一种应用镰刀菌酸快速鉴评瓜类枯萎病抗性的方法

A Method for Quickly Evaluating the Resistance to Cucurbit Fusarium Wilt by Fusaric Acid

【目的】针对瓜类枯萎病抗性鉴评现行方法普遍存在的费时费力等问题,建立了一种可替代尖孢镰孢菌进行黄瓜、苦瓜等瓜类枯萎病抗性鉴评的高效便捷方法,为瓜类乃至其他作物枯萎病抗性育种及抗性基础研究提供便利条件。【方法】以黄瓜、苦瓜分别为子叶平展作物和子叶不平展作物代表,选取对枯萎病菌和镰刀菌酸抗、感性状一致的黄瓜、苦瓜材料,用合适浓度的镰刀菌酸溶液处理子叶叶盘或第一片真叶,根据子叶叶盘和第一片真叶的褪绿表型鉴评瓜类枯萎病的抗感表型。【结果】在适当浓度的镰刀菌酸处理下,24 h内抗、感枯萎病的黄瓜子叶叶盘和苦瓜真叶均出现不同程度的黄化和褪绿表型,感病材料黄化和褪绿的程度明显比抗病材料严重,与其枯萎病感/抗性状一致,根据颜色差异能够准确区分抗/感枯萎病的黄瓜、苦瓜材料及其F2分离群体中抗/感枯萎病的后代单株。【结论】镰刀菌酸处理可以用于黄瓜、苦瓜乃至其他作物枯萎病抗性的快速高效鉴评,尤其适用于对镰刀菌酸和尖孢镰孢菌抗感性状一致的作物材料。

【Objective】This study is carried out to establish an efficient and convenient method that can replace Fusarium oxysporum to evaluate the fusarium wilt resistance in cucurbits including cucumber and bitter gourd,and to facilitate the relevant breeding and basic research.【Method】Cucumber and bitter gourd were selected as cucurbitaceous representatives with flat and uneven cotyledons,respectively.Cucumber and bitter gourd materials with consistent resistance/susceptibility to F.oxysporum and fusarium acid were selected,and the cotyledon discor the first true leaf were treated with appropriate fusarium acid solution(FA).The FA induced different chlorotic phenotypes in the cotyledon discs and true leaves were evaluated,wich reflected the corresponding palnts having different resistance/susceptibility to F.oxysporum.【Result】Under the treatment with appropriate fusaric acid solution,the leaf discs of cucumber cotyledons and the true leaves of bitter gourd resistant or susceptible to fusarium wilt showed different degrees of yellowing and chlorotic phenotypes within 24 h.Obviously,the yellowing and chlorotic degrees of susceptible accessions were more serious than those of the resistant accessions,which were consistent with their fusarium wilt susceptibility/resistance traits.According to the color difference,one could accurately distinguish the resistance/susceptibility of the cucumber and bitter gourd accessions,but also their progeny in the derived F2 segregated population.【Conclusion】Fusaric acid can be used for rapid and accurate evaluation of the resistance to fusarium wilt in cucumber,bitter gourd and other crops.It is especially suitable for the accesstions with consistent resistance traits to fusarium acid and F.oxysporum.