Influences Of Bt Rice On Arthropod Community In Rice Field

The difference of arthropod community between KMD (transgenic rice containing a synthetic crylAb gene from Bacillus thuringiensis Berliner, Bt) and its parent XS11 (control) was investigated in the single rice-cropping season in 2000 in Hangzhou. The main results showed as follows:1. The arthropod communities in the two paddy plots were similar, although the abundance and species richness in the KMD plot were little higher than those in XS11 plot.2. The KMD was high resistant to the larvae of Lepidoptera. More adults were caught by Malise Trap at KMD side, which indicated the adults in KMD plot prepared to leave the plot.3. The abundance of insect pests in the KMD plot was higher than that in XS11 plot, because of the higher populations of the white-backed planthopper(WBPH), Sogatella furcifera and the green rice leafhopper, Nephotettix cincticeps in the KMD plot. The abundance of natural enemies in the KMD plot was also higher than that in the XS 11 plot. But the abundance of neutral insect in KMD plot was less than that in XS11 plot.4. The abundances of Hemiptera, such as Microvelia horvathi; Cyrtorrhinus lividipennis and one species of Nabidae, in the KMD plot were higher than those in the XS11 plot, especially in the middle term of the crop season, due to of the higher abundance of their prey (WBPH) in the KMD plot.5. The appearing time of Braconidae in the KMD plot was later than that in the XS 11 plot, but the abundance of egg parasitoids of the planthoppers in KMD field was higher than that in the XS11 plot. Therefore, the abundance and species richness of Hymenoptera in the KMD plot was lower in the early half-season, but higher in the late half-seasoncompared with those in the XS11 plot.6. The spider species richness in two plots was similar. Although the abundance of spiders in the XS11 plot was higher than that in the KMD plot, there is no significant difference of the spider abundance between the two plots.7. The abundance of Diptera was higher during the first month of the rice cropping season. The abundance of Diptera in the KMD plot was higher than that in the XS11 plot, but the species richness of Diptera in the two plots was similar. The abundance of Sminthuridae in the XS11 plot was higher than that in the KMD plot during the first month after transplanting.