Identification of resistance to bacterial wilt and verticillium wilt in different eggplant rootstock germplasm using quantitative genetic analysis

摘要

Four eggplant rootstock germplasm lines, )A01, )A02, JB61 and JB62, with different levels of resistance to bacterial wilt (BW) and/or verticillium wilt (VW), along with the cultivated species 'Rf were used to construct Fi hybrids. F2 and BCi crosses were made by crossing BW-resistant JA01 and highly BW-susceptible 'Rf, and highly VW-resistant JA02 and highly VW-susceptible 'Rf. Plants were infected with BW and VW by root dip inoculation with Ralstonia solanacearum and Verticillium dahliae. The results showed that BW resistance in eggplant rootstock germplasm JA01 was inherited in an incompletely dominant fashion and was controlled by more than two genes. JA02 resistance to VW was also of incomplete dominant inheritance, controlled by one or two genes, with one gene playing the leading role. Eight parental combinations displayed resistance to BW, four showed resistance to VW and eight were susceptible to the two diseases. Combining ability analysis showed that both the general and specific combiningabilities of the resistances to these two diseases reached a significant level, indicating that the resistances were simultaneously affected by additive and non-additive effects. Hayman quantitative genetic analysis suggested that resistance to BW was affected by a dominant effect, not the epistatic effect; resistance to VW was affected by both dominant and epistatic effects. It is also supposed that the genetic expressions of resistances to the two diseases interact in eggplant rootstocks. This studyprovides evidence for breeding disease resistance in rootstock germplasm.