Effects And Mechanisms In Arthropod Community And Enemy Of Transgenic Hybrid Poplar 741 With Two Insect-Resistance

Based On the methods of community ecology and population ecology,composition strcture,nutrition strcture,characteristic community and stability were studied on transgenic insect-resistant hybrid poplar 741(Pb29) and hybrid poplar 741(CK),and effect of Harmonia axyridis(Pa\\as) on transgenic insect-resistant hybrid poplar 741 were studied on arthropod community .The purpose of this study is to accumulate scientific basis for the evealuation of bio-safty of transgenic 741 poplar and to study mechanism of arthropod community on transgenic insect-resistant hybrid poplar 741.The results are as follows:1.Compositive species were similar between Pb29 and CK,main compositive groups were Lepidoptera,Coleoptera,Araneae,Homoptera and Hymenoptera.Numbers of individual and species of Lepidoptera in Pb29 were obviously decreased.On nutrition strcture in arthropod community,function groups on every nutrition level were similar between Pb29 and CK,but in Pb29 leaf-eating pest on bascal species largely decreased,the rate of intermediate species increase ,top species have no obviously changing.From dymanic time of pecies riches and individual numbers,there has similarly changing tendency.It is cleare that composition strcture and nutrition strcture were not negative affected.2.The study on diversity indexes,eveness indexes and dominant value indexes of arthropod community and every sub-community shows that compared with CK, diversity indexes and eveness indexes were higher, dominant value indexes were lower except pest sub-community,but differences were not obvious.The dynamic time on arthropod community and every sub-community has similarly changing tendency. Every characteristic community indexes in Pb29 changed more slowly than indexes of CK which indicated resistance of interference outword increased.From static station to dynamic station of arthropod community and every sub-community were not affected.3.Using the generalized diversity index,the redundancy structure theory,Ss/St andSn/Sp,stability were being analyzed.It was discovered that, the species diversity,the trophic level diversity,the web diversity and the general information diversity were higher than CK;when community of Pb29 were interfered,the species redundancy recruitment,trophic channel redundancy recruitment and the web chains redundancy recruitment timely appear to relieve risk;the value of Ss/St and Sn/Sp were higher thanCK.4.Species riches,individual numbers,eveness,dominant valve and diversity were uses for Path Analysis.The Path Analysis shows that eveness and dominant valve were most closest with diversity arthropod community and every sub-community of Pb29 and CK and individual numbers were not close with diversity which show that increasing diversity index,increasing eveness and decreading dominant values were most important .These results shows that the number of pest decreasing have no influence with diversity which improve eveness and reduce dominant value.5.Laboratory experiments were carried out to study the survival and development of the Harmonia axyridis(?a\las) feeding on Chaito phorus popleti(Panzen) on high insect-resisitance hybrid poplar 741(Pb29) and medium insect-resisitance hybrid poplar 741(Pbl7).The API 741 poplar was used as control.The mortality and development during immature period,adult,baby mass.eclosion and sex ratio of H. axyridis(Pallas) were measured.The results showed that:to contrast The API 741, Chaito phorus popleti(Panzen) on Pbl7 and Pb29 has no significantly impacts on eclosion,pupation, ecdysis,mortality of immature period and pupa stage;Although every development stage of ladybeetles were not affected to ,the pupal duration of ladybeetles was lowered than the control;The body mass,eclosion and sex ratio have no significant difference.The survival curved-line of Harmonia axyridis(Pallas) feeding on Chaito phorus popleti(Panzen) on Pbl7 and Pb29 has the similarily changing tendency.