基于分离培养和高通量测序的芷江白蜡虫病原菌研究

Pathogens Analysis of Ericerus pela in Zhijiang Through a Culture-dependent Approach and High-throughput Sequencing

为了明晰引起湖南芷江侗族自治县白蜡虫发病的主要原因及病原种类,利用分离培养法和高通量测序技术,对分别从芷江李家界、胡家头、田家溪和杨家村采集的6份罹病白蜡虫样本(5份雄虫、1份雌虫)进行真菌群落组成和多样性分析。结果表明,胡家头、田家溪、杨家村的4份雄虫样本在真菌群落结构上高度相似,其优势病原菌均为渐狭蜡蚧菌(Lecanicillium attenuatum)(丰度达94%以上,分离率28.12%),而采集于李家界的雄虫样本真菌多样性较高,群落结构和组成也明显不同于以上4份雄虫样本(P<0.05),主要病原菌为六出花链格孢(Alternaria alstroemeriae)(分离率7.76%)和枝状枝孢菌(Cladosporium cladosporioide)(分离率9.75%)。采集自杨家村的雌虫样本真菌群落结构不同于雄虫,主要病原菌为松针刺盘孢菌(Colletotrichum fioriniae)(分离率18.50%)和一种横断孢属真菌(Strelitziana sp.)(丰度25.77%)。此外,芷江罹病的雌、雄白蜡虫在真菌群落组成上具有显著差异,而雄性白蜡虫的真菌群落结构受立地环境影响较大,种虫来源与白蜡虫发病无明显相关性。

To identify the main factors and the pathogens responsible for the disease of Ericerus pela in Zhijiang,a culture-dependent approach combined with the high-throughput Illumina MiSeq technology was used to investigate the fungal community structure and diversity of six infected Ericerus pela samples(five male samples and one female sample)collected from Lijiajie,Hujiatou,Tianjiaxi and Yangjiacun in Zhijiang.The results showed a high similarity in fungal community structure among four male samples collected from Hujiatou,Tianjiaxi and Yangjiacun,with Lecanicillium attenuatum being the dominant pathogen(abundance more than 94%,isolation rate 28.12%).The male sample from Lijiajie exhibited a significantly different community structure compared to those of the four male samples(P<0.05).This sample demonstrated relatively higher diversity,with Alternaria alstroemeriae(isolation rate 7.76%)and Cladosporium cladosporioides(isolation rate 9.75%)as the main pathogens.The female sample from Yangjiacun showed distinct differences in fungal community structure compared to the male samples,with Colletotrichum fioriniae(isolation rate 18.50%)and Strelitziana sp.(abundance 25.77%)as the dominant pathogens.Moreover,the fungal community composition and structure in infected Ericerus pela males significantly differ from those in infected females.These differences are mainly associated with the site environment rather than the origin of the breeding population of E.pela.