Abstract: The field trials were conducted to study the effect of different rates of nitrogen under spring cabbage-corn-winter cabbage rotation system .The results indicated that: the 0-60cm soil section inorganic N content remarkable influence the maximum N fertilizer rate to obtain the maximum yield of spring cabbage, winter cabbage, when the section inorganic N content is 142.2 kg/hm2, the spring, winter Cabbage N fertilizer rate to obtains the maximum yield were 236.2kg/hm2, 311.4 kg/ hm2 respectively; When the section inorganic N content is 244.0 kg/ hm2, the value were 174.2kg/ hm2, 296.5 kg/ hm2. The local custom N fertilizer rate was 1.8-3.2times that N fertilizer rate to obtain the maximum cabbage yield ,excess application N rate has caused NO3-N rich in the ground water. The N fertilizer rate and soil profile inorganic N content affects cabbage the N utilize rate, the cabbage -corn rotation system is advantage to enhancement the N utilize rate. Right amount N rate(90kg/ hm2) is simultaneously enhance the yield and the quality of Cabbage; When the N rate further enhances, the cabbage yield also may further enhance, but the quality drops; When the N rate is excessively high, then both the yield and quality of cabbage decrease. Thus to obtain the better quality vegetables in the production, must reduce the N fertilizer rate and cabbage yield.

Key words: cabbage, Rotation System, N fertilizer rate, saijiang blacksoil.