【作者】 刘志诚；

【导师】 胡萃；

【作者基本信息】 浙江大学 ， 农业昆虫与害虫防治， 2002， 博士

【摘要】 针对转基因抗虫作物的生物安全性在全球范围内倍受关注的现状，本文以转Bt基因抗虫籼、粳稻的四个品系，即转cry1Ab／cry1Ac杂合基因籼稻的TT9-3、TT9-4，转cry1Ab基因粳稻的KMD1、KMD2为材料，通过室内和田间研究，对其释放到环境后的生态风险进行了系列评价。结果如下： 1 Bt水稻对稻田节肢动物群落结构的影响 Bt水稻稻田生境中，节肢动物各功能团优势类群组成与对照基本相同：植食性昆虫优势类群为飞虱和叶蝉；寄生性昆虫为茧蜂和金小蜂；捕食性天敌包括捕食性昆虫盲蝽、舞虻或长足虻，以及蜘蛛类的肖蛸、皿蛛和狼蛛；腐食性昆虫为鳞跳虫和圆跳虫。寄生性昆虫的总优势度虽多低于对照，但差异未达显著水平。Bt水稻田中节肢动物群落的物种丰富度、Shannon-Winner多样性指数、均匀性指数和优势集中性指数，及其时间动态，与对照相比基本上无明显差异。Bt水稻田与对照间节肢动物群落相似程度高。可见，Bt水稻对节肢动物群落结构一般无明显的负面影响。 2 Bt水稻对非靶标害虫亚群落结构及其优势类群数量动态的影响 Bt水稻与对照间相比，非靶标植食性昆虫类群组成相似，其中飞虱和叶蝉均为重要的优势类群。非靶标植食性昆虫总个体数、各类群优势度分布、优势类群如飞虱、叶蝉的总个体数和密度时间动态，以及白背飞虱、灰飞虱和黑尾叶蝉种群密度时间动态则因转基因水稻品系、年份、地点而异，与对照相比一般多无显著差异，但有时显著，甚至极显著以转基因水稻为高或为低。可见，Bt水稻对非靶标植食性昆虫尤其是优势类群或种类的总数量和密度有时会呈现一定负面或正面效应。 3 Bt水稻对寄生蜂亚群落结构及其优势类群数量动态的影响 Bt水稻稻田生境中，寄生蜂类群的组成与优势度总体分布与对照间无显著差异，但个体总数和田间密度因寄生蜂类群不同而异，靶标害虫寄生蜂如茧蜂或姬蜂一般少于，有时甚至显著低于对照，而非靶标害虫寄生蜂与对照间大多无明显差异。 4 8t水稻对捕食性昆虫亚群落结构及其优势类群数量动态的影响 虽然转cry1Ab基因粳稻与对照间捕食性昆虫优势度分布有差异，但就稻田捕食性昆虫个体总数及亚群落总密度时间动态，黑肩绿盲蝽、姬蝽、舞虻和长足虻的个体总数及 种群密度的时间动态而言，两类Bt水稻与对照相比，大多情况下都无显著差异，有时 甚至以前者明显为高。可见，Bt水稻对稻田优势捕食性昆虫的组成与丰盛度无明显负作 用，甚至有时具有一定的正效应。：5 Bt水稻对蜘蛛亚群落结构及优势种数量动态的影响 蜘蛛种类组成及优势种在两类转基因Bt水稻田与对照间基本相同，但转CrylAb基 因粳稻田个体数均少于甚至显著少于对照。转CrylAb止rylAC基因釉稻田蜘蛛亚群落的 物种丰富度、Shannon－Wuuer多样性指数、均匀性指数和优势集中性指数与对照间无明 显差异。而转err1Ab基因粳稻田的物种丰富度、多样性指数、均匀性指数均低于对照， 优势集中性高于对照。三种优势种，即锥腹肖峭、食虫沟瘤蛛和拟水狼蛛的种群密度与 对照间大多无显著差异。 6 Bt水稻对蜘蛛生境选择性的垢响 用陷阶法对蜘蛛在转CrylAb七rylAC基因釉稻稻田与对照间相互迁移的监测结果表 明，在水稻生长季节始终有一定数量的蜘蛛相互迁移，且以拟环纹豹蛛和拟水狼蛛为优 势种，两种稻田个体总数无显著差异。就两者间若蛛和成蛛总迁移数量，以及拟环豹蛛 和拟水狼蛛的迁移量而言，在大多时间内均无显著差异。可见，地面游猎蜘蛛在Bt水 稻稻田生境和对照间选择时，未表现出明显的偏嗜性。 7 Bt水稻对拟水狼蛛捕食作用的间接影响 室内研究了拟水狼蛛对取食转CrylAb／crylAC基因舢稻和转CrylAb基因粳稻的稻纵 卷叶螟幼虫和褐飞虱若虫的捕食量及功能反应。拟水狼蛛对这2种猎物的捕食功能反应 均符合 Holling 11型圆盘方程。该蜘蛛对取食转基因水稻的稻纵卷叶螟幼虫的捕食量和 处理时间与对照差异未达显著水平，而取食转CrylAb基因粳稻上的稻纵卷叶螟瞬时攻 击率显著低于对照。该蜘蛛对以转基因水稻为食的褐飞虱若虫的捕食量、瞬时攻击率和 处理时间与取食对照的相比有一定的变化，但差异均不显著。综合考虑，认为转基因水＿稻对拟水狼蛛捕食作用无明显的负作用。广 8 Bt水稻对H种蜘蛛生长发育与繁殖的间接影响 室内研究表明，以Bt水稻为食的褐飞虱对食虫沟瘤蛛的存活、生长发育、繁殖均无 明显影响。Bt水稻上的稻纵卷叶螟对拟水狼蛛高龄若蛛的存活、生长发育、繁殖影响因 Bt品系而异。转CIylAb止rylACtth稻对其存活、发育历期、繁殖均无明显影响；而转CrylAb 、／更多还原

