Duração ninfal, um critério de seleção de Podisus nigrispinus (Heteroptera: Pentatomidae) com maior potencial reprodutivo e capacidade de consumo?

• Autor(a) principal: Peluzio, Robson José Esteves
• Data de Publicação: 2012
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1183
• topic: Asopinae; Controle biológico; Predador; Reprodução; Seleção; Asopinae; Biological control; Predator; Reproduction; Selection; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA

Podisus nigrispinus (Dallas, 1851) (Heteroptera: Pentatomidae) is an important predator of agricultural and forest pests which is reared in the laboratory without specific mating criteria. The nymphal period may be used as a parameter for selection of Asopinae predators according to biological and reproductive characteristics, as well as its consumption ability. The objectives of this work were to study the oviposition rate and reproductive performance of P. nigrispinus females with short nymphal durations feeding on Tenebrio molitor (L., 1758) (Coleoptera: Tenebrionidae) with respect to the life table and consumption of Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae) in four consecutive generations of the predator. Treatments were composed of P. nigrispinus females with nymphal duration of 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 and 30 days in a completely randomized design. Females of this predator with shorter nymphal duration showed better biological and reproductive characteristics, including greater total numbers of eggs and nymphs, weight and oviposition rate in the first 35 days after emergence. Intrinsic rates (rm) and net reproduction (Ro) were higher for individuals with nymphal duration of 19 and 20 days, respectively. The survival rate (lx) was higher (75%) for individuals with nymphal duration of 19, 20 and 21 days. Extracted biomass and the A. gemmatalis consumption rate were greatest in the F3 generation. The number of eggs/female and nymphs/female were similar among the four consecutive generations. Ovipositioning of P. nigrispinus was greater in F1 than in the other generations. P. nigrispinus females with shorter nymphal duration had succession with greater reproduction capacity, which is maintained in the generations with nymphal durations of 19, 20 and 21 days. The biomass ingested and relative consumption rate of A. gemmatalis by females of this predator were higher in F3 than in the parental generation, and the selection method is therefore recommended for gains in quality and productivity maintenance.