Yield Loss in Two Rice Cultivars by the Small Rice Grasshopper, Oxya nitidula (Walker)

Present investigation aimed at evaluating the yield loss of two rice cultivars CO43 and CO45 by the small rice grasshopper Oxya nitidula (Walker). Three different growth stages of the cultivars were selected 31 days after sowing (DAS), 46 DAS, and 61 DAS for evaluating the damage potential by the small rice grasshopper. Infestation was carried out at different population level, 2 insects/cage, 4 insects/cage, 6 insects/ cage and 8 insects/cage. Damage caused by the insects was directly related to the grains harvested on the two rice cultivars. The result suggests that grain loss increased with increasing number of insects infesting the plant. At 31 DAS treatment damage was more, compared to other DAS treatments.