Biology and life table study of Spilarctia obliqua Walker (Arctiidae: Lepidoptera) on different bast fibre crops

The influence of different bast fibre crops i.e. jute (Corchorus olitorius and C. capsularis), mesta (Hibiscussabdariffa and H. cannabinus), ramie (Boehmeria nivea) and sunnhemp (Crotalaria juncea) on biology and life table parameters of jute hairy caterpillar, Spilarctia obliqua Walker was carried out to understand the host suitability under laboratory condition. Adult longevity and fecundity of S. obliqua and its life table parameters were differed significantly with bast fibre crops. The larval, pupal period and adult longevity of S. obliqua were shortest on C. olitorius and longest on H. sabdariffa. The larval survival and adult fecundity (eggs/female) significantly highest (80.68 ± 1.41%, 477.00 ± 21.12 eggs) in C. olitorius and the lowest (53.92 ± 1.20%, 260.00 ± 21.41 eggs) was on H. sabdariffa, respectively. The net reproductive rate was higher on C. olitorius (384.84 ± 21.56 females/female/generation) and minimum (163.80 ± 14.65 females/female/generation) on H. sabdariffa. The intrinsic rate of natural increase was higher on C. olitorius (0.15 ± 0.00 females/female/day) and lowest (0.12 ± 0.00 females/female/day) on H. cannabinus. The study indicated that C. olitorius was the most suitable host as compared to other crops for S. obliqua growth and reproduction.