Comparative demographic parameters of beet armyworm, Spodoptera exigua (Lep.: Noctuidae) on four commercial sugar beet cultivars

Effects of four sugar beet cultivars (Anaconda, Rozier, Evelina and Flores) on the life table parameters of beet armyworm, Spodoptera exigua (Lep.: Noctuidae) were evaluated at 26 ± 1 °C, 60 ± 5% relative humidity and a photoperiod of 16: 8 h (L: D). The highest gross and net fecundity rates were obtained on Anaconda (2573.31 ± 27.78 and 1576.31 ± 16.65 eggs/female, respectively). The net reproductive rate (R0) was the highest on Anaconda (341.38 ± 56.31 female offspring) and the lowest on Flores and Evelina (106.30 ± 22.4 and 144.62 ± 30.81 female offspring), respectively. The intrinsic rate of increase (r) was affected by different sugar beet cultivars, ranging from 0.197 day−1 (on Flores) to 0.274 day−1 (on Anaconda). The highest value of finite rate of increase (λ) was on Anaconda (1.31 day−1). The mean generation time (Tc) was different on the various cultivars, ranging from 21.04 ± 0.60 days (on Anaconda) to 23.68 ± 0.38 days (on Flores). Results on the demographic parameters revealed thatAnaconda was the most suitable host plant among the mentioned sugar-beet cultivars for S. exigua.