BIOLOGY OF RICE HISPA, DICLADISPA ARMIGERA (OLIVIER) (COLEOPTERA: CHRYSOMELIDAE)

Biology of rice hispa, Dicladispa armigera (Olivier) was carried out under laboratory conditions at room temperature varying between 32.98 to 23.67 °C, with a relative humidity 92.86 to 84.61 per cent. The adult beetle was shiny bluish black having short spines all over the body with fecundity of 81.2±8.83 eggs per female. Incubation period was 5.03±0.02 days with hatching 73.98±1.94 per cent. There were four larval instars and total larval period was 13.05±0.23 days (11-14 days) with 85.00 per cent survival.  The average pupal period was 7.05±0.21 days. The adult male was short lived 25.10±3.02 days as compared to female 34.70±1.81 days. The egg was 1.00±0.005 mm in length and 0.45±0.006 mm in width. The larva increased in body size with age as 1.43±0.51-2.62±0.007 mm in body length, 0.31±0.008-0.50±0.005 mm in body width and 0.06±0.003-0.09±0.002 mm in length of cerci of first and fourth instar larva, respectively. The overall sex ratio of male to female was 1:1.26.