Biological and reproductive aspects of Piezodorus guildinii (West.) (Hemiptera: Pentatomidae) under laboratory conditions

Abstract

Aspects of the life cycle, reproduction and mortality of Piezodorus guildinii (Westwood) were evaluated under laboratory conditions: temperature = 24.9 ± 0.5 °C; relative humidity = 53.6 ± 7.9 % and 16-hour photophase. Insects were fed with fresh fruits of Phaseolus vulgaris (L.). Survival and fecundity were calculated, and the following population parameters were estimated: net reproductive rate (R₀), generation time (T), intrinsic rate of natural increase (r), finite rate of increase (λ), and reproductive value (Vₓ). Mean time from oviposition to adult was 32 days. Nymphal mortality was 60.1 %, with the highest values in the second nymphal instar. Adult longevity was 60 and 78.5 days in males and females, respectively, without significant differences (p > 0.05) between sexes; the sex ratio was 1.3 females : 1 male. Mean number of eggs per female was 86.33; each female laid 8.5 egg masses with an average of 9.5 eggs per mass. Other results were: R₀ = 7.45 females/female in a generation; T = 88.3 days; r = 0.023 and λ = 1.02 individuals/female. The greatest reproductive value was recorded during the 9th week.