Environmental Safety Evaluation And Quality Analysis Of Insect-resistant And Herbicide Transgenic Maize Jikang 309

Maize is the main food crop in China,but the harm of pests and weeds poses a great threat to the yield and quality of corn,which causes corn to reduce its production and cause huge economic losses.With the rapid development of transgenic technology,transgenic insect-tolerant herbicide-combined corn has successfully solved the dual hazards of insect pests and weeds.However,with the development of cry genes,pests have also shown some resistance to gradual resistance to insect proteins.Therefore,searching for new genes can expand the insect resistance spectrum of insect-resistant genes,and transforming the original insect-resistant genes can lead to new insect-resistant genes.In this research group,the cry1 Ab was modified by codon optimization and genetic modification,and a new insect-resistant gene cryNGc was obtained.The transgenic maize Ji Kang 309,which was transferred to cryNGc and bar genes,has entered the environmental release phase of the application.We need to analyze and evaluate the genetic stability and environmental safety of Ji Kang 309 transgenic corn.The cryNGc and bar were detected by PCR in the transgenic maize Ji Kang 309 plant.The results showed that both genes were present in the transgenic corn.In order to further verify whether the two genes can be normally transcribed,RT-PCR method was used for analysis.The results showed that both genes can be normally transcribed;Southern blot results proved that the target gene existed as a single copy in transgenic corn,with A certain degree of genetic stability;using the method of genome sequencing to find the flanking sequences of the transgenic maize and designing specific primers to establish a specific detection method of the transgenic corn.The transgenic maize anti-insect protein and the prokaryotic expressed insect-resistant protein were analyzed by test strip detection,protein expression and purification,SDS-PAGE,Western blot and mass spectrometry detection methods.The results showed that prokaryotic expression yielded a protein with a size of approximately 65 kD and the protein was purified.Western blot was used to detect purified protein,transgenic corn protein and prokaryotic expression protein.The plant protein and prokaryotic expression protein had consistency in immunogenicity.Through mass spectrometry analysis,the two proteins were also consistent in amino acid composition.Field-resistance herbicide and insect resistance test,non-target herbicide test,survival competitiveness test in cultivated land,yield test in the wasteland competition test and germination rate test results of the transgenic corn showed that Ji Kang 309 has high resistance to Asian corn borer Insect resistance,able to tolerate 6 times herbicide and no competition for survival between the corresponding non-transgenic corn and native varieties;genetically modified corn has no competitive advantage in moisture and nutrient content relative to weeds.Therefore,it is judged that genetically modified corn will not evolve into weeds,germination rates,and non-transgenic corn were not significantly different.The total nutrient content,fatty acid composition,amino acid composition and mineral element content of transgenic corn and non-transgenic corn were analyzed.The results showed that there was no significant difference in the content of nutrient components between transgenic corn and non-transgenic corn.The above studies showed that genetically modified corn has genetic stability,and there is no competition with non-transgenic corn in the field,and weeds have no competitive advantage.The yield and germination rate are not significantly different from non-transgenic corn.Therefore,it is safe for the environment.The results of nutrient composition analysis showed that there was no difference in the types and contents of nutrients between transgenic corn and non-transgenic corn.These results also provide a guarantee for the environmental safety evaluation of genetically modified corn,and also provide a theoretical basis for the food safety evaluation of genetically modified corn.