Evaluation of Different Banana Varieties on Fusarium Wilt TR4 Resistance by Phenotypic Symptom and Real-time Quantitative PCR

[Objective] Fusurium wilt was one of the most crucial constrain factors for sustainable development of banana industry.Developing a rapid evaluation methodology for TR4 resistance with different banana varieties in greenhouse would provide a basis of resistant variety screening and further variety improvement for TR4 resistance in the field trial.[Method]In order to identify resistant differences among tested materials against Fusarium wilt and screen the reliable resistant resources for future variety improvement,Baxi,Guijiao No.1 and our selected line Yunjiao No.1 were evaluated in the green house by the disease index survey in leaf symptom,stem dissection,real-time quantitative PCR after inoculation with Fusarium oxysporum f.sp.cubense Tropic Race 4 (Foc TR4) wild isolate (15-1)to plant roots.[Resuh]Yunjiao No.1 had the best performance among the three banana varieties at 25 and 45 days after pathogen inoculation in three experiments.The overall performance related to TR4 resistance from strong to weak was:Yunjiao No.1 ＞ Guijiao No.1 ＞ Baxi.The pathogen content of the inoculated soil had no significant difference among different banana varieties planted.The pathogen content in the corm of the Yunjiao No.1 was low and showed significant different from that in Bard (P ＜ 0.05),however,it showed no significant difference with that in Guijiao No.1.[Conclusion] By the rapid evaluation methodology for TR4 resistance with different banana varieties in greenhouse,we found Yunjiao No.1 had the best tolerance compared with the other two varieties,and it deserved field selecting.