The research of crop biotechnology breeding is no longer in the laboratory stage, but has entered the practical application and commercialization stage. The planting area of transgenic plants in the world is growing rapidly, with the number of countries planting transgenic plants increasing from 1 in 1992 to 6 in 1996 and 9 in 1998, and further expanding to 12 in 199. The global planting area of transgenic plants 1996 was only10.7 million hectares, 1997 was10.7 million hectares, 1998 and 1998 were 27.8 million hectares and/kloc-0, respectively.
The commercialization of transgenic plants in the United States is progressing rapidly, and its popularization and application are in the forefront of other countries. 1994, the transgenic tomato developed by Calgene Company of the United States entered commercial production for the first time. By the end of 1998, more than 30 transgenic plants had been approved for commercial production. The United States accounts for 72% of the global planting area of transgenic plants, from 65438 to 0999, reaching 28.7 million hectares. Followed by Argentina 6.7 million hectares; 17%; 4 million hectares in Canada, accounting for10%; China ranks fourth, with planting area 1.999 reaching 300,000 hectares, accounting for 1%. The planting area in other countries is less than 1%.
The main types of transgenic plants are soybean (54%), corn (28%), cotton (9%) and rape (9%), and the proportion of potato, zucchini and papaya is less than 1%. According to the characters of transgenic plants, herbicide-resistant plants account for 765,438+0%, such as herbicide-resistant soybeans (54%), rape (9%), corn (4%) and cotton (4%); Insect-resistant transgenic plants account for 22%, mainly insect-resistant corn (19%) and insect-resistant cotton (3%). Insect resistance and herbicide resistance accounted for 7%, mainly corn (5%) and cotton (2%); The proportion of transgenic plants with antiviral properties is less than 1%.
The industrialization of transgenic plants, especially transgenic crops, has brought great economic and social benefits because it has increased the yield, reduced the use of herbicides, pesticides and other pesticides, saved a lot of labor. Global sales of transgenic plants doubled from $75 million in 1995 to $235 million in 1996. Supported by the National 863 Program, the Institute of Biotechnology of Chinese Academy of Agricultural Sciences successfully synthesized and transformed the Bt gene of plants, and obtained transgenic cotton varieties and strains with high resistance to cotton bollworm. In addition, the Cotton Institute of China Academy of Agricultural Sciences, Nanjing Agricultural University and Shanxi Academy of Agricultural Sciences also took transgenic insect-resistant cotton as their parents, and bred a batch of transgenic insect-resistant hybrid cotton combinations with insect-resistant ability above 80% and yield 15% higher than the main varieties. The breeding and large-scale popularization and application of insect-resistant cotton with independent intellectual property rights in China indicate that the research on transgenic plants in China has begun to enter the industrialization stage.
In order to effectively control the harm of rice pests, the Institute of Biotechnology of Chinese Academy of Agricultural Sciences and Huazhong Agricultural University have successfully obtained Bt transgenic hybrid rice, and the poisoning effect on Chilo suppressalis, Chilo suppressalis and rice leaf roller reached 95%. Zhejiang Agricultural University (now incorporated into Zhejiang University) has also successfully introduced Bt gene into early rice varieties. Bt transgenic rice has entered the stage of environmental release. Insect-resistant rice with CpTI gene successfully developed by Institute of Genetics, Chinese Academy of Sciences has also been approved for pilot test and environmental release in Beijing, Fujian and Shanxi respectively. In addition, the transgenic corn with corn borer resistance developed by China Agricultural University, the transgenic rice with brown lice resistance developed by the Institute of Genetics of Fudan University, and the transgenic poplar with insect resistance developed by the Institute of Microbiology of China Academy of Sciences and the Forestry Research Institute of China Academy of Forestry have also entered the stage of environmental release.
Disease-resistant genetic engineering
The Institute of Biotechnology, Chinese Academy of Agricultural Sciences successfully synthesized and transformed the antimicrobial peptide gene from silkworm moth, and introduced it into Milla, the main potato variety in China, to obtain a transgenic strain with improved I ∽ III disease resistance, which has been approved by the Ministry of Agriculture for environmental release in Sichuan Province. Antibacterial peptide genes have been supplied to more than 0/0 research units in China to carry out genetic engineering research on bacterial diseases such as rice bacterial blight, potato soft rot, peanut tomato bacterial wilt, Chinese cabbage soft rot, citrus canker, mulberry and eucalyptus bacterial wilt, cherry clubroot and so on.
