Developmental Biology of the Flea Beetle, Podagrica uniforma (Jacoby) [Coleoptera: ChrysomelidaeJ, on Okra, Abelmoschus esculentus (L.) Moench.

Abstract

The developmental biology of the okra flea beetle. Podagrica uniforma (Jac.), was studied in the laboratory under ambient conditions (24-28°C, 79-92 % RH: 12 hour photoperiod) and the various life cycle stages were described. Females laid 159 ± 33.6 eggs over 40.20 ± 8.3 days. The pre-oviposition period was 8.4 ± 1.5 days and the post-oviposition period was 5.1 ± 2.6 days. The eggs were creamy and elliptical, 0.08 ± 0.01 mm in length and 0.03 ± 0.03 mm in width. Larvae were oligopod and elongate with off-white thoracic and abdominal regions and brown head and anal disc. The head-capsule width of the 1st, 2nd and 3rd instars averaged 0.20,0.30 and 0.43 mrn, respectively. Average growth rate for the three larval instars was 1.49. There was a high significant correlation (r = 0.997: P = 0.05).between the mean width of the head-capsules and elapsed developmental period. The pre-pupa was a non-feeding, sluggish larval stage. The means of pre-pupal length and width were 3.6mm and 0.7mm. Pupa was exarate, off-white, and looked like a mummified adult. Pupal length and width averaged 2.9 mm and 1.1 mm, respectively. Sex ratio was 1.5: 1. The head, thorax and elytra of adult were golden brown. Females were significantly larger than males (P= 0.05).