Effects of Chitanase and Glucanase Transgenic Rice on Three Species of Soil Collembola and One Species of Annelida

Effects of transgenic rice with simultaneously constitutive expression of chitinase (RCH10) and glucanase (Glu) on soil collembolan Folsomia candida,Folsomia fimetaria and Sinella curviseta,and enchytraedes Enchytraeus crypticus were studied.Both transgenic and non-transgenic materials of fresh seedling or dry mature rice were used in three experimental systems:Petri dishes,soil-litter microcosms for single species tests and soil-litter mesocosms for multispecies tests.The results showed:1)After 21 day exposure to the seeding materials in Petri dishes,the reproduction of F.candida fed with transgenic leaves and roots was significantly reduced by 45.5% (P<0.05) and 30.5% (P<0.05),respectively,compared to the control non-transgenic wild rice seedlings;2)After 21 day exposure in soil-litter microcosms,there was a weak reduction by 19.3% (P<0.05) of the reproduction of F.candida by transgenic mature dried residues in amounts corresponding to 30 g plant material kg-1 soil;3)After 16 week incubation in soil-litter mesocosms,the reproduction of F.candida was significantly reduced by 19.4% by transgenic rice residues corresponding to the concentration of 30 g/kg soil;likewise,the reproduction of enchytrade E.crypticus was significantly reduced by 38.0%.On the contrary,however,the reproduction of S.curviseta was significantly increased by 84.8%.As for the pesticide positive control experiment,reproduction of F.candida was reduced linearly with concentration of the pesticide.Consequently,the transgenic rice influences reproduction or density of both soil Collembola and enchytraedes,but with decreasing for some species while increasing for other species in density.