Developmental and Reproductive Biology of Brinjal Shoot and Fruit Borer (Leucinodes orbonalis, Guenee) in Brinjal (Solanum melongena L.) under the Lab Conditions

The developmental and reproductive biology of the brinjal shoot and fruit borer, Leucinodes orbonalis Guenée (Lepidoptera: Crambidae), was investigated under laboratory conditions using insects cultured from infested brinjal fruits of the Pusa Purple Round variety. Eggs from the subsequent laboratory generation were used to record incubation, hatchability, successive larval instars, pre-pupal and pupal durations, adult longevity, reproductive periods, fecundity and sex ratio. Observations were summarised as means ± standard deviations and observed ranges. Incubation lasted 3–5 days (3.84 ± 0.26days), and egg hatchability ranged from 70% to 80% (76.4± 4.90%). Five larval instars were identified, with a combined larval duration of 13.20–15.20 days (14.36 ± 0.68 days). Mean pre-pupal and pupal durations were1.68 ± 0.30 and 9.52 ± 0.52 days, respectively. Development from egg to adult emergence required 26.60–31.00 days (29.40 ± 1.67days). Adult males survived for 3.6 ± 0.89 days, compared with 5.80 ± 1.30 days for females. Pre-oviposition, oviposition and post-oviposition periods averaged 1.40 ± 0.20, 3.16 ± 0.17, and 1.24 ± 0.09 days, respectively. Female fecundity averaged 188.08 ±8.81 eggs, and the male-to-female sex ratio was 1:2. These findings describe stage-specific development and reproduction under the conditions examined and provide a laboratory baseline for subsequent studies of this pest.