苦瓜种质枯萎病抗性鉴定与抗性遗传特征分析

Germplasm Screening and Genetic Analysis for Fusarium Wilt Resistance of Momordica charantia L.

枯萎病严重威胁苦瓜的产量和品质,为了探明其抗性遗传机制,筛选抗病资源,本研究建立了苦瓜枯萎病苗期接种鉴定抗性分级标准,并对188份苦瓜育种材料进行抗性评价;利用高抗自交系‘5-278’及高感自交系‘MC10-1’构建六世代遗传群体(P_(1),P_(2),F_(1),F_(2),BCP_(1),BCP_(2)),借助SEA软件对统计数据进行分析,筛选最佳遗传模型并分析苦瓜枯萎病抗性遗传特性。结果显示,188份材料中共筛选出高抗材料3份,抗病材料17份,与病圃鉴定结果基本一致。苦瓜枯萎病抗性遗传符合“MX2-ADI-AD”模型,由主基因和多基因共同控制,两对主基因的遗传显性度不同,分别为超显性和不完全显性;主基因遗传率在BCP_(1)、BCP_(2)及F_(23)个世代群体中分别为89.72%、88.43%、78.62%,表明枯萎病抗性主要受2对主基因控制。环境因素对3个群体的抗性遗传存在一定影响,分别占8.14%,11.57%,4.76%。本研究建立了苦瓜枯萎病的苗期接种鉴定分级标准,探明了枯萎病抗性遗传规律,为下一步的抗性育种及抗性基因定位提供参考。

Fusarium wilt seriously threaten the yield and quality of Momordica charantia L.(bitter gourd).In order to explore the genetic mechanism of resistance and screen disease resistance resources,the classification standard for the resistance of bitter gourd was established,and the resistance of 188 bitter gourd germpalsms were evaluated.Six generation populations(P_(1),P_(2),F_(1),F_(2),BCP_(1),BCP_(2)) were constructed by using the high-resistant inbred line '5-278' and the high-susceptible inbred line 'MC10-1'.Statistics were analyzed with the help of SEA software,the best genetic model and the genetic characteristics of bitter gourd Fusarium wilt resistance were analyzed.The results showed that a total of 188 materials were screened for 3 high resistance materials and 17 disease resistant materials,which were basically consistent with the results of the disease nursery identification.The inheritance of bitter gourd Fusarium wilt resistance fits the "MX2-ADI-AD" genetic model,was controlled by major genes and polygenes;the two pairs major gene showed different genetic dominance,respectively,superdominance and incomplete dominance.The heritability of major genes was 89.72%,88.43% and 78.62% in BCP_(1),BCP_(2) and F_(2),respectively,indicating that the Fusarium wilt resistance is mainly controlled by two pairs of major genes.Environmental factors had some influence on the inheritance of resistance in the three populations,representing 8.14%,11.57% and 4.76%,respectively.The study established the classification standard of Furarium wilt resistance at seedling stage of bitter gourd,and elucidated the genetic mechanism of the resistance,which could provide reference for the mapping of resistance genes and to the future breeding program of Fusarium wilt resistant bitter gourd.