Effect of two fungicides in the rearing of Hypothenemus hampei (Coleoptera: Scolytidae) in artificial diet

Abstract

A limiting factor in massive insect culture under laboratory conditions is the presence of fungí and polluting bacteria, which come mostly from the rearing colony. causing significant losses. Among the more frequent polluting fungi are Aspergillus flavus and occasionally Aspergillus niger. Diverse substances have been used for their control, however, they can have adverse effects on the reproduction of the insect. For this reason, the in vitro effect of the fungicides Carbendazim at 0,3%, and Thiabendazol at 0,05; 0,04; 0,03; 0,02 and 0,01 % was evaluated, added to Sabouraud Dextrose Agar (SDA) culture medium and incorporated to the diet. The greatest in vitro inhibitory effect was caused by Carbendazim, producing an inhibition halo of 4,36 cm, followed by the Tiabendazol 0,03%, with an inhibition halo of 3,42 cm. In the treatment with Carbendazim (22,3 ± 9 O.E.}, the production of biological stages of the coffee borer after 30 days resulted in the greatest average of biological stages, followed by the control (19,7 ± 8,9 D.E), with significant differences (Tukey 5%) with respect to Tiabendazol (16,5 ± 7 D.E). Both, instar developing time and the aspect and morphology of the different biological stages were similar to the control. The results indicated that in the diet, the fungicide Carbendazim does not present detrimental effects on the reproduction of the borer. making possible its use programs of mass rearing of Hypothenemus hampei, reducing simultaneously the contamination risks.