The life table parameters of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) reared on nine rainfed barley cultivars

Abstract

The lesser grain borer, Rhyzopertha dominica (F.) attacks various cereals and causes serious damage during storage periods in many parts of the world including Iran. In this study, the impacts of nine rainfed barley cultivars namely Abidar, Ansar, Izeh, Fardan, Khoram, Mahoor, Nader, Nimroz, and Sararod were determined on the life table parameters of R. dominica in the laboratory, at 25 ± 2 °C, 60 ± 5% RH, and darkness, using the age-stage, two-sex life table theory. The different life table parameters of R. dominica were significantly influenced by tested cultivars. The incubation period of R. dominica was longest on Ansar (7.55 d) and shortest on Izeh (6.53 d). Among tested cultivars, developmental time of R. dominica immature stages was longest on Ansar (47.94 d) and shortest on Fardan (45.43 d). The total female life span for insects reared on Ansar (115.82 d) was significantly longer than other cultivars. The highest and lowest fecundities observed fed on Ansar (148.21 eggs) and Nader (81.78 eggs), respectively. Life expectancy (exj) for all stages of individuals reared on Ansar was highest compared to other cultivars. The intrinsic rate of increase (r) differed among tested cultivars and was significantly lowest on Mahoor (0.052 day−1) in comparison to other cultivars. The cluster analysis results indicated that Sararod, Nader, Nimroz, and Mahoor are relatively resistant cultivars for R. dominica performance and can be used in the integrated pest management program for this pest.