黄瓜对霜霉病和白粉病抗性的相关性研究

以国内外29份典型黄瓜品种(系)和两个杂交组合的4个分离群体为试材,研究了黄瓜对霜霉病和白粉病抗性的相关性。结果表明:在苗期和成株期,29份黄瓜材料的霜霉病和白粉病病情指数之间的相关系数分别为0.6198和0.6772,均呈极显著正相关;K8×K18组合的BC1P1和F2群体的霜霉病和白粉病病情指数之间的相关系数分别为0.4925和0.4933,K10×K18组合分别为0.4976和0.2868,均达到极显著正相关水平;采用AFLP分析,发现E25M63-103标记与控制黄瓜霜霉病和白粉病的某个数量感病基因紧密连锁,进一步从分子水平验证了黄瓜霜霉病和白粉病某个抗性相关基因是紧密连锁的。

Study on the Resistance Correlation between Downy Mildew and Powdery Mildew in Cucumber

29 worldwide representative cucumber materials(K1-K29)and 4 populations from 2 crosses were employed for studying the resistance correlation between downy and powdery mildews.The result showed that correlation coefficients of disease indexes between downy mildew and powdery mildew were 0.619 8 and 0.677 2 at the seedling and mature stages respectively,which were extremely significant.The correlation coefficients of downy mildew and powdery mildew for BC1P1 and F2 individuals from the cross between K8 and K18 were 0.492 5 and 0.493 3,and they were 0.497 6 and 0.286 8 for the cross of K10 with K18,respectively.These four coefficients were all extremely significant too.By AFLP analysis,E25M63-103 marker was linked to some susceptible quantitative gene controlling both downy mildew and powdery mildew.The finding proved further some resistant gene of downy and powdery mildews linked to each other from molecular level.