Gut yeast diversity of Helicoverpa armigera under different dietary conditions

Intestinal endophytic fungi have played an important role in the nutrition, detoxification and development of host insects during natural co-evolution. Insects also provide suitable living environment for endophytic fungi. Insect endophytic yeast is also one of the important flora. Currently, it is little known about intestinal endophytic yeast of host feeding on different dietary conditions. Helicoverpa armigera is an important pest of economic crop in Xinjiang of China. However, the composition and function of intestinal yeast community in H.armigera in Xinjiang remains unclear. In this paper, the structural composition of yeast microorganisms in the larvae of H.armigera was explored under different environments feeding on apple, pear, tomato, artificial diet(laboratory feeding), urtica fissa, sunflower, and zinnia (wild environment) by high-throughput sequencing. Results showed that a total of 43 yeast OUT readings were obtained, including 33 yeast genera and 42 yeast species. The yeast genera with a total content of more than 5% were Hanseniaspora (36.27%), Moesziomyces (21.47%), Trichosporon (16.20%), Wickerhamomyces (12.96%) and Pichia (6.38%). Hanseniaspora was predominant when fed indoors with fruits, whereas Moesziomyces was only detected in the wild group (urtica fissa, sunflower, zinnia) and the artificial diet group. After the larvae were transferred from artificial diet to apple, pear and tomato, the structure of intestinal yeast community changed, mainly reflected in the increase of relative abundance of Hanseniaspora and the decrease of Trichosporon . At the same time, the results of α diversity index (Chao1) indicated that the intestinal yeast microbial diversity of H.armigera fed on wild plants was higher than that of indoor artificial feeding, and the highest was group Z (17.17±4.37). PCoA and PERMANOVA analysis conclued that there were significant differences in the gut yeast structure of larvaes of H.armigera on different diets which is likely to relate to host adaptation.