| Two transgenic rice lines with high resistance to stem borer, [Bt rice (KMD1) and crylAb + sck rice (MSB)], three herbivores including two serious pests [stripped stem borer (SSB) Chilo suppressalis and brown planthopper (BPH) Nilaparvata lugens], one occasional pest [Mycalesis gotama] and three important natural enemies [Apanteles chilonis, Microvrlia horvathi, Pirata subpiraticus] were selected to study effects of transgenic rice lines on biological characteristics of the natural enemies through food chain and the relevant possible mechanisms in the laboratory. The main results were summarized as follows.1. Effects of transgenic Bt rice on survival and growth of SSB and biological characteristics of Apanteles chilonis via SSBThe corrected mortalities of 3rd, 4th and 5th instar larva of SSB continuously fed on KMD1 increased to 90.1%% 80.3% and 45.7% on the 4th day, respectively. The corrected mortalities of 3rd and 4th instar larva were 100% on the 6* and 7th day respectively, while that of 5th instar larva reached 96% on 8th day. Corrected mortality of SSB fed on control rice after fed on KMD1 for different times increased with feeding time on KMD1.The body weights of SSB fed on control rice after feeding on KMD1 for 36 h were very significantly lower on day 0 and day 3, and significantly lower on day 9, compared with those of the control.Parasitism rates of host larvae fed on KMD1 by Apanteles chilonis were significantly (3rd instar) or very significantly (4th and 5th instar) lower than those of the control host. Percentages of cocoon formation for 3rd and 4th instar hosts fed on KMD1 significantly declined. Pupa period of the parasitoid from the 3rd instar larva fed with KMD1 was significantly shorter, compared with the control. Longevity of the male wasps from the fifth instar larva fed on KMD1 was significantly shorter. Length of wasp cocoon of KMD1 treatment was significantly shorter. But no significant differences were detected in the development periods of egg to larva, cocoon mass size, wasp emergence rate and sex ratio between KMD1 and the control.2. Effects of transgenic cry 1 Ac + sck rice on survival and growth of SSB and biological characteristics of Apanteles chilonis via SSBMortality of SSB continuously feeding on MSB increased steadily, and was very significantly higher than that of MH 86 control on day 6 and afterwards. The weight of SSB continuously feeding on MSB was also significantly less than that of control on day 2 and afterwards.Mortalitis of SSB feeding on the control for 0 h 24 h 48 h 72 h after feeding on MSB for 36 h were all higher than those of the control, but the differences were not significantly. However, the weights of SSB were all very significantly less than those of the control.Mortalitis of SSB feeding on the control for 3 6 9 12 days after feeding on MSB for 36 h were higher than those of the control without significant differences; But the weights of the SSB were all lessthan those of the control, very significantly or significantly on day 3 and 6, respectively.Parasitism rates of host larvae fed on MSB were lower than those of the control, but only significantly for 4th instar. There were no significant differences for percentage of pupa formation between treatment and control. Development period of the parasitoid pupa from the 5th instar larva fed on MSB was significantly longer. Length of cocoon of MSB treatment was significantly shorter than the control. However, no obvious differences were detected in the development periods of egg to larva, cocoon mass size, wasp emergence rate, sex ratio, longevity and forewing length of wasp between KMD1 and the control.3. Amino acid content in the haemolymph of SSB after fed with transgenic riceAlthough there were no changes on the components of amino acids in the haemolymph of SSB after fed with two transgenic rice lines, there were some changes on relative contents of amino acids. Contents of total amino acids as well as His, Gly, Phe, He, Lys, Gin and Pro in haemolymph of SSB on...
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