Estudo dos Imaturos de Oebalus ypsilongriseus (De Geer, 1773): III - Duração e Mortalidade dos Estágios de Ovo e Ninfa (Heteroptera: Pentatomidae)

The biology of the nymphs of Oebalus ypsilongriseus (De Geer, 1773), a common rice stink bug in Brazil, was studied. Laboratory studies were carried out under constant conditions of temperature (25 ± 1°C), relative humidity (75 ± 10%), and photophase (14 hours); nymphs were reared with inflorescences of Polygonum punctatum Elliot. The duration (in days) and percentage of mortality of immature stages were as follows: egg: 4.7 ± 0.4; 7.2; first nymphal instar: 2.3 ± 0.4; zero; second instar: 4.4 ± 0.8; 6.1; third instar: 3.5 ± 0.8; 2.3; fourth instar: 4.1 ± 0.8; 1.2; fifth instar: 6.7 ± 1.2; 15.2. The sex-ratio was 0.42 (0.7 male: 1 female). It was observed cannibalism on eggs and fifth instar.