Demography of date palm fruit stalk borer, Oryctes elegans (Col.: Scarabeaidae), on date palm under laboratory conditions

The date palm fruit stalk borer, Oryctes elegans Prell. (Col.: Scarabeaidae) is a serious pests of date palm in Bam region, Iran. In this research, demographic parameters O. elegans were studied under controlled conditions at 27±2ºC and 65±5% RH and 16:8 L: D. Data were analyzed based on an age-stage, two-sex life table, to take both sexes and variable development into consideration. Developmental time mean for egg, larvae and pupa were obtained 16.4, 216.8 and 26.2 respectively. In the laboratory, 5.2, 22.6 and 3.2% died in the egg, larval and pupal stage, respectively. The intrinsic rate of increase (rm), finite rate of increase (λ), gross reproductive rate (GRR), net reproductive rate (R0), doubling time (DT) and mean generation time (T) were 0.002d-1, 1.002d-1, 71.6 offspring, 42.3 offspring, 110.7d and 328.5d respectively. These facts indicated that O. elegans is a univoltine species.