Midgut and Insect Pathogens

The alimentary canal in insects is the primary location interfacing with their host organisms and other biotic and abiotic factors from the environment. The insect alimentary canal can be divided into three distinct regions, the foregut, midgut and hindgut, based on their embryonic origins, structure and physiological functions. The foregut and hindgut are derived from embryonic ectoderm and are covered by cuticle. The midgut is derived from embryonic mesoderm and does not have the protective cuticle covering. The midgut is the region of the alimentary canal that actively interacts with the gut content from the environment and performs the primary functions of food digestion and subsequent nutrient uptake. In direct contact with the gut contents without protection by cuticle covering, the midgut constantly faces physical, chemical and biological challenges from the environment. It is a primary target and portal of entry for various pathogenic organisms.

Bacterial pathogens primarily...