Modifications of reproductor system of Brontocoris tabidus (Heteroptera: Pentatomidae) after exposition to deltamethrin / Modificações do aparelho reprodutor de Brontocoris tabidus (Heteroptera: Pentatomidae) após exposição à deltametrina

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

Beneficial insects such as Pentatomidae predators can be negatively or positively affected by insecticides. This research studied the impact of the deltamethrin Decis 25CE, with the concentrations of 0,0165%, 0.033% e 0.066%, representing the treatments T1, T2 and T3, respectively, on the reproductive system of males and females of the predator Brontocoris tabidus (Signoret, 1852) (Heteroptera: Pentatomidae). This insecticide was applied on third instar nymphs of this predator at the temperature of 26 2C, relative humidity of 60 10% and photo phase of 12 hours. Nymphs of B. tabidus, that survived the treatments, were maintained in organza bag on Eucalyptus urophylla plants with Tenebrio molitor L. (Coleoptera: Tenebrionidae) pupae until emergence. The testicles and the ovaries of B. tabidus were extracted, observed its morphology and morphometry analysis included in resin for histological cuttings. The tracheal system, that supplies oxygen to the gonads is, probably, the main intoxication way to expose such structures to volatiles of the deltamethrin. This insecticide had higher impact on males than on females of B. tabidus, with progressive disorganization of the follicles and of the enclosed structures, and it delayed the development of its follicles in relation to the control. The own tunic of the testicles of B. tabidus was the most affected structure with a reduction in the thickness and continuity solution, besides thickening the terminal areas of the gonads. Alterations in the female gonad with the deltamethrin did not show a defined pattern, because the histological profile of individuals of this predator in the T2 was similar to that of the control. The deltamethrin increased morphologically the length and width of the gonad of B. tabidus and histological delayed or impeded cellular differentiation and the presence of maturation areas. Besides, this insecticide altered structures of the testicles and ovarioles as the hem of the follicle and own sheet, in the males, and peritoneal hems and own tunic in B. tabidus females compared to the control.

ASSUNTO(S)

zoologia aplicada brontocoris tabidus heteroptera morphometry deltamethrin morfologia morphology brontocoris tabidus histology morfometria reproductor system heteroptera deltametrina histologia aparelho reprodutor

ACESSO AO ARTIGO

Documentos Relacionados