萝卜种质资源对黑腐病的抗性鉴定与筛选

对40份初选萝卜种质分别接种Xcc8004和XccBJ两个菌株,进行黑腐病苗期抗性鉴定,对其中8份代表性萝卜种质肉质根切片接种Xcc8004进行抗性鉴定和27份萝卜种质幼苗接种8个效应物基因进行过敏反应鉴定。结果表明:不同萝卜种质苗期对黑腐病的抗性存在显著差异,筛选出高抗Xcc8004的材料3份、抗病1份、中抗4份,高抗XccBJ的材料1份、抗病2份、中抗5份。萝卜苗期对Xcc8004和XccBJ的抗病性极显著相关,幼苗和肉质根对Xcc8004的抗病性极显著相关。筛选出17份对不同效应物表现过敏反应的萝卜种质。对效应物XC₀241表现过敏反应的种质数最多,对XC₀542和XC₀541表现过敏反应的种质数次之。不同抗源对不同效应物的过敏反应程度有所不同。稳定可靠抗病资源的获得为萝卜抗病育种和抗病机理的深入研究提供了基础材料。

Identification and Selection of Radish (Raphanus sativus L.) Germplasm with Resistance to Black Rot(Xanthomonas campestris pv. campestris)

Forty radish germplasm were inoculated with strain Xcc8004 and XccBJ of Xanthomonas campestris pv.campestris（Xcc） at seedling stage.The fleshy root of eight germplasm among them were sliced and inoculated with strain Xcc8004.Twenty-seven accessions of them were inoculated with eight effectors.The result indicated that radish germplasm′s resistance to black rot was significantly different.Three accessions showed highly resistant（HR）,one resistant（R）,and four moderately resistant（MR） to Xcc8004.One HR,two R,and five MR radish germplasms to XccBJ were identified.The resistance of radish seedling to Xcc8004 was significantly correlated to the resistance to XccBJ,and the resistance of seedlings and fleshy roots to Xcc8004 was also significantly correlated.Seventeen radish germplasms exhibited hypersensitive response to different effectors.The number of radish germplasms showing hypersensitive response to XC₀241 was the most,followed by hypersensitive response to XC₀542 and XC₀541.The extent of hypersensitive response in different germplasm to different effectors was not identical.The reliably resistant resources provide the basic materials in breeding for the radish resistance and studying resistance mechanism.