| Research

Study shows the functions of the foam produced by the root leafhopper

Thesis evaluates the importance of the foam of M. fimbriolata, one of the insect pests of sugarcane

28.05.2019 | 20:59 (UTC -3)

Letícia Santin

The root sharpshooter, Mahanarva fimbriolata (Stål), is one of the main insect pests of sugarcane crops. Work carried out in the Postgraduate Program in Entomology, at the “Luiz de Queiroz” School of Agriculture (Esalq/USP), evaluated the importance of the foam produced and released by the nymph, the name given to the immature phase of the insect.

The nymph is easily recognized in the field due to its behavior of constantly producing and releasing a mucilaginous mass, similar to a foam, that covers its entire body while sucking sap from plant roots. Among the functions attributed to the foam are the protection of nymphs against high temperatures, desiccation and natural enemies.

However, experimental evidence to confirm these hypotheses is scarce. The thesis, authored by Mateus Tonelli and supervised by José Maurício Simões Bento, from the Department of Entomology and Acarology, evaluated the importance of foam for the thermal protection of nymphs. M. fimbriolata, its protective action against predators and microorganisms associated with insects and foam.

The study showed that the foam serves as an important thermal microhabitat for the nymphs, keeping them at a temperature close to the ideal for their development. “The foam, in addition to housing a diversity of bacteria previously reported as protective symbionts of insects and which probably come from the intestines of the nymphs, is also repellent to predatory ants and causes irritation when in contact with other insects”, said the author. .

The results obtained open new perspectives for future research that aims to investigate the importance of foam for the growth and development of leafhoppers and can also help future work in the search for new strategies to control this pest.

The research was supported by the São Paulo State Research Support Foundation (Fapesp), the National Council for Scientific and Technological Development (CNPq) and the Coordination for the Improvement of Higher Education Personnel (Capes).