浙江稻田稻秆潜蝇为害损失与防治指标研究

2000-2004在浙江较系统地研究了山区和半山区稻田稻秆潜蝇的种群动态与为害损失的关系,组建了田间自然种群生命表。结果表明：自然条件下，1、2代稻秆潜蝇的卵、幼虫、蛹、成虫死亡率分别为42.7%、14.5%、4.4%、12.6%和32.8%、16.5%、18.9%、15.6%。水稻秧苗期、大田期稻秆潜蝇卵（虫）量与株为害率、为害损失率的关系分析表明，随着卵（虫）量增加，株为害率上升，产量损失率加大，两者呈显著正相关。成虫盛发至卵孵盛期为防治适期，稻秆潜蝇防治指标为秧苗期平均每百株有卵10粒，株为害率1%以上；大田期平均每丛水稻有卵1粒，株为害率3%～5%。

Rice yield loss due to Chlorops oryzae Matsumera and its action thresholds in rice fields in Zhejiang province

The population dynamics of Chlorops oryzae and its relationship to rice yield loss in rice fields of mountain and semi-mountain areas in 2000-2004 in Zhejiang province,East China were systematically studied,and the life table of field populations of this pest was constructed.The results showed that the mortalities of egg,larva,pupa and adult of this pest in fields were 42.7%,14.5%,4.4% and 12.6% for the first generation,and 32.8%,16.5%,18.9% and 15.6% for the second generation,respectively.The incidences of injured plants and yield loss were positively related to egg(larva)density in both seedling and after transplanting periods.The time from adult emerging peak to egg hatching peak was proposed as the optimal control period.The control thresholds were determined as 10 eggs per 100 rice plants or 1% injured plants in seedling bed,while 1 egg per hill or 3%-5% injured plants in the paddy after transplanting.