香蕉枯萎病4号小种T-DNA插入突变体Focr4-1453表型特征及致病性分析

Phenotype and pathogenicity of Focr4-1453:T-DNA insertion mutant of Fusarium oxysporum f. sp. cubense race 4

尖孢镰刀菌古巴转化型是引起香蕉枯萎病的主要病原菌,呈世界多态性分布,其致病机理尚不清楚。Focr4-1453为T-DNA插入突变体库中筛选出的一株与致病性相关的突变体。在克隆出其失活基因之后,将野生型菌株中的相同基因进行敲除和互补,得到敲除突变体ΔFoc4-1453和互补突变体ΔFoc4-1453-cp-1。对获得的3株突变体进行生物学表型研究发现,这些菌株的菌落生长速度、产孢能力以及孢子萌发率较野生型菌株明显降低,且无法透过玻璃纸进行生长。致病性测定试验表明,该基因失活会导致病原菌侵染能力显著减弱。

Banana fusarium-wilt disease was caused by Fusarium oxysporum f.sp. cubense and it＇t pathogenesis is unclear. Focr4-1453 is a pathogenicity-related mutant strain and it is found from T-DNA library. We got the mutant gene cDNA full length, then knockouted and complemented this mutant gene from wild-type strain and named them ΔFoc4- 1453 and ΔFoc4-1453-cp - 1. The result showed that the biological phenotype of Foc r4-1453＇ ΔFoc 4-1453 and ΔFoc 4 - 1453-cp-1 changed. Their colony growth rates, spore production capacity and spore germination were lower than those of wild-tvne strain. In addition, their virulence siznificantlv reduced.