Development Of Insect-Resistant Transgenic Japonica With Bt Gene (Cry2A~* And Cry1C~*)

Rice is one of the most important food crop, and the staple food for more than half of the people in the world. Lepidopteran pests are major pests in rice that cause severe yield loss in rice-producing seasons. Plant transgenic technology provides a new way to cultivate high insect resistant rice varieties.Agrobacterium-mediated transformation of cy2A* into Zhendao88, cultivated in Huanghuai area, produced 92 To families independently transformed plants,30 of which was confirmed having one single-copy exogenous gene via Southern blotting, with 29 of them follow Mendelian segregation. crylC* was transformed into Shendao13 and 102 To plants were obtained,31 of which had a single-copy exogenousgene with 29 of them follow Mendelian segregation. Five plants with homozygous genotype of cry2A* and six plants with homozygous genotype of cry1C* were obtained. On tillering stage, Bt protein concentration was measured by EL1SA and the results revealed its varied considerably among 11 different transgenic lines. Field test showed genetically modified plants had admirable resistance to snout moth’s larva and good agronomic performance which testified the two exogenous genes had little impact on the growing development of rice. Meanwhile, the exogenous gene inherited steadily without gene silencing phenomenon. The flanking sequences of cry2A* and cry1C* insert loci were observed via Tail-PCR. The results displayed that cry2A* and cry1C* genes were inserted into rice genome without disturbing any functional genes.Backcross transformation was performed using Indica rice TT51 with exogenous insect-resistant genes crylAb/1Ac*, T2A-1 with cry2A* and T1C-19 with cry1C* in Minghui63 background and Japonica rice RJ-5 with crylC* in Zhonghuall background as donor parents and main cultivars in Huanghuai area Shengdaol3, Shengdaol5 and Zhendao88 as acceptor parents. Ten highly insect-resitant lines including three with cry1Ab/1 Ac from TT51, two with cry2A* from T2A-1, three with cry1(* from TIC-19 and two with cry1C* from RJ-5 were selected based on Basta detection. PCR identification and field insect-resistance selection.In this study, insect-resistant transgenic rice with remarkable resistance to lepidoptera pests was obtained, which provided a good source of resistance to lepidoptera pests for rice varietal improvement. The donor parent insect-resistant material TT51 used here had obtained a security certificate promulgated by the Ministry of agriculture. T2A-1 and TIC-19 had also been submitted for security certificates to the Ministry of agriculture. Using insect-resistant materials with security certificates as the source of exogenous genes, the trangenic plants obtained subsequently could be carried out productive experiment skipping environmental release and semiplant test which was time saving and work less. Combining modern biological technology and traditional breeding method, transforming the insect-resistant genes into cultivated varieties by backcrossing transformation, provides a broad prospect for full use of acquired resistance transgenic materials.