Application of innovative technologies associated with ionizing radiation, radiographic images and artificial intelligence in optimizing the production of the parasitoid Doryctobracon areolatus for the biological control of Fruit Flies

• Grant number: 24/09873-1
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2024
• End date: October 31, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Thiago de Araújo Mastrangelo
• Grantee: Thiago de Araújo Mastrangelo
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated researchers: Rafael da Silva Gonçalves ; Sandro Daniel Nörnberg

Abstract

The fruit flies (Diptera: Tephritidae) management in Brazil has been a challenge for the production sector, as control is predominantly carried out using synthetic chemical insecticides. An alternative is biological control using parasitoids. In this sense, in the last 10 years, research efforts have been directed towards native species, with Doryctobracon areolatus (Hymenoptera: Braconidae) being the one that presented the greatest potential for use and technologies developed for its mass production in the laboratory. However, as in the creation process of other species, a fraction of the hosts are not parasitized, causing the emergence of viable and fertile flies and once they emerge in the orchards due to release in the pupal stage, they can cause damage to the fruits. due to oviposition and consequent larval development. This fact creates the need to eliminate the emergence of fruit flies when the parasitoids are released in the pupal stage, increasing costs due to additional manipulation steps. Furthermore, even though the host has been rendered unviable, there will be a number of residual pupae. Considering the establishment of the release of parasitized pupae, the presence of residual pupae will interfere with the quantification and release of the appropriate quantity. Exposure of fruit fly eggs or larvae to gamma or X-ray irradiation, before they are parasitized, has been used to reproductively sterilize hosts in the sterile insect technique (TIE) and also to prevent the emergence of fertile flies. when releasing parasitoids in biological control (CB) programs. In this context, the project aims to evaluate the use of irradiation sources applied to two species of fruit flies Anastrepha fraterculus and Ceratitis capitata, considered the most important for fruit growing in the South and Southeast regions of Brazil and which cause losses in orchards in São Paulo and Rio Grande do Sul, to be used in the multiplication of the parasitoid D. areolatus aiming to inhibit the emergence of adult fruit flies without affecting the performance of the parasitoids. The studies will be conducted to evaluate: (i) the host phase (egg or larva) most suitable for irradiation; (ii) source and dose of gamma radiation; (iii) biological parameters of parasitoids reared in irradiated hosts; (iv) olfactory response of parasitoids; (v) search ability and parasitism in semi-field conditions; (vi) effect of predation on D. areolatus in the pupal stage; (vii) use of artificial intelligence tools to determine parasitism in the pupa stage. The know-how of the researchers from the Temperate Climate Agricultural Research Center (CPACT) in the biological control of insect pests with researchers from the Nuclear Energy Center for Agriculture at the University of São Paulo (CENA/USP) using X-ray for sterilization and images (radiographs) of insects to make the host unviable (fruit flies) and the differentiation of parasitized and non-parasitized pupae, respectively. Thus, it will be possible to advance another step to improve the biological control of fruit flies with the parasitoid D. areolatus. (AU)