木薯轮作年限对枯萎病高发蕉园土壤抑病性的影响

Effects of Different Years of Cassava Rotation on Soil Disease Suppression in High Incidence Banana Plantations

为探讨木薯轮作年限对香蕉枯萎病高发蕉园土壤抑病性的影响,试验选择连作12年香蕉枯萎病发病率达90.4%的蕉园,设轮作木薯年限1、2和3年共3个处理,同时在下茬种植香蕉,测定蕉园土壤抑病性的生物指标、非生物指标及下茬香蕉枯萎病的发病率。结果表明:轮作木薯后土壤总真菌数量、病原菌数量和p H值均显著降低,土壤可培养细菌数量、A/F值、B/F值和速效磷含量均增大,且轮作年限越长,效果越明显;随着轮作木薯年限的增加,下茬种植香蕉的放线菌的数量逐年增加,枯萎病的发病率由90.4%降低到40.2%;轮作木薯可有效防治香蕉枯萎病,但轮作年限需超过3年。

The effects of different years of cassava rotation on soil disease suppression in the plantations were discussed, in which banana were planted for 12 years and the incidence rate of wilt disease were 90.4 %. The results showed that cassava rotation significantly decreased soil fungi number, pathogen quantity and pH value, while increased the number of soil cuhurable bacteria, the values of A/F and B/F and avail- able phosphorus content. Furthermore, the longer the rotation years was, the greater the effect was. And that with the extensionof the rotation years, the number of actinomycetes increased in next-crepping banana plantations, while the incidence of wilt disease reduced from 90.4 % to 40.2 %. So cassava rotation can effectively prevent from banana wilt disease, and rotation years must be more than 3 years.