Key Laboratory of Agro-biodiversity and Pest Management of China's Ministry of Education, College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, China.
College of Agriculture & Biology Technology, Yunnan Agricultural University, Kunming, 650201, China.
BMC Microbiol. 2020 Mar 11;20(1):58. doi: 10.1186/s12866-020-01740-8.
The potato tuber moth (PTM), Phthorimaea operculella (Zeller), is a worldwide pest that feeds on both the leaves and tubers of potato plants. PTM larvae can digest leaves, or tubers, resulting in serious damage to potato plants in the field and potato tubers in storage. To understand how midgut bacterial diversity is influenced by the consumption of these two tissue types, the symbiotic bacteria in the potato-feeding PTM midgut and the endophytic bacteria of potato tissues were analyzed.
At the genus level, the bacterial community composition in the PTM midgut was influenced by the tissues consumed, owing to their different nutrient contents. Escherichia_Shigella and Enterobacter were the most dominant genera in the midgut of leaf-feeding and tuber-feeding PTMs, respectively. Interestingly, even though only present in low abundance in leaves and tubers, Escherichia_Shigella were dominantly distributed only in the midgut of leaf-feeding PTMs, indicating that specific accumulation of these genera have occurred by feeding on leaves. Moreover, Enterobacter, the most dominant genus in the midgut of tuber-feeding PTMs, was undetectable in all potato tissues, indicating it is gut-specific origin and tuber feeding-specific accumulation. Both Escherichia_Shigella and Enterobacter abundances were positively correlated with the dominant contents of potato leaves and tubers, respectively.
Enrichment of specific PTM midgut bacterial communities was related to different nutrient levels in different tissues consumed by the insect, which in turn influenced host utilization. We provide evidence that a portion of the intestinal microbes of PTMs may be derived from potato endophytic bacteria and improve the understanding of the relationship between potato endophytic bacteria and the gut microbiota of PTMs, which may offer support for integrated management of this worldwide pest.
马铃薯块茎蛾（PTM），Phthorimaea operculella（Zeller），是一种世界性的害虫，它既吃马铃薯植物的叶子，也吃块茎。PTM 幼虫可以消化叶子或块茎，导致田间马铃薯植株和贮藏期马铃薯块茎严重受损。为了了解中肠细菌多样性如何受到这两种组织类型的影响，分析了以马铃薯为食的 PTM 中肠共生菌和马铃薯组织内生菌的共生细菌。
在属水平上，由于组织消耗的营养成分不同，消耗两种组织的 PTM 中肠的细菌群落组成受到影响。Escherichia_Shigella 和 Enterobacter 分别是食叶和食块茎 PTM 中肠最主要的属。有趣的是，尽管在叶片和块茎中含量很低，但 Escherichia_Shigella 仅在食叶 PTM 的中肠中占优势，表明通过食叶，这些属的特定积累发生了。此外，Enterobacter 是食块茎 PTM 中肠最主要的属，在所有的马铃薯组织中都无法检测到，这表明它是肠道特有的起源和块茎特异性积累。食叶 PTM 中肠的 Escherichia_Shigella 和 Enterobacter 丰度与马铃薯叶片和块茎的主要含量呈正相关。
特定 PTM 中肠细菌群落的富集与昆虫所消耗的不同组织中的不同营养水平有关，而这反过来又影响了宿主的利用。我们提供的证据表明，PTM 部分肠道微生物可能来自马铃薯内生细菌，并增进了对马铃薯内生细菌与 PTM 肠道微生物群之间关系的理解，这可能为这种世界性害虫的综合管理提供支持。
