海/陆嫁接棉花黄萎病抗性机理分析

Mechanism analysis of Verticillium wilt resistance in grafted cotton of sea island/upland cotton

为研究不同抗性棉花嫁接对棉花抗病性的影响,选取6个不同抗性的海岛棉和陆地棉品种嫁接,通过田间病情调查、病原菌PCR检测的方法,分析棉花的关键抗病部位与抗病机制.结果表明:海岛棉抗病品种作接穗的嫁接棉花的抗病能力显著强于陆地棉抗病品种作接穗的嫁接棉花,陆地棉抗病品种作砧木的嫁接棉花的抗病能力显著强于海岛棉抗病品种作砧木的嫁接棉花;海岛棉抗病品种根部和茎部的抗病性比其他品种高;病原菌在海岛棉抗病品种中的扩展繁殖速度比在其他材料中慢.上述结果表明,海岛棉的关键抗病部位为茎部,陆地棉为根部;海岛棉的抗病机制可能为耐黄萎病菌毒素或抗扩展,陆地棉的抗病机制可能为抗侵入.

In order to investigate the effect of grafting on cotton resistance to Verticillium wilt,six cotton varieties with different resistant levels were selected.The crucial resistant parts of these cottons and the underlying mechanism of disease-resistance were explored by field disease survey and PCR detection of pathogens.The results indicated that the disease-resistance of the grafted cotton with sea island cotton resistant varieties as scions was significantly stronger than that of upland cotton resistant varieties,and the disease-resistance of the grafted cotton with upland cotton resistant varieties as rootstocks was significantly stronger than that of sea island cotton resistant varieties.The disease-resistance of the roots and stems of sea island cotton resistant varieties was better than that of other varieties,and the pathogens expanded and multiplied more slowly in sea island cotton resistant varieties than in other materials.The above results suggested that the key site of disease-resistance in sea island cotton was the stem and in upland cotton was the root.The disease-resistance mechanism in sea island cotton might be the tolerance of the mycotoxins or the inhibition of pathogen migration,and in upland cotton the disease-resistance mechanism might be related to the against of pathogen invasion.