Abstract: The effects of different cultivation patterns on microorganisms and enzyme in tobacco soil was studied. The results showed that compared with chemical fertilizer, organic fertilizer could improve reproduction of bacteria in tobacco soil, and inhibit growth and reproduction of fungi, improve growth of actinomycetes during fast growing period, and improve reproduction of ammonifying bacteria. At maturation period nitrifying bacteria in 60% fertilizer base fertilizer+10% organic fertilizer base fertilizer+30% fertilizer top fertilizer（second pattern） obviously increased and increased percentage of 141.4% than 70% fertilizer base fertilizer+30% fertilizer top fertilizer（first pattern）. Organic fertilizer could stabilize activity of urease and keep high activity, activity of acid phosphatase was higher than first pattern during every period. Organic fertilizer obviously improved activity of invertase, increased percentage of 375% than first pattern at 60 days after transplant. Organic fertilizer could obviously improved activity of soil hydrogen peroxidase. Total enzyme activity of second pattern was stable and higher than first pattern during every growth period, average enzyme activity increased percentage of 41.9% than first pattern. This proved that organic fertilizer was good at reproduction of soil beneficial microorganism, increased enzyme activity, and improved conversion and absorption of nutrients.

Key words: cultivation pattern, organic fertilizer, tobacco, soil microorganisms, soil enzyme activity