两个‘黄冠梨’杂交F1代对白粉病抗性的遗传倾向

Genetic Tendency of Resistance of Two ‘Huangguanli’ Hybridized F1 Generations to Powdery Mildew

为梨树白粉病抗病基因定位和筛选奠定基础,采用田间自然发病调查法,调查‘早酥梨’ב黄冠梨’杂交F 1代215株实生树和‘锦丰梨’ב黄冠梨’杂交F 1代362株实生树的叶片白粉病发病情况,并分析两个黄冠梨杂交后代对白粉病抗性的遗传变异。结果表明:调查区梨树白粉病发生较严重且均匀,感病对照‘苹果梨’两年感病指数分别为63.78和62.78,平均感病指数为63.28±0.71,经鉴定,梨树白粉病病原菌为梨球针壳( Phyllactinia pyri );调查发现,‘早酥梨’高感白粉病,‘锦丰梨’感白粉病,而‘黄冠梨’抗白粉病,‘早酥梨’ב黄冠梨’杂交F 1代白粉病发病率为100%,平均感病指数为23.59±3.03,低于中亲值,遗传传递力为 59.78%,变异系数为92.31%;低于低亲值的实生树118株,占54.88%,抗病植株最多,占33.02%;‘锦丰梨’ב黄冠梨’杂交F 1代白粉病发病率为98.34%,平均感病指数为15.17±4.71,低于低亲值,遗传传递力为 56.46%,变异系数达到111.16%,低低亲植株有257株,占70.99%,高抗植株最多,占41.71%。F 1代群体均表现出低亲遗传倾向。

Based on the naturally predisposing disease method, resistance of 215 F 1 generations of ‘Zaosuli’בHuangguanli’ and 362 F 1 generations of ‘Jinfengli’בHuangguanli’ to powdery mildew was researched.The hereditary variation on the resistance to pear powdery mildew of two ‘Huangguanli’ hybridized combinations was analysised.The results would be arranged a foundation for the localization and screening of the disease-resistant genes.The results showed that the pear powdery mildew was serious and uniform in 2017 and 2018.The susceptible indexes of ‘Pingguoli’ were 63.78 and 62.78 respectively, and the average susceptible index of ‘Pingguoli’ was 63.28±0.71.The pathogen of the pear powdery mildew was identified as Phyllactinia pyri .‘Zaosuli’ was highly susceptible,‘Jinfengli’ was susceptible, and ‘Huangguanli’ was resistant to powdery mildew.In F 1 generation of ‘Zaosuli’בHuangguanli’, the incidence rate was 100%, the average susceptible index was 23.59±3.03 under the mid-parent value, Ta and CV were 59.78% and 92.31%, respectively.Moreover the number of F 1 generations that susceptible index was lower than low-parent value were 118 (54.88%), and the number of the resistant plants were the most (33.02%).In addition,in the F 1 generation of ‘Jinfengli’בHuangguanli’, the incidence rate was 98.34%, the average susceptible index was 15.17±4.71 under the low-parent value, Ta and CV were 56.46% and 111.16%, respectively.The number of F 1 generations whose susceptible index lower than low-parent value were 257 (70.99%), and the high resistant plants were the most (41.71%).The F 1 generation of all populations showed with low-parent genetic tendency.