甲维盐对斜纹夜蛾幼虫肠道细菌的影响

【目的】斜纹夜蛾幼虫属杂食性、高食量的害虫,通过分子生物学手段对经甲维盐处理后的斜纹夜蛾幼虫肠道微生物进行比对,研究肠道共生菌群受毒剂刺激后的代谢变化,探讨菌株的自身代谢与甲维盐的作用受体的相关性。【方法】基于Illumina MiSeq技术测序平台,对取食甲维盐和未取食甲维盐的斜纹夜蛾幼虫中肠细菌的16S rRNA可变区进行高通量测序,分析对比细菌群落结构多样性。【结果】肠杆菌属、根瘤菌属在斜纹夜蛾的肠道中占优势地位,经过甲维盐处理后两者的丰度大幅下降。沙雷氏菌属和黄单胞杆菌属在处理后减少到几乎为零,相反,原先不占据优势的棒状杆菌属和甲醇杆菌属,处理后丰度明显上升。【结论】甲维盐处理后的优势菌群以及丰富度均发生变化,表明斜纹夜蛾的肠道菌群结构可能与甲维盐毒理机制有关。

Effect of methylretinoin on the intestinal microflora in larvae of Spodoptera litura

Aim] Spodoptera litura larvae are polyphagous and voracious pest. The intestinal microorganisms treated with methyvitamin salt were compared to characterise the metabolic changes of intestinal symbiotic microflora exposed to toxicants and the correlation between the metabolism of the strain and the receptor of methyl salt.Method] The midgut of S. litura larvae collected from the experimental field of Danzhou Agricultural Science Base in Hainan Province was dissected in the laboratory with or without emamectin benzoate immersion. The 16S rRNA variable region of bacteria in the midgut of S.litura larvae fed on methyl salt vs. non-methyl salt was sequenced on Illumina MiSeq sequencing platform with high through put to analyze the diversity of bacterial community structure.Result] Enterobacter and Rhizobium were dominant but their abundance decreased significantly after treatment with methyl salt. In addition, significant changes were observed in Serratia and Xanthomonas, with a decline almost to zero after treatment. The abundance of Corynebacterium and Methylobacterium, which not previously dominant, increased significantly after treatment.Conclusion] The dominant microflora and richness of S. litura treated with methyl salt were different after treatment, suggesting that the structure of intestinal microflora in S. litura larvae might be related to the toxicity mechanism of emamectin benzoate.