海岛棉不同群体枯萎病抗性分析及评价

Analysis and Evluation of Fusarium Wilt Resistance for Diferent Populations in Sea Island Cotton(Gossypium Barbadense)

棉花枯萎病是棉花种植区常见的一种病害,目前在海岛棉中发病严重,它的发生和发展直接影响到棉花的产量和品质。为揭示海岛棉枯萎病田间发病特征,本研究通过对三个海岛棉不同遗传群体(包括由抗病亲本5 917和感病亲本Pimas-7组配的F2:4群体(P1),由143份海岛棉种质资源构建的自然群体(P2)以及由感病亲本新海14和抗病亲本06-146组配的RIL系群体(P3))的枯萎病抗病表型特征进行田间调查,并分析其在不同世代间的主要遗传规律。结果表明:(1)通过对海岛棉枯萎病发病特征进行分级统计,发现三个群体在花铃期的病情指数和病级均成正偏态分布,P1和P3群体在病级和病情指数分布上出现了超亲材料;(2)通过方差分析发现三个不同群体间的病情指数和病级均存在显著差异,其中P2群体在两个抗病性状上值最高,变异系数最小,P3群体在两个抗病性状上值最低,变异系数最大;(3)通过估算遗传力得出的海岛棉枯萎病抗性的广义遗传力在70%左右,为中等遗传力;(4)对搜集到的143份海岛棉种质资源进行聚类,共分为四大类,其中,新疆自育品种抗病性总体较好。本研究通过比较不同海岛棉种质资源的抗病性,筛选得到一批枯萎病抗病性较强的材料,可以为今后进行海岛棉抗病育种奠定基础。

F usarium wilt is a common disease in cotton and currently performes very serious in the sea island cotton(Gossypium barbadense). Its occurrence and development will directly affects yield and quality of cotton. The research investigated the phenotypic traits in the field of Fusarium wilt resistance in three different genetic populations, including an F2:4population constructed by the resistant parent 5 917 and the susceptible parent parent Pimas-7, an natural population constructed by 143 sea island cotton germplasms and an RIL population constructed by the susceptible parent parent Xinhai 14 and resistant parent 06-146, and to analyze the main genetic regulation among different generations, aims to discover the traits of Fusarium wilt in sea island cotton in the field. The results showed that:(1) Through making statistics in different levels for Fusarium wilt resistance of sea island cotton, it was found that all of three populations performed positive segregation distribution both in the disease levels and the disease index, and there were super parent materials in both P1 and P3 of two resistance traits;(2) Through analysis of variance it was found that there was significant differences among three differentpopulations both in the disease levels and the disease index, P2 with highest value in two resistance traits but least in CV and P3 with least value in two resistance traits but highest in CV;(3) Through heritability estimation it was concluded that the h B2 of Fusarium wilt resistance in sea island cotton was about 70%, belong to the medium heritability;(4) Through clustering these 143 sea island cotton germplasms could be divided into four groups according to the two resistance traits and the group included the varieties selected in Xinjiang performed best in Fusarium wilt resistance than others. This study compared the disease resistance among different germplasms of sea island cotton and screened an amount of materials performing great in Fusarium wilt resistance, hoping to make foundation of resistance breeding in sea island cotton.