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由尖孢镰孢菌古巴专化型Fusarium oxysporum f.sp.cubense,Foc引起的香蕉枯萎病是香蕉生产上的毁灭性病害,自1996年以来已对我国华南地区香蕉生产造成了严重危害。传统上香蕉枯萎病菌生理小种的鉴定主要采用人工接种鉴别寄主尔后测定病菌致病性的方法,但实验周期长,且受季节影响。以来自澳大利亚的香蕉枯萎病菌生理小种1号(BW1)、2号(Race 2)、3号(Race 3)以及亚热带4号(BW4)为对照,对分离自我国华南地区主要香蕉产区(广东、广西、海南、福建等省区)的14株香蕉枯萎病菌的单孢菌株进行致病性测定,并结合热带4号小种(TR4)和亚热带4号小种(ST4)的分子特异检测方法,确定其生理小种类型;同时,利用ITS、TEF‐1α、IGS、histone H3、β‐tubulin等5个主要用于镰孢菌系统发育学研究的基因,研究不同地区不同来源的Foc菌株之间的亲缘关系及其与非病原尖孢镰孢菌的关系,并评价这5个基因在香蕉枯萎病菌生理小种鉴定上的应用价值。研究结果表明:(1)来源于我国华南地区的4号小种主要为热带4号小种;(2)TEF‐1α、IGS、histone H3等3个基因片段能够将Foc中不同生理小种的菌株划分成不同的系统发育谱系,与致病性测定的结果具有对应关系,也能较好地反映尖孢镰孢菌种内菌株的亲缘关系,可用于香蕉枯萎病菌生理小种鉴定;(3)我国Foc 1号生理小种的遗传多样性高于4号生理小种,Foc 1号生理小种的菌系与来自香蕉果实上的非病原尖孢镰孢菌的亲缘关系比其与Foc 4号生理小种的菌系的亲缘关系更近。
Fusarium oxysporum f.sp.cubense, Foc caused by Fusarium oxysporum f.sp.cubense, Foc is a devastating disease in banana production and has caused serious damage to banana production in southern China since 1996. Traditionally, the identification of physiological races of Fusarium oxysporum f. Sp. Fumigatus was mainly carried out by artificial inoculation to identify the pathogenicity of the bacterium, but the experiment period was long and influenced by the seasons. In this study, the main banana producing areas isolated from southern China were collected from BW1, Race 2, Race 3 and BW4 from Australia. 14 strains of Fusarium oxysporum were tested for pathogenicity in Guangdong, Guangxi, Hainan, Fujian and other provinces and autonomous regions. Combined with the molecular specificity test of TR4 and ST4 Method to determine their ecotypes. At the same time, Foc strains from different sources in different regions were studied using five genes mainly used in phylogenetic studies of Fusarium, such as ITS, TEF-1α, IGS, histone H3 and β-tubulin And their relationship with non-pathogenic Fusarium oxysporum, and to evaluate the application value of these five genes in the identification of physiological races of Fusarium oxysporum f. The results showed as follows: (1) Race 4 was mainly derived from South China. (2) TEF-1α, IGS, histone H3 and other three gene fragments were able to distinguish different races The strains were divided into different phylogenetic lineages, which had a corresponding relationship with the results of pathogenicity test, and could well reflect the genetic relationship of Fusarium oxysporum isolates, which could be used to identify the physiological races of Fusarium oxysporum f. ) The genetic diversity of Foc 1 race in China was higher than that of race 4 and the genetic relationship between Foc 1 race and Foc 4 No. Physiological race closer to the strains.