco-maize rotation(soil A) and tobacco-rice rotation(soil B) in Yunnan province was studied to provide basis for rational application of nitrogen fertilizer and soil improvement.The results showed that application of organic fertilizer significantly increased urease,protease,invertase and phoshatase activities in soil A and soil B,while had no significant effect on catalase activity.The urease,protease,invertase and phoshatase activities in soil A were higher than that of soil B from 60.84% to 71.78%,from 37.64% to 53.03%,from 17.01% to 32.36% and from 24.61% to 51.77% respectively,while the catalase activity between soil A and soil B was not significantly different.C-N ratio in soil A was higher than that of soil B,but there was no significant difference between the two soils.Those indicated that combined application of organic fertilizer and chemical fertilizer was beneficial to improve enzymatic activity,promote transformation and circulation of nutrient elements,improve soil nutrient and promote plant absorption and utilization.