【Abstract】 Facing to the fact that biosafety of transgenic insect-resistant plant is having become a focus in the world, a series of laboratory and field studies using four transgenic Bt rice homogenous lines, i.e. TT9-3 and TT9-4 with a hybrid gene of cry] Ab / cry 1 Ac, which are indica rice with their parental control cultivar 1R72, as well as KMD1 and KMD2 with crylAb gene, which arejaponica rice with their parental control cultivar Xiushui 11, were carried out to evaluate the ecological risk of transgenic rice released in the environment. The result are as follows:1 Impact of Bt Rice on Arthropod Community Structure in Rice Paddy HabitatThe dominant group compositions of arthropod guilds were almost the same between Bt rice paddy habitats and their control. Both for Bt rice and the control, planthoppers and leafhoppers, braconids and pteromalids, and sminthurids and tomocerids were the dominators among non-target herbivores of Bt rice, parasitoids and detritivores, respectively. As to the predators, the dominators were the insect predators including capsid bugs, and longlegged flies or empidids, and spiders including tetragnathids, linyphiid and wolf spiders. The abundance of parasitoids in Bt rice was apparently lower than the control, while no significant difference (.P>0.05) was found. As to arthropod community structure parameters such as species richness, Shannon-Winner diversity index, evenness index, dominant index and their dynamics in rice paddy habitat, there were no marked difference between Bt rice and the control. The arthropod community structure in Bt rice paddy habitat was very similar to the control.Fn general, Bt rice was no markedly negative effect on arthropod community structure in rice paddy habitat.2 Impact of Bt rice on Sub-community Structure and the Dominator Population Dynamics of Bt rice Non-target Herbivores in Rice Paddy HabitatThe species composition of non-target herbivores sub-community in Bt rice paddy habitat was similar to the control, in which planthoppers and leafhoppers were the dominant groups. The differences in the whole individual number of non-target herbivores, the dominance distribution of each group, total individual number and population density dynamics of dominant groups such as planthoppers and leafhoppers, and the population density dynamics of Sogalella furcifera, Laodelphax striatellus and Nephotettix cincticeps varied with the lines of Bt rice, the tested year and the tested place between in Btrice fields and the control. In general, the differences were not significant, while very clear in some cases. In theses cases, the individual number and population density for Bt rice were significantly higher or lower. According to theses results, it was clear that Bt rice sometime could perform negative or positive effects on the whole individual number and population density of non-target herbivores, particularly for the dominant groups or species.3 Impact of Bt rice on Sub-community Structure and the Dominator Population Dynamics of Parasitoid Wasps in Rice Paddy HabitatIn contrast to the control, the family composition of parasitoid wasps and their dominance distribution were not significant different in Bt rice fields. While the differences in the individual number and population density between Bt rice and the control varied with parasitoid groups. In general, the individual number and population density of parasitoid wasps using target insect pests of Bt rice as hosts, including braconids and ichneumons, were less or lower in Bt rice fields than the control, and even the differences between Bt rice and the control reached the stastically significant levels. In contrast, the difference between Bt rice and the control did not encounter to the parasitoid wasps using non-target insect pests of Bt rice.4 Impact of Bt rice on Sub-community Structure and the Dominator Population Dynamics of Insect Predators in Rice Paddy HabitatFor total individual number and total density dynamics of insect predators, total individual numbe更多还原