连作对烤烟生长和烟地土壤酶活性的影响

采用完全随机设计，通过连续6季盆栽试验，分析了灰岩黄壤和第四纪黄壤两种贵州大面积分布的烤烟土壤中，不同连作年限对烤烟生长和土壤酶活性的影响。结果表明：（1）连作严重影响烤烟植株的生长，种植各季及不同土壤类型间其生物量均达显著差异。（2）脲酶、酸性磷酸酶、蔗糖酶活性随连作年限的增加酶活性降低，过氧化氢酶活性则显著增强。（3）连作障碍在盆栽四季或五季时表现最为明显；就土壤类型而言，灰岩黄壤比第四纪黄壤更适宜烤烟连作。

The Effects on the Yields of Flue-Cured Tobacco and Activities of Main Soil Enzymes

The effects on the yields of flue-cured tobacco,activities of main soil enzymes were analyzed. By completely random design, the results with six seasons of continuous cropping showed that: (1)The yields of flue-cured tobacco in two soils were obviously reduced with increasing cropping year; Lime stones and clays formed in quaternary period also showed a significant deviation in the same cropping year. (2) The activities of urease, acid phosphatase, invertase became lower with continuous cropping, and the activity of catalase was increased significantly. (3)Continuous cropping problems of flue-cured tobacco in two soils were most obvious after four or five years; Lime stones was more suitable for continuous cropping of flue-cured tobacco than clays formed in quaternary period.