Bacterial blight is also one of the most serious diseases that endanger rice production. Xa2 1 transgenic rice Minghui63, which has been successfully developed by Institute of Biotechnology of Chinese Academy of Agricultural Sciences in cooperation with foreign countries, has been planted in Anhui Province and Hainan Province respectively. Xa2 1 transgenic rice with bacterial blight resistance developed by Huazhong Agricultural University and Institute of Genetics of Chinese Academy of Sciences also entered the pilot stage respectively.
Mycosis is also a disease that seriously affects crop yield. The Institute of Biotechnology of Chinese Academy of Agricultural Sciences cooperated with Shanghai Institute of Plant Physiology of China Academy of Sciences to successfully clone and transform chitinase gene and glucose oxidase gene from plants. These two genes were introduced into cotton by pollen tube pathway, and transgenic cotton resistant to verticillium wilt, Fusarium wilt and Fusarium wilt was obtained. These strains performed well in the nursery and have now entered the pilot stage.
China's antiviral genetic engineering has also made good progress. Peking University cloned tobacco mosaic virus TMV, cucumber mosaic virus CMV, potato X virus and other China strains, rice dwarf virus coat protein genes. The successfully cultivated sweet pepper and tomato with resistance to cucumber mosaic virus have been tested in Yunnan and Fujian respectively or released into the environment. Transgenic peanut resistant to stripe virus cultivated by Oil Research Institute of China Academy of Agricultural Sciences, cabbage resistant to turnip mosaic virus cultivated by Vegetable Research Center of Beijing Academy of Agricultural Sciences, and transgenic melon resistant to cucumber mosaic virus obtained by nuclear technology biotechnology of Xinjiang Academy of Agricultural Sciences have all entered the pilot test respectively. In addition, some research institutes in China have also obtained papaya resistant to ring spot virus (PRSV), wheat resistant to yellow dwarf disease and genetically engineered plants resistant to yellow mosaic virus.
Genetic engineering of plant stress resistance
Some progress has been made in salt-tolerant genetic engineering in China, including the cloning of proline synthase (proA), spinach alkali dehydrogenase (BADH), mannitol phosphate dehydrogenase (mtl) and sorbitol phosphate dehydrogenase (gutD). Through genetic transformation, alfalfa with 1%NACL tolerance, strawberry with 0.8%NACL tolerance and tobacco with 2%NACL tolerance were obtained. These transgenic plants. The Institute of Genetics of Chinese Academy of Sciences introduced BADH gene into rice, and the transgenic rice obtained has high salt tolerance and can bear fruit in Yantian.
Genetic engineering of plant quality improvement
Peking University transformed the gene encoding essential amino acids into potato, and obtained a potato strain with high essential amino acids content. These strains have been planted in Inner Mongolia and are ready to enter the pilot development. China Agricultural University successfully introduced high lysine gene into maize, and the lysine content of transgenic maize was higher than that of control 10%.
In genetic engineering to control plant development, ripening technology has delayed the research of mature tomatoes. Huazhong Agricultural University and Institute of Botany, Chinese Academy of Sciences obtained the transgenic fans respectively, and the storage time can be extended by 1∽2 months, and some of them can reach more than 80 days. 1997 The Genetic Engineering Safety Committee of the Ministry of Agriculture has approved this storage-resistant tomato for commercial production. The new storage-resistant tomato varieties cultivated by China Agricultural University using antisense gene technology have been released into the environment.
Peking University successfully introduced chalcone synthase gene related to anthocyanin metabolism into Petunia. The color of transgenic Petunia shows the change that is not found in nature, which improves the ornamental value of flowers. Research on transgenic orchids and gerbera jamesonii is under way.
Plant chloroplast genetic engineering
The Institute of Biotechnology, Chinese Academy of Agricultural Sciences is an earlier unit in China to carry out research on plant chloroplast genetic transformation. 1996 established the genetic transformation system of tobacco chloroplast, successfully introduced Bt gene into tobacco chloroplast, and the transgenic plants had remarkable insecticidal effect. They also introduced nitrogenase genes (nifH and nifM), drug resistance gene (bar gene) and green fluorescent protein (GFP) into tobacco chloroplasts.
