Host cultivar drives demographic trade-offs in Acanthoscelides obtectus (Coleoptera: Chrysomelidae): an age-stage, two-sex life table analysis on dry beans

The bean weevil, Acanthoscelides obtectus , is a major post-harvest pest of dry beans, with host plant traits influencing its population growth. Efficient pest management requires characterisation of how host cultivars regulate pest demography. In this study, we evaluated the life history traits and demographic parameters of A. obtectus on three commercial dry bean cultivars (‘Akın’, ‘Atmaca’, and ‘Berrak’) using age-stage, two-sex life table analysis. Host cultivars significantly altered pre-adult development, survival, and subsequent reproductive values. The incubation period and pupal duration were significantly shorter on ‘Atmaca’, yielding the briefest pre-adult development (34.45 ± 0.09 days) and total pre-oviposition period (35.50 ± 0.13 days). Conversely, ‘Akın’ supported the highest lifetime fecundity (24.86 ± 1.41 eggs/female). Consequently, the net reproductive rate ( R 0 ) was significantly greater on ‘Akın’ (15.54 ± 1.60 offspring/female) than on ‘Berrak’ (10.39 ± 1.15) and ‘Atmaca’ (9.19 ± 0.99), reducing its population doubling time to 10.74 days. Age-stage-specific life expectancy and mortality distributions showed that adult senescence was delayed on ‘Akın’, whereas deaths were clustered early on ‘Atmaca’ and ‘Berrak’. These findings suggest that, based on official seed characteristics, differences among host cultivars drive the evolutionary trade-offs between pest development and reproduction. Specifically, while ‘Atmaca’ promotes rapid population turnover through accelerated pre-adult development, ‘Akın’ favours long-term population growth via superior reproduction. Ultimately, incorporating these cultivar-specific demographic insights can enhance sustainable storage preservation of dry beans by guiding cultivar selection and targeted control measures.