Josemar Foresti

Biologia e exigências térmicas de Spodoptera cosmioides (Walk.) (Lepidoptera: Noctuidae)

O objetivo do trabalho foi estudar a biologia de Spodoptera cosmioides (Walk.) em diferentes temperaturas e determinar suas exigencias termicas, visando fornecer subsidios para a criacao do inseto em laboratorio. Para isso, os periodos embrionario e pos-embrionario foram avaliados em sete temperaturas (14, 18, 22, 25, 28, 30 e 32oC), em câmaras climatizadas, com fotofase de 14h. As lagartas foram criadas em dieta artificial, tendo como fontes proteicas feijao branco, farelo de soja, levedura de cerveja, germe de trigo e leite em po. A duracao do periodo embrionario decresceu com o aumento da temperatura na faixa de 14°C a 25°C, mantendo-se constante entre 28°C e 32°C. Para os demais estagios (lagarta, pre-pupa e pupa), foi observada uma relacao inversa entre a temperatura e a duracao na faixa de 14°C a 30°C, estendendo-se a 32°C para pupas. A duracao da fase de pupa dos machos foi maior do que das femeas, o que promoveu assincronia na emergencia de adultos. As temperaturas bases do periodo embrionario, fase de larva, pre-pupa, pupa e ciclo total foram 9,34°C; 11,65°C; 9,65°C; 11,08°C e 11,23oC, com constantes termicas de 62,73 graus-dia (GD); 254,61 GD; 33,42 GD; 177,55 GD e 525,11 GD, respectivamente. Avaliando-se, separadamente, a fase de pupa, as temperaturas bases foram 11,25°C para machos e 10,81oC para femeas, com constantes termicas de 188,26 GD para machos e 165,47 GD para femeas. Para o ciclo total, a temperatura base e a constante termica para machos foram 11,28°C e 535,85 GD. Para as femeas, estas mesmas variaveis foram 11,15°C e 513,17 GD. Concluiu-se que a faixa de temperatura mais adequada para o desenvolvimento de S. cosmioides situa-se entre 25oC e 28oC, na qual pode-se obter de 9,6 a 11,7 geracoes anuais do inseto, em condicoes de laboratorio.

Desenvolvimento e exigências térmicas de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae)

The aim of this study was to evaluate the development of Trichogramma pretiosum Riley on eggs of Bonagota cranaodes (Meyrick) under different temperatures. B. cranaodes eggs were maintained under seven constant temperatures (14, 18, 20, 22, 25, 28 and 30oC), 70 ± 10% R.H. and, 14 h L. Forty replicates with 20 parasitized eggs each were kept in glass tubes (8.5 x 2.5 cm) covered with a plastic film. The method of hyperbole was used to calculate the temperature threshold (Tb) and the thermal constant (K). The Tb obtained was 11.9oC and to thermal constant was 153,4 DD. The most favorable temperature range was from 25oC to 30oC, at which the shortest egg-adult development period and the highest survivorship were observed.

Aspectos biológicos de Argyrotaenia sphaleropa (Meyrick 1909)(Lepidoptera: Tortricidae) em Dietas Artificiais com Diferentes Fontes Proteicas

Biology aspects of Argyrotaenia sphaleropa Meyrick fed on artificial diets with different protein sources were studied: D1-white bean, wheat germ, soybean protein and casein; D2-common bean and yeast and D3-common bean, yeast and wheat germ, evaluating the duration and viability of all developmental stages (egg, larval, prepupa and pupa) and of the total cycle (egg-adult), sex ratio, pupa weight, fecundity, longevity and life table of fertility. Tests were conducted in the laboratory at 25±1°C, 65±10% RH and 14h of photophase. Duration of the egg stage was 6.6 days on all diets. The longest duration of larval and prepupal stages on D1 and pupal stages on D2, resulting in a longer duration of the total cycle on these two diets (30,9 and 30,8 days). The total viability was higher than 62% on all diets, and there was no statistical difference among the treatments. The number of instars was four or five on all treatments. The lowest fecundity was observed in D1. Based on the fertility life table, D3 was the most suitable diet for rearing A. sphaleropa, due to the lowest development time (T), the highest finite increasing rate (l), and total viability exceeding 75%.

Efeito de dietas artificiais para a alimentação de adultos de Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae), em laboratório

Adults of Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae) were maintained in cages of transparent PVC without food, with water, and fed with honey solution at 10% and with honey solution at 10% + 25% of beer only with water and without feeding to evaluate their fecundity, longevity and viability of eggs in growth to (25±1°C and 70±10% of RU). The longevity of females and males was longer and number of eggs/female were obtained in the mean substratum composed of honey at 10% (17,75 days, 17,35 days and 14,07 eggs/posture) and honey at 10% + 25% of beer (18,25 days, 18,20 days and 12,71 eggs/posture). The viability of the eggs and the duration of the embryonic period was similar in all the treatments. The mean with honey at 10% + 25% of beer, presented effects similar to the mean composed with honey at 10% regarding to the longevity, fertility and viability of eggs of B. cranaodes. However, due to the lower cost, the diet based only in honey represents the best choice in laboratory for maintenance rearing of this insect.