Age-dependent fecundity and fertility life tables of the predator Brontocoris tabidus (Heteroptera: Pentatomidae) under field conditions.

Reproductive potential, longevity, life expectancy, and fertility life tables of Brontocoris tabidus (Signoret) (Heteroptera: Pentatomidae), a predator of lepidopteran defoliators in eucalyptus (Eucalyptus spp.) plantations, were studied in the field. After a 50-d preoviposition period (emergence of adults to the deposition of the first egg mass), ovipositional activity of B. tabidus continued until females died at 160 d. Females laid an average of 4.2 eggs per day and 601.1 eggs in a lifetime. Gross and net reproductive rates were 216.7 and 75.8 females, respectively. Generation time was 146.1 d, the period for doubling the population was 23.4 d, intrinsic rate was 0.03, and finite population increase was 1.03. Number of females per generation increased at 33.4 times. Results from our field studies indicate that B. tabidus has greater potential reproduction, oviposition period, and longevity than was expected from previous laboratory experiments. This suggests that B. tabidus has potential as a biological control agent to limit economically damaging pests in eucalyptus plantations.

Development and reproduction of Podisus distinctus (Heteroptera: Pentatomidae) fed on larva of Bombyx mori (Lepidoptera: Bombycidae).

Biological control has been reducing the use of chemical products against insect pests, especially predatory Pentatomidae. Species of this group can present high variations in their life cycle as a result of their diet. Thus, the objective of this research was to study nymph development and reproduction of Podisus distinctus (Stäl, 1860) (Heteroptera: Pentatomidae) fed on Bombyx mori L., 1758 (Lepidoptera: Bombycidae) larvae (T1), compared to those fed on Tenebrio molitor L., 1758 (Coleoptera: Tenebrionidae) (T2) and Musca domestica L., 1758 (Diptera: Muscidae) larvae (T3) at a temperature of 25 +/- 0.5 degrees C, relative humidity of 70 +/- 2%, and photophase of 12 h. Predators fed on B. mori showed duration of the nymph phase (18.68 +/- 1.02) similar to those fed on T. molitor (18.32 +/- 1.49). Pre-oviposition and oviposition periods and number of egg masses, besides eggs and nymphs per female, were higher with B. mori (5.83 +/- 2.02; 15.00 +/- 7.40; 8.42 +/- 1.84; 296.69 +/- 154.75; and 228.55 +/- 141.04, respectively) while longevity of males and females of P. distinctus was 25.76 +/- 16.15 and 35.00 +/- 16.15 days with T. molitor, and 20.57 +/- 13.60 and 23.46 +/- 12.35 days with B. mori, respectively.

Development and reproduction of Podisus distinctus (Heteroptera: Pentatomidae) fed on larva of Bombyx mori (Lepidoptera: Bombycidae)

O controle biológico vem reduzindo o uso de produtos químicos no combate a insetos pragas, com destaque para pentatomídeos predadores, os quais apresentam variaçäes em seu ciclo de vida, principalmente em função do regime alimentar a que são submetidos. Assim, o objetivo deste trabalho foi estudar o desenvolvimento ninfal e a produtividade de Podisus distinctus (Stãl, 1860) (Heteroptera: Pentatomidae) alimentado com larvas de Bombyx mori L., 1758 (Lepidoptera: Bombycidae) (T1), comparado com larvas de Tenebrio molitor L., 1758 (Coleoptera: Tenebrionidae) (T2) ou Musca domestica L., 1758 (Diptera: Muscidae) (T3) à temperatura de 25 ñ 0,5§C, umidade relativa de 70 ñ 2% e fotoperíodo de 12 h. P. distinctus, alimentado com B. mori, apresentou semelhante duração da fase ninfal (18,68 ñ 1,02) em relação à alimentação com T. molitor (18,32 ñ 1,49). Os períodos de pré-oviposição e oviposição e os números de ovos postos e de ninfas por fêmea foram maiores com B. mori (5,83 ñ 2,02; 15,00 ñ 7,40; 8,42 ñ 1,84; 296,69 ñ 154,75; e 228,55 ñ 141,04, respectivamente), enquanto a longevidade de fêmeas e machos foi de 25,76 ñ 16,15 e 35,00 ñ 16,15 dias com T. molitor e de 20,57 ñ 13,60 e 23,46 ñ 12,35 dias com B. mori, respectivamente.

Lepidoptera pests collected in Eucalyptus urophylla (Myrtaceae) plantations during five years in Três Marias, State of Minas Gerais, Brazil.

Lepidoptera pest species from eucalyptus were collected in Eucalyptus urophylla plantations in the region of Três Marias, State of Minas Gerais, Brazil, every 15 days from June 1989 to June 1994 with five light traps. Twelve primary and 15 secondary pest species were collected in the period with an average of 13,387 and 812 individuals per light trap, respectively. Most collected primary pest species were Stenalcidia grosica (Geometridae), Iridopsis subferaria (Geometridae), Eupseudosoma aberrans (Arctiidae) and Psorocampa denticulata (Notodontidae), totalizing for the study period an average of 5,450, 2,162, 2,436 and 1,458 individuals per light trap, respectively. Idalus admirabilis (Arctiidae) was the most collected secondary pest species, averaging 652 individuals/trap. Most primary pest species were collected during the dry season, from April to July, whereas most secondary pest species were collected during the rainy season, from January to March. These differences on seasonal occurrence between the two groups could be due to the fact that many secondary pest species of Eucalyptus in Brazil pupate in the soil, and they need humidity to complete its pupal stage.