Toxoptera citricida (Kirkaldy) (Hemiptera: Aphidae): associated simbionts and interactions with secondary symbionts

Abstract

The obligate association of bacteria and arthropods, especially insects, results in various modifications to the host. However, symbiosis in insects goes beyond the insect-symbionts interaction. There is an intricate network that includes other microorganisms from the same host, such as the facultative symbionts, which can affect host development, host race selection, host resistance to entomopathogens and entomophages, transmission and acquisition of pathogens, and resistance to environmental conditions. The association of Acyrthosiphum pisum with its primary and secondary symbionts is well studied, being recognized the symbiont effects on at least the host i) nutrition, ii) resistance to heat stress, iii) natural enemies, iv) transmission of pathogenic virus and v) host plant utilization. Therefore, the elucidation of the interactions with symbionts and the role of symbionts in the association of the host with the diseases they vector, the host plant and their natural enemies are important because they can influence the predictability and management of pathosystems and measures of biological control of insect pests. Thus, this project aims to i) identify the symbiotic microbiota associated with the aphid Toxoptera citricida, the vector of citrus tristeza virus (CTV), in different host plants, ii) determine the role of secondary symbionts in the development of the host and iii) in the association of the host with its primary symbiont, iv) to indentify changes in the proteome of the host induced by secondary symbionts which could be interfere with the host response to natural enemies or with the disease they vector (CTV). Thus, we expect this project will allow a better understanding of the relationships between symbionts and their role in the biology of T. citricida, leading to the identification of molecules that could participate in the interaction with pathogens and natural enemies.