Plant bioreactor
The research on using transgenic plants as bioreactors to produce medicinal proteins has attracted more and more attention in various countries, and the production of oral vaccines using transgenic plants is one of the hot spots of research and exploration. Researchers from Institute of Biotechnology, China Academy of Agricultural Sciences introduced hepatitis B virus surface antigen gene into potatoes and tomatoes, fed them to mice, and detected highly protective antibodies, the concentration of which was enough to protect human beings. The Institute has also explored the use of plant chloroplasts as bioreactors to produce medicinal protein, and introduced hepatitis C virus antigen gene into Chlamydomonas chloroplasts. Using transgenic plants to produce oral vaccines can greatly reduce the production cost of vaccines, which has a good development prospect in developing countries. In 20001year, the global commercial planting area of transgenic plants reached 52.6 million hectares, of which the planting area in China was10.5 million hectares, three times that in 2000, making it the fastest growing country in the world. On the one hand, the main reason is that the developed products have good effects, which have attracted the attention of farmers and increased the planting area; On the other hand, due to the country's increased research efforts, new technologies and new products of transgenic plants are constantly produced.
Insect-resistant transgenic plants
200 1, transgenic insect-resistant cotton has made new breakthroughs on the basis of great achievements. The patent of insect-resistant cotton gene "fusion gene encoding insecticidal protein, expression vector and its application" by Institute of Biotechnology, Chinese Academy of Agricultural Sciences won the China Patent Gold Award issued by China National Intellectual Property Administration and World Intellectual Property Organization. At the same time, bivalent transgenic insect-resistant cotton SGK32 1 has also passed the examination and approval of Hebei Variety Approval Committee, which indicates that China is in a leading position in the research field of transgenic insect-resistant cotton. SGK32 1 has passed the safety evaluation of agricultural genetically modified organisms, and has been approved for commercial production in Shanxi, Hebei, Shandong, Henan, Anhui and other places, and released in Hubei. According to the results of regional trials in 2000 and 20001year, the early maturity of SGK32 1 is obviously better than other varieties, and the lint yield per mu before frost is 75.4 kg, which is equivalent to 93.4% of the control insect-resistant hybrid. The fiber quality of this variety is good, the length is 29.2 mm, the specific strength is 29.4 cm/tex, the micronaire value is 4.8, and the insect resistance is outstanding.
Up to now, there are 4 insect-resistant cotton varieties1in China, including univalent cotton 1 1. They are: GK 1 (Guo Kang 1), GK 12 (Guo Kang 12), GK 19 (Guo Kang 19), GK22 (Guo Kang 22). GKz 10 (Lu Mianyan 15), GKz 13 (Lu RH- 1), GKz6 (No.38 of China Cotton Institute) and GKz8 (No.3 of Nankang); There are three bivalent cotton, namely: sGK32 1, sGK9708 (China Cotton Institute 4 1) and sGK5 (Xinyan 96-48). These insect-resistant cotton varieties have strong resistance to cotton bollworm, good quality traits and high yield. At the same time, a number of insect-resistant cotton varieties with strong competitiveness were cultivated, including two hybrid cotton varieties (Lu H95 13 and Zhongkangza No.5) and two conventional cotton varieties (ZGK9708 and Lu S6 145). In addition, six potential varieties and four hybrid cotton are participating in national regional trials. 200 1 domestic insect-resistant cotton has been popularized in Hebei, Henan, Shanxi, Shandong, Hunan, Hubei, Jiangsu, Anhui, Xinjiang, Liaoning and other provinces and cities, accounting for 43.3% of the domestic market share of insect-resistant cotton. Together with Monsanto's insect-resistant cotton, in 200 1 year, the planting area of transgenic insect-resistant cotton reached 3 1% of the national cotton planting area, with more than 3.5 million farmers.
In terms of insect-resistant transgenic rice, transgenic rice with SCK gene (modified cowpea protease inhibitor gene) developed by Institute of Genetics and Developmental Biology, Chinese Academy of Sciences has been tested in Fujian for 5 years. It was identified that its field control effect on Chilo suppressalis was 90- 100%, its resistance to rice leaf roller was 8 1- 100%, its control effect on Chilo suppressalis was 62.6-63.9%, and its control effect on Chilo suppressalis was 83.9%. Due to policy reasons, it is impossible to popularize planting in a large area for the time being, but field experiments have been carried out in many areas and points. The food safety inspection of genetically modified rice has been basically completed, and the results show that there is no obvious difference between genetically modified rice and conventional rice. New transgenic rice varieties with non-selective markers, high expression and multivalent insect-resistant genes are being further developed.
A new silent insecticidal gene cry 1Ie 1 was cloned from Bt strain by China Agricultural University. The toxic protein expressed by this gene shows high insecticidal activity against Asian corn borer, and its status as a model gene in taxonomy has been confirmed internationally. This gene and its combination with cry 1A gene have applied for national invention patent. On this basis, the codon transformation of cry 1Ie 1 and cry 1Ac genes and the construction of prokaryotic and eukaryotic expression vectors were further completed, and the insecticidal activity identification of the transformed genes is under way.
