发病史、品种和轮作组合预防烤烟青枯病试验

Controlling Ralstonia solanacearum of Flue-cured Tobacco by the Combination of Variety and Crop Rotation According to Disease Levels of Tobacco Fields

选择不同烟地进行发病史、品种和轮作年数组合试验，初步量化3种因素，以求能更有效地预防烤烟青枯病。结果显示：把烟地发病史划分为0.5％、10％和≥30 ％4档是基本合理的；可以用K326、RG11和K346作为目前贵州省烤烟推广品种中对青枯病不同抗性的代表品种。在当前以K326及抗性类似品种为主栽品种的前提下，当烟地发病史为5％时就必须轮作；若连作，其倒数第2炕采收前1～2d的平均病林率达22．1oA（6．3％～39．6％），即可能很快进入明显甚至重病史档。黄泥土的重病史烟地轮作2～3年后种K326的病指分别为42．1～53．1和37．6，轮作3年和15年以上，种植与K326抗性相近的G28，病指分别是为13．2～16．1和30．3，显示轮作玉米多年后种植K326之类品种，被青枯病明显或严重危害的风险仍然高。提出了根据烟地发病史选择品种争轮作年数组合的试验结果预防青枯痛明显危害的对策建议。

The Ralstonia solanacearum disease level of tobacco fields was divided into 0. 5 %, 10% and 30% classes, and K 326, RG 11 and K346 tobacco varieties were selected to stand for different resistant levels to Ralstonia solanacearum. The results showed that the tobacco field with 5% of disease level should be cropped rotationally, Otherwise, even if K326 with strong resistance to Ralstonia solanacearum was continuously planted the tobacco field with 5% of disease level, the disease level of the field was increased, and the tobacco field of yellow soil with a higher disease level was easy to infect Ralstonia solanacearum even if maize was planted in the field for several years.