Composição e tempo de oferta de dieta artificial para adultos de Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae) visando sua criação massal

Abstract

Anastrepha fraterculus (Wiedemann, 1830) is one of the main pests of Brazilian fruit production. Ecologically correct methods such as the sterile insect technique (TIE) and biological control (CB) are alternative tools to reduce the dependence on the use of chemical insecticides. To implement TIE and CB, it is necessary to establish large-scale rearing to carry out the release of sterile insects and parasitoids. Aiming to intensify insect production in biofactories, improving processes and breeding techniques, this study aimed to define a diet and its time of offering to adults of A. fraterculus in order to increase large-scale production, maximize the reproductive capacity of insects and reduce costs. The work was carried out at the Experimental Station of Embrapa Grape and Wine, in Vacaria/RS. The experiments were carried out using the following diets: D1 (Control/CENA standard) - raw wheat germ + yeast extract (BIONIS® YE NS) + crystal sugar; D2 - raw wheat germ + yeast extract (BIONIS® YE NS); D3 - raw wheat germ + crystal sugar; D4 - raw wheat germ; D5 - yeast extract (BIONIS® YE NS) + crystal sugar; D6 - yeast extract (BIONIS® YE NS); and, D7 - crystal sugar. The pre-oviposition, oviposition and post-oviposition periods, fecundity, viability and longevity were evaluated. It was observed that A. fraterculus adults fed with D1 (control) - raw wheat germ + yeast extract (BIONIS® YE NS) + crystal sugar and D5 - yeast extract (BIONIS® YE NS) + crystal sugar, were more fertile with averages of (1,807.6 and 1,317.44 eggs) and presented higher average viability of (64.88 and 57.31%), respectively. The pre-oviposition period was (7.72 and 8.32 days) for D1 and D5, respectively. The respective parameters addressed constituted the experiment of food supply time. Thus, food supply times of 5, 10, 15 and 30 days were established, using the following diets: D1 (control) - raw wheat germ + yeast extract (BIONIS® YE NS) + crystal sugar; D2 - only water; D3 - restriction of water and food; and D5 - yeast extract (BIONIS® YE NS) + crystal sugar. Fecundity and fertility were evaluated. Diets D2 and D3 did not allow the insects to survive for data collection. For D1, at 30 days, an average fecundity of (571.58 eggs) was recorded, being higher than the other times. For D5, in general, females had lower fecundity, so that at 15 days a higher average was recorded (270.48 eggs). For fertility values, an average close to (52%) was recorded at 5 days of supply of the diets for D1. In general, fertility increased up to 15 days after food withdrawal, reaching average values of (80.67 and 58.07%) for diets D1 and D5, respectively. For the date of 30 days after food withdrawal and evaluation, it was observed that fertility decreased drastically for D5, indicating that females reached maximum fertility between 15 and 30 days of longevity. It is concluded that the supply of the standard diet D1 composed of raw wheat germ + yeast extract (BIONIS® YE NS) + crystal sugar generally presented the best biological parameters, superior to diets containing yeast extract also providing satisfactory results and that the presence of sugar increases longevity. In the case of the time of offering the diet, it is important that it is offered up to the 15th day of life, when an increase in fecundity occurs for the standard/Cena diet. Obtaining this information contributes to improving A. fraterculus breeding techniques in biofactories.