Desenvolvimento e qualidade de Trichospilus diatraeae (Hymenoptera: Eulophidae) utilizando hospedeiros alternativos / Development and quality of Trichospilus diatraeae (Hymenoptera: Eulophidae) using alternative hosts

AUTOR(ES)
FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

23/11/2010

RESUMO

Parasitoids are important because of their diversity and they regulate populations of insects of different orders, however to use them in the field depends on studies to improve their mass rearing. The objective of this work was to study reproductive factors of Trichospilus diatraeae Cherian &Margabandhu (Hymenoptera: Eulophidae) on pupae of Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) aiming at mass rearing and dispersal of this parasitoid in sugar cane. The experiments were carried out in Laboratório de Controle Biológico de Insetos (LCBI) at Instituto de Biotecnologia Aplicada a Agricultura (BIOAGRO) at Universidade Federal de Viçosa (UFV) in Viçosa, Minas Gerais State, in the Laboratório de Entomologia (LE) at Faculdade de Ciências Agrárias (FCA) at Universidade Federal da Grande Dourados (UFGD) and in a comercial crop of sugar cane of Empresa Dourados S/A ‐ Açúcar e Álcool in Dourados, Mato Grosso do Sul State. Two species of Lepidoptera: A. gemmatalis and Diatraea saccharalis (Fabr.) (Lepidoptera: Crambidae) were reared in artificial diet and the natural enemy, T. diatraeae, on these Lepidoptera. Experiments with the objective of the development of T. diatraeae on A. gemmatalis pupae kept at temperatures of (18, 20, 22, 25, 28, 30 e 32oC); number of offspring from female of T. diatraeae at 24, 48, 72 or 96 hours of age on A. gemmatalis pupae at the same ages; number of offspring of T. diatraeae on A. gemmatalis pupae after being stored at zero or 5oC for one, three, six, nine or 12 days and dispersal of T. diatraeae in commercial crops of sugar cane were performed. Experiments were kept at 25 2oC, 70 10% of relative humidity and 14 hours of photophase and parasitism, emergency, number of offspring, longevity, sex ratio, width of cephalic capsule, length of life cycle of the descendants (males and females) and dispersal of T. diatraeae in sugar cane were the principal biological parameters quantified. Length of biological cycle (egg‐adult) reduced from 37.72 to 16.00 days when temperature increased from 18 to 30oC, respectively. Emergency and number of offspring of T. diatraeae were greater in the temperature range from 22 to 25oC, respectively. Threshold temperature and thermal constant (K) were 8.40oC and 328.41 degree‐days, respectively. Emergency, number of offspring, cycle length, sex ratio, longevity and width of cephalic capsule of males and females of T. diatraeae showed the same response when the effect age of pupae and female of parasitoid was evaluated. Thus, pupae of A. gemmatalis at up to 96 hours of age can be used for mass rearing of T. diatraeae using females at up to 96 hours of age. Cold storage (zero or 5oC) of pupae of A. gemmatalis not parasitized and with immature stage (pupae) of T. diatraeae in it, negatively affects reproduction of this parasitoid. Parasitism was reduced as releasement distance increased. However, females of T. diatraeae found and parasitized D. saccharalis pupae up to 12 meters from the releasement point, and this is the value of a preliminary approximation of dispersal of T. diatraeae on sugar cane at seven months of age of ratoon because of the complexity of factors involved in the field experiments.

ASSUNTO(S)

trichospilus diatraeae hospedeiro parasitismo fitotecnia trichospilus diatraeae hosts parasitism

ACESSO AO ARTIGO

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