Disease-resistant transgenic plants
The Institute of Genetics and Developmental Biology of Chinese Academy of Sciences and foreign units successfully located the cloned disease-resistant gene Xa2 1, and transformed it into high-yield and high-quality rice varieties Minghui 63, Zhenshan 97B, Yan Hui 559, Taihu Jing6, Peiai 64S, C4 18, 8706 and Zhonghua through the original Agrobacterium-mediated transformation system of the gene. Resistance analysis showed that these transgenic lines were highly resistant to 19 different strains of Xanthomonas oryzae pv.oryzae. Rice, including 9 Philippine races, 3 Japanese races and 7 pathogenic species in China, has an epidemic area less than 10%. The resistance of most Xa2 1 transgenic lines is stronger than that of Xa2 1 gene donor IRBB2 1, indicating that Xa2 1 still retains high resistance and broad-spectrum resistance to bacterial blight under different genetic backgrounds. Objective some transgenic strain have entered that pilot stage.
China Agricultural University introduced the coat protein gene of wheat yellow mosaic virus (WYMV), 72kDa protein gene related to bacterial transmission, RNaseIII, 2-5A system and other target genes into wheat by using the established high-frequency genetic transformation system of wheat, and obtained a variety of virus-resistant transgenic lines. Among them, 50 kinds of materials, such as NY-8, have passed the national biosafety examination and approval and entered the field test. A number of strains with excellent comprehensive agronomic characters and remarkable antiviral ability were screened, and the antiviral mechanism mediated by transgenic silence was confirmed in cereal crops for the first time.
China Rice Research Institute and other units introduced insect antimicrobial peptide gene into rice immature embryos through transgenic technology, using gene gun technology or pCBl vector, and obtained transgenic rice plants resistant to bacterial diseases. Experiments have proved the resistance of transgenic rice to bacterial blight. Rice and Xanthomonas. Rice was enhanced in greenhouse and showed its genetic stability.
The Institute of Biotechnology of China Academy of Agricultural Sciences cooperated with Shanghai Institute of Plant Physiology of Chinese Academy of Sciences, successfully cloned and transformed chitinase gene and glucose oxidase gene from plants, and obtained transgenic cotton resistant to verticillium wilt and Fusarium wilt, which has now entered the pilot stage.
Transgenic plant reactor
The application of tobacco mosaic virus (TMV) as an expression vector in plant bioreactor was studied by Shanghai Institute of Plant Physiology, China Academy of Sciences. Using this method to express the surface antigen polypeptide of foot-and-mouth disease virus on a large scale, and prepare efficient, safe and cheap recombinant foot-and-mouth disease vaccine. In this study, a great breakthrough was made in the expression of exogenous peptides by using the genomic cDNA mutant library built by local strains of TMV. The recombinant TMV was obtained, which can fuse and express a variety of foot-and-mouth disease virus surface antigen peptides, up to 3 1 peptide. The recombinant virus has stable systemic infection ability, and more than 65438±0mg of high-purity fusion protein can be obtained per gram of fresh tobacco leaves. A simple and effective process route was found for large-scale purification of tobacco virus protein and preparation technology of recombination vaccines.
Quality improvement of transgenic plants
Zhejiang Academy of Agricultural Sciences put forward the technical route of using antisense PEP gene to improve the oil content of rape seeds for the first time in the world from the perspective of photosynthetic product distribution. Based on this, antisense PEP gene was constructed and introduced into rape genome through Agrobacterium-mediated pathway, and several batches of antisense PEP gene rape plants were obtained successively. The oil contents of Chaoyou 1 and Chaoyou 2 reached 47.4% and 52.82% respectively, both of which were more than 25% higher than the traditional varieties, and they were the highest oil contents in the world. It broke the situation that the oil content of rape in the Yangtze River valley in China hovered at 37%~43% for a long time, and achieved a breakthrough in the oil content of rape seeds in China.
Yangzhou University and Institute of Genetics and Developmental Biology, Chinese Academy of Sciences have isolated and cloned rice seed starch synthesis related genes: starch branching enzyme Sbe 1, starch branching enzyme Sbe3 and soluble starch synthase SSS, as well as rice endosperm-specific expression gene promoter elements Gt 1, GluB- 1, RP5 and RAG 1. An engineering vector containing sense or antisense starch synthase and high lysine content protein (LRP) gene was constructed, and more than 800 transgenic rice plants with different quality genes were obtained through transformation. Molecular identification of some transgenic rice has been completed.