有机稻田埂植物上节肢动物多样性

Arthropod diversity on plants at field margins of organic farming paddy rice

对稻鸭共作有机稻和常规稻田埂杂草、大豆和芝麻上的节肢动物群落进行了全季节系统调查,共采集2纲、12目、76科、172种,其中天敌103种(包括33种蜘蛛,6种捕食性昆虫和64种寄生性昆虫)、植食性昆虫64种。结果表明,蜘蛛和天敌昆虫丰富度以有机稻田埂最大,其蜘蛛物种数和个体数是常规田埂的4.5倍以上,天敌昆虫物种数和个体数是常规田埂的1.5倍以上。比较田埂植物上昆虫多样性表明,在有机稻田,大豆和杂草田埂上的昆虫物种丰富度最大(71),其次是芝麻(62),而杂草上的Shannon多样性指数最大;在常规稻田,大豆田埂上昆虫丰富度(52)和Shannon多样性指数最大,杂草上的昆虫Shan-non多样性指数最小。有机田埂杂草上蜘蛛和飞虱发生动态有明显的跟随现象,由于喷施杀虫剂防治飞虱,常规田埂杂草上的蜘蛛和飞虱数量都处于较低水平,且没有明显的跟随现象。调查结果说明,有机稻田比常规稻田更有利于天敌的保护,在常规管理模式下田埂种植大豆和芝麻对稻田节肢动物群落保护具有积极作用。

An investigation was conducted on the arthropod community on the plants（weeds,soybean,and sesame） at the margins of both organic farming paddy rice-duck field and conventional paddy field with wheat-rice rotation in East China across rice growth season.A total of 172 arthropod species belonging to 76 families,12 orders,and 2 classes were collected,including 103 species of natural enemies（33 spiders,6 predatory insects,and 64 parasitoid species） and 64 species of phytophagous insects.At the margins of organic farming paddy rice-duck field,the species richness and abundance of the spiders and insect natural enemies on the plants were 4.5 times and 1.5 times greater than those at the margins of conventional paddy field,respectively.The insect species richness at the margins of organic farming paddy rice-duck field was the highest on soybean and weeds（71）,followed by on sesame（62）,and the Shannon index was the highest on weeds;while at conventional paddy field margins,the insects on soybean had the highest richness（52） and Shannon index,and those on weeds had the smallest Shannon index.An obvious link was observed in the seasonal variations of the abundance between spiders and rice planthoppers on the weeds at organic farming paddy rice-duck field margins,but not observed at conventional paddy field margins probably due to the application of pesticides for the control of rice planthoppers.This investigation indicated that,compared with conventional paddy field,organic farming paddy rice-duck field was more beneficial to the protection of natural enemies,and planting soybean and sesame at conventional paddy field margins had positive effects on the conservation of arthropod community in paddy field.