云南省魔芋与玉米多样性栽培控制魔芋软腐病

在云南省富源县魔芋与玉米多样性栽培区设置田间试验,分析了魔芋软腐病的发病规律、植株的生长情况及发病植株病原菌的分离频率。结果表明:魔芋与玉米轮作是控制魔芋软腐病的主要措施,它可以显著降低魔芋软腐病的死亡率,且将发病高峰期延迟1个月,轮作条件下间种控病效果比单种提高59%,间种茎基部带菌率显著低于单种;间作体系内不同栽培行植株株高差异显著,发病率差异不显著,但行间发病植株欧文氏杆菌的分离频率存在显著差异,散叶期和换头期根部和茎基部病原菌分离频率与行间距呈正相关。因此,玉米魔芋轮作间种互作条件下对软腐病的防治效果最好,间作系统内部玉米对魔芋病原菌具有一定阻隔效应。

Effects of diversity cultivation of konjac and maize in controlling konjac' s soft rot disease in Yunnan Province, Southwest China

A field experiment with diversity cultivation of konjac and maize was conducted in Fuyuan County of Yunnan Province to study the konjac’s soft rot disease incidence, plant growth, and isolation efficiency of Erwinia carotovora causing konjac’s soft rot. Among the test cultivation modes, konjac and maize rotation was most effective in controlling konjac’s soft rot disease, which could decrease the preliminary infection sources and delay the peak of disease incidence for one month. In the rotation field, intercropping maize with konjac decreased the disease severity by 59%, as compared with konjac monocropping, and the isolation efficiency of E. carotovora from the tuber of intercropped konjac was significantly lower than that of monocropped konjac. In intercropping system, there was a significant difference in konjac height but little difference in soft rot disease incidence among different cultivation lines. However, the isolation efficiency of E. carotovora from infected plant was significantly different, and there was a positive correlation between the isolation efficiency and the line distance. It was suggested that konjac and maize rotation combined with intercropping could be an efficient way for controlling konjac’s soft rot disease, and maize would be the physical barrier for the pathogen spread in intercropping system.