Gut microbiota of Spodoptera frugiperda rice and corn strains: diversity and function on host adaptation process

Abstract

The gut microbiota is an important contributing factor to several aspects of their host's physiology. In insects, symbiotic microorganisms can play important roles in host plant adaptation and speciation, for example. Spodoptera frugiperda, an important agricultural pest of several crops, currently has two well-established strains, which differ at genetic level and utilization of host plants. Symbionts associated with the gut of S. frugiperda may be playing a relevant role in the process of host adaptation and strain differentiation. Thus, the goal of this project is to establish the role of the gut microbiota in host plant utilization and adaptation in insects, using the S. frugiperda "corn" and "rice" strains as a model. For this purpose, the characterization of the diversity of the gut microbiota associated with the rice and corn strains of S. frugiperda when using different host plants (maize, rice, and cotton) will be accomplished under field conditions. This characterization will be performed by analyzing the 16S rRna gene. The functional contribution of the gut microbiota in the exploration of different host plants by each strain of S. frugiperda will be performed via metatranscriptomic, metabolomic and biological analysis of insects under laboratory conditions. Additionally, the effect of the gut microbiota replenishment on the fitness of maize and rice larvae when using sub-optimal hosts will also be assessed. Correlations between host genotypic diversity and gut microbiota diversity will be carried out assessing larvae from populations from different regions of Brazil and countries in Latin America, USA and Mexico. It will also be verified the distribution and spatial organization of the main symbionts into the eggs of S. frugiperda and how they remain associated with the gut and infect the ovaries by using FISH assays. Finally, horizontal gene transfer events from gut microbiota to the host S. frugiperda genome will be verified as well (AU)