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The effects of transgenic Cry1Ab/Cry1Ac rice (Huahui 1) and its original parent (Minghui 63) the on the growth and development of indian meal moth during storage were studied. The results showed that,transgenic rice with Cry1Ab/Cry1Ac gene has a strong lethal effect on the youth larvae (1st to 3rd instars).Temperature has a significant effect on the development duration and speed of each stage of indian meal moth, and the development period was significantly prolonged after being fed with 2% transgenic brown rice meal. The nonlinear model of temperature-dependent developmental rate showed that the developmental threshold temperature of indian meal moth was 7.40 ℃ to 15.94 ℃, while those fed with 2% transgenic brown rice meal was 4.90 ℃ to 17.36 ℃. Our research can deepen the understanding of ecological safety of Bt transgenic rice in theory, and provide theoretical support for scientific development and utilization of Bt transgenic rice in practice.

Transgenic cry1Ab/cry1Ac rice (Huahui 1) is able to control the stored pest Plodia interpunctella.Our previous study confirmed that the enzymatic activities of three major antioxidases, including POD, CAT,and SOD, could be significantly changed after short-term stressed with these Bt containing rice. This study focused on the characteristics of rice during storage, the results showed that the Bt protein content in rice husk and brown rice was 5.534 μg/g and 1.003 μg/g respectively, and after 270 days at 25 ℃, the degradation rate was 67.3% and 27.7%, respectively. Moreover, the enzymatic activities of three antioxidases in P.interpunctella long-term fed with transgenic cry1Ab/cry1Ac rice powder would be addressed by enzymatic detection assays. Our data showed that the SOD activities could be significantly inhibited by the Bt containing rice after fed with Bt-rice powder for 12 days or 5 months, However, the enzymatic activities of POD and CAT significantly increase with the concentrations of Bt toxins. In addition, the change trend of protective enzyme activity in the Indian Meal Moth fed with transgenic rice flour for 5 months was consistent with that after 12 days of feeding. Our researches find that there are differences in the trend of increase and decrease of the three major protective enzymes after fed with Bt containing rice powder for a long time,which indicates that the expression mechanisms of the three protective enzymes might be different. Our results provide a theoretical basis for the study of toxicology and related resistance mechanism of transgenic Bt crops.

The Cry1Ab/Cry1Ac transgenic crops can effectively control pests. In the present study, the world-wide distribute pest, Indian meal moth Plodia interpunctella (Hübener), was taken as the research object. The genes closely related to Bt toxin protein were sequenced using a high-throughput sequencing to reveal the insecticidal mechanism of Bt transgenic rice. The results showed that the de novo assembly generated a total of 37,246 unigenes among of which 23,310 unigenes could be annotated after the transcriptome sequencing was performed on the non stressed population and Bt transgenic rice meal stressed population of Indian rice borer, respectively. Then, 34,466 significantly differentially expressed genes including 15,741 up-regulated genes and 18,725 down-regulated genes were determined by the Reads Per kb per Million reads (RPKM) method. Our database provides powerful tools for transcriptome analysis of P.interpunctella and further understanding of the molecular basis of Bt related mechanisms in P. interpunctella.