Transgenic corn is a transgenic crop. Transgenic technology is the use of modern biotechnology, through artificial cloning to transfer the required target gene into the recipient organism, so as to improve the original traits of the recipient organism or give it new excellent traits. As an important achievement of biotechnology industrialization, transgenic corn has been widely used in the world.
Transgenic maize breeding involves many traits, such as insect resistance, herbicide resistance, high quality, stress resistance, disease resistance, high yield, bioreactor and so on. Among the developed products, insect resistance and herbicide resistance are the most widely used.
The safety problems of transgenic crops are mainly reflected in the following aspects: gene drift may occur, and foreign genes may be transferred from transgenic crops to non-transgenic crops through hybridization, which will affect the growth of non-transgenic crops and then affect the structure of biological communities. Because of the existence of reproductive isolation, it is difficult for them to cross with other plants, and the pollen propagation distance is limited and the survival time is limited.
Development history
Since 1995 insect-resistant and herbicide-resistant corn was commercialized in the United States, the popularization and application of transgenic corn has been very rapid. According to ISAAA's statistical data, from 1996 to 20 16, the global cumulative planting area of transgenic corn reached 600 million hm2.
Among the countries with large planting area of transgenic corn, the United States ranks first, reaching 35 million hm2 in 20 16 years, accounting for 92% of the total corn area; Brazil is 6,543.8+05.7 million hm2, Argentina is 4.7 million hm2 and Canada is 6,543.8+500,000 hm2. There are 23 1 registered maize transgenic events, which does not include most transformation events in China.
There are many genetic transformation methods applied to maize and their improved types, and each method has its own advantages and disadvantages. The earliest successful report of transgenic maize began with protoplast transformation of 1988, and the earliest genetic transformation method for cultivating fertile transgenic maize was gene gun transformation.
Transformation events such as MON8 10, GA2 1 and NK603 were obtained by optimizing the conditions with immature embryos and suspension cells as recipients. Agrobacterium-mediated genetic transformation of maize was reported relatively late, and it was not until Japan Tobacco Company announced the method and standard procedure of immature embryo transformation based on Agrobacterium-mediated that it was widely used in industry.