Diversity and abundance of insect pests in stored rice under two agro-climatic zones of West Bengal and Tripura

Five insect species consisting off four colepteran pests viz., Rice weevil, Sitophilus oryzae (L.), Redflour beetle, Tribolium casteneum (Herbst, 1797), Sawtoothed beetle, Oryzaephilus surinamensis (L.), Flat grain beetle, Cryptolestes pusillus (Schonherr, 1817) and one hymenopteran parasitoid, Anisopteromalus calandrae (Howard) were recorded from stored rice grains in both the agro-climatic zones. Sitophilus oryzae emerged as the dominant insect species of rice followed by Tribolium castaneum in all four locations (viz. Pundibari, Coochbehar and Chopra under Terai zone of West Bengal and Ranir Bazar under eastern humid zone of Tripura). Maximum population of the parasitoid was observed in eastern humid zone of Tripura whereas it was absent in Chopra under terai zone of West Bengal.