Specificity of gut microbial community in three ecologically similar species of planthoppers with different host plant ranges

The three ecologically similar species of hemipteran sucking insects, brown planthopper (BPH) Nilaparvata lugens, small brown planthopper (SBPH) Laodelphax striatellus and white-backed planthopper (WBPH) Sogatella furcifera are destructive pests causing severe damage to rice throughout Asia, but they have different host plants that BPH is monophagous insect just feeding rice, WBPH and SBPH are oligophagous insects additionally feeding wheat and barley and SBPH can also feed maize. This study was investigated the gut bacterial communities in BPH, WBPH and SBPH by high-throughput amplicon sequencing in order to explain the differences in host range (SBPH>WBPH>BPH) and feeding habit (BPH with monophagy vs. WBPH and SBPH with oligophagy) of the three ecologically similar species of planthoppers. It was revealed that the gut bacterial flora in BPH was the most complex, and that in SBPH was the simplest. The diversity of the gut bacterial community in BPH was significantly higher than that in WBPH and SBPH, respectively, there was not only significant difference in alpha-diversity metrics but also in beta-diversity metrics. KEGG enrichment analysis furtherly indicated that there was significantly different in the relative abundance of some functional categories (including those related to the biosynthesis of amino acids, fatty acids, lipids and carbohydrate) among BPH, WBPH and SBPH, which were closely related to their nutrient absorption and metabolism. It is presumed that the differences in abundance and composition of the gut bacteria in BPH, WBPH and SBPH may lead to different nutrient absorption and metabolism, which furtherly alter their host range and feeding habit.