Characterization of Relative Susceptibility of Wheat Varieties Against Rice Weevil (Sitophilus oryzae Lin.)

An in vitro studied on the relative susceptibility against Sitophilus oryzae (Lin) was carried out in eighteen verities of wheat. The varieties were screened by no choice and free choice test separately and replicated four times. In free choice test hundred pairs of adults were released in each variety. Number of adult oriented in each variety was counted. Significantly minimum number of adult was oriented in variety HUW-552 (3.1) and significantly higher number in variety HD-2285 (13.6). In no choice test five pairs of adults were inoculated in each variety. Adult emergence, total development period and sex ratio were computed. Total developmental period ranged from 32.2 days in DL- 806 to 37.6 day in Lok-1. The number of adult emerged was significantly ranged from 1.7 (Raj-4000) to 12.0 (PBW-468). The sex ratio male (1): female ranged from 0.75 (Raj-4000) to 1.75 (GW-273). The variety Raj-4000 expressed hindrance to orientation and emergence of pest and took a more time for development of Sitophilus oryzae L and therefore found relatively least susceptible. It was followed by HUW-522 and HI-8381. However, HI-8498 showed relatively susceptible response.