Evaluation on the paddy dwelling chironomids in view of IPM

1)世界稻田摇蚊种类共记录158种，隶属于摇蚊科3亚科49属。2)稻田摇蚊的发育研究：对稻田摇蚊幼虫的龄期、幼虫发育、总有效温度、发育历期、成虫的羽化节律、成虫寿命、卵子数、性比等进行了研究，获得了相关数据。3)稻田的种群密度采用系统抽样的方法对稻田发生的摇蚊种群进行了估算。据估计，在3个月内，每棵水稻(691m^2)的产量为414万英镑。同一稻田65天的幼虫密度估计为413万头，从抽样方法等原因来看，估计偏低。4)在不同基质含水率条件下，测定了不同基质含水率条件下的末龄幼虫的抗旱性。5)摇蚊幼虫捕食性昆虫共观察到蜻蜓6种，半翅目-异翅目4种，鞘翅目6种，其中13种为水生捕食性摇蚊幼虫。

1) Chironomid species recorded from paddy fields in the worldA total of 158 species belonging to 3 subfamilies and 49 genera of the Chironomidae were recorded from the world paddy fields up to present. The insect group is the most diverse and dominant in the paddy field ecosystem.2)Development of chironomidsLarval instars, larval development, total effective temperature, developmental period, emergence rhythm of adults, adult longevity, number of ovarian eggs, sex ratio of Tanytarsus oyamai Sasa and Glyptotendipes tokunagai Sasa were studied and the data concerned were obtained.3)Population density in paddy fieldsAdult chironomid populations occurring in paddy fields were estimated by systematic samplings using emergence traps. It was estimated as 4.14 million in a paddy (691 m^2) during 3 months. It was about 6, 000/m^2. Larval density in the same paddy was estimated as 4.13 million during 65 days, and it seemed to be under estimated judging from the sampling method and other reasons.4)Drought resistance of larvaeDrought resistance of the last instar larvae of Glyptotendipes tokunagai was tested by rearings under different water content of media. Drying media allowed the larvae alive for 30 - 50 days until the water content decreased to 30%.5)Predeaceous insects of chironomid larvaeA total of 16 species belonging to Odonata (6 species), Hemiptera-Heteroptera (4 species) and Coleoptera (6 species) were observed as aquatic predatory species of chironomid larvae.Thirteen species among them were reared to find their feeding habit especially the number of chironomid larvae eaten for food.