Biology of Sylepta derogata (Fabricius, 1775) (Lepidoptera: Crambidae) on Urena lobataa L.

Abstract

Sylepta derogata (Fabricius), a defoliating pest in the family Crambidae, is known for its affinity toward Malvaceae hosts. This study investigates the biology of S. derogata on Urena lobata, a common wild and medicinal plant. Observations on life cycle stages, developmental duration, fecundity, and feeding behavior were made under controlled laboratory conditions. The study revealed that the female moth laid 200-300 eggs. The eggs hatched after an incubation period of 3.55±0.55days. The first instar larva measured 3.95 ± 0.77 mm in length and 0.28 ± 0.03 mm in width with mean duration of 3.4 ± 0.41days. The second instar larva measured 9.34 ± 0.96 mm in length 0.41 ± 0.08 mm in width with duration of 3.7 ± 0.96days, whereas, the third instar larva measured 15.64 ± 0.12 mm in length and 1.06 ± 0.05 mm in width with longevity of 4.61 ± 0.84days. The fourth instar larva measured 19.21 ± 0.48 mm in length and 1.29 ± 0.06 mm in width with duration of 3.41 ± 0.46 days, while the fifth instar larva measured 21.54 ± 1.55 mm in length and 1.94 ± 0.04 mm wide with duration of 2.61 ± 0.6 days. The prepupa was 17.10 ± 0.51 mm in length and 1.86 ± 0.06mm in width with duration of 1.3 ± 0.4 days. The pupa was 16.4 ± 0.51 mm long and 2.52 ± 0.53 mm wide with duration of 8.5 ± 1.23 days. Pre-oviposition, oviposition, and post- oviposition period was recorded 2.65 + 0.85, 2±0.01, and 1.89 ± 0.54 days respectively. Male and female survived for 4.50±0.23and 5.81±0.21days respectively. The life cycle was completed in 31.08±5.47days.