Although CAAS has always had an agricultural focus, the range of disciplines it encompasses is astonishingly broad. The academy is committed to generating the best basic and applied research possible, something it achieves through the acquisition of top talent and the provision of exceptional infrastructural and knowledge support to its researchers.
Here, some of the most outstanding achievements that have come out of CAAS in the 56 years since its founding, are presented.
1. Biological Resources
Since its inception, CAAS has been vigorously engaged in the collection, preservation, identification, and evaluation of indigenous and exotic landraces, breeds, lines, genetic materials, and wild species, which have enriched China’s resources of plant and animal germplasm and laid a solid genetic basis for the breeding of new varieties.
Crop Germplasm Resources Preservation: CAAS possesses one national long-term gene bank and 10 medium-term gene banks as well as 12 national crop germplasm nurseries. Preserved genetic resources include the most important grain and cash crops, such as rice, wheat, maize, coarse cereals, legumes, cotton, oil crops, bast fiber crops, tea, forage, vegetables, and staple fruits. An integrated system for the conservation of national crop germplasm resources was established by CAAS in 2003, and currently has over 420,000 accessions. CAAS has also established the Chinese Crop Germplasm Resources Information System (www.cgris.net) to acquire, analyze, and manage germplasm information.
Looking to the future, a new long-term gene bank is being built to meet the needs of Chinese agricultural development over the next 50 years, with a storage capacity of 1,500,000 accessions.
Domestic Animal Genetic Resources Conservation: A conservation system for domestic animal genetic resources has been established at CAAS that includes livestock, poultry, and economically important animal breeds, representing 15 animal species. Detailed, standardized information on all domestic animals has been well documented, which is helpful in research and utilization of these resources.
Free and open online access to the Chinese Domestic Animal Genetic Resource Information System (www.cdad-is.org.cn) and the Chinese Special Animal Genetic Resource Information System has been provided by CAAS. From 2002 to present, these websites have been visited over three million times.
Agricultural Microorganisms Collection and Conservation: Established in 1979, the Agricultural Culture Collection of China (ACCC) preserves more than 18,000 strains of microorganisms, predominantly pathogenic and beneficial bacteria, actinomeycetes, yeast, and filamentous fungi. ACCC distributes about 3,000 strains annually and has become an agricultural microorganism resource center in China.
CAAS has made breakthroughs in the preservation of crop germplasm resources and their innovative utilization. They include the following:
Collection, Conservation, Evaluation, and Utilization of Chinese Crop Germplasm Resources: A germplasm preservation system integrating a redundant long-term gene bank plus multiple medium-term gene banks has been established, holding more than 420,000 crop germplasm accessions. Additionally, a comprehensive reproduction and regeneration system to ensure the genetic integrity of preserved germplasm resources was developed to facilitate germplasm evaluation, genetic diversity assessment, gene discovery, and germplasm enhancement.
Diversity and Descriptor lists for Crop Germplasm Resources and their Application: The careful study of the genetic diversity of 110 crops has resulted in the generation of 512 maps showing the geographical density distributions of these resources, together with descriptor lists (lists of specific plant attributes) and data standards for these crop germplasm resources. More than 110 volumes of descriptor lists were compiled and disseminated, greatly improving the efficiency and benefits of the crop germplasm database.
Derivation and Use of ID-Type Cytoplasmic Male Sterility Rice: The derivation of a new cytoplasmic male sterility (CMS) variant from Indonesian native rice germplasms allowed for the creation of three ID-type CMS lines with a high out-crossing rate. More than 200 ID-type hybrid rice combinations have been released and planted over an area of more than 30 million hectares.
Genetic Analysis of Important Rice Germplasms: Genetic material was isolated and analyzed from a series of rice strains with differing morphological, physiological, chemical, and biological characteristics. Almost 50,000 genetic differences were mapped and entered into a biomarker database. This analysis established the world’s first collection of morphological markers for isogenic lines from the indica strain, information that is now widely used. Additionally, in-depth genetic information from insect- and disease-resistant genes from wild rice, landraces, and specially bred species was collected and stored in a searchable database. This resource allows for the identification of key functional genes and ultimately the creation of new and innovative rice varieties.
Conservation and Utilization of Wild Cotton Germplasm: More than 6,000 economically and agriculturally important cotton germplasm as well as threatened varieties have been collected and stored at the Wild Cotton Nursery in Sanya, Hainan Province. Over 700 elite cotton parent materials were created from those germplasms, while over 7,000 accessions (some reused frequently) have been provided to cotton breeders around the world. Moreover, 172 novel cultivars have been developed in China that come directly or indirectly from these parent materials. The overall area planted with new varieties is currently more than 37 million hectares.
2. New Plant and Animal Varieties
Development of new animal and plant varieties is an important part of the central research focus of CAAS. The major plants studied include rice, wheat, corn, cotton, oil crops, vegetables, fruit trees, bast fiber crops, and tea, amongst others. Pigs, cattle, sheep, chicken, ducks, other large livestock, and economically important animals are also studied. The new plant and animal varieties developed by scientists at the academy are used widely in agricultural production, and a number of varieties of grain, cotton, and oil crops have become the predominant crops planted in certain agricultural areas in China. These crops have made important contributions to ensuring national food security, promoting the development of modern agriculture, and increasing the financial stability of farmers. In 2011 and 2012 alone, 181 new varieties were released, some of which are detailed here.
Application of Dwarf Male-Sterile Wheat in Breeding: Breeding methods based on dwarf male-sterile wheat, now widely used in China, have significantly improved wheat breeding efficiency. Utilizing these methods, 42 new varieties have been developed including “Lunxuan 987,” which produced a record yield of 10.73 tons per hectare. From 2001 to 2010, new varieties have covered accumulatively 12.3 million hectares and have boosted grain output by 5.6 million tons in total. A number of elite lines developed using the dwarf male-sterile wheat method are in regional trials and the results so far have been very positive.
Breeding System for Super Hybrid Rice: To improve the vigor of rice crops, cutting-edge molecular analysis and screening techniques have been developed to combine the best physical characteristics (root strength, photosynthesis capacity, disease resistance) of japonica and indica rice through introgression crossing. Application of this methodology resulted in the creation of a series of high-vigor super hybrid rice varieties, including "Guodao 1” and "Guodao 6," which have been widely cultivated in Yangtze River Region in China.
Phytase Genetically Modified Maize: Genetically modified (GM) phytase maize, when used as animal feed, will abolish the need for industrially produced phytase as an additive (phytase is needed to aid availability of phosphorus for absorption by animals), thereby reducing feedstuff costs dramatically. It will also reduce the need to supplement feed with phosphorus by 80–120 tons annually, saving precious phosphorus resources. This GM phytase maize was issued with a GM organism production application safety certificate in 2009 by the Ministry of Agriculture.
Transgenic Cotton: Utilizing elite germplasm and new breeding technologies, a number of novel transgenic cotton varieties have been developed. These include CCRI 24, with a short growth period and high fiber quality; CCRI 29 with improved yield, high quality, resistance to multiple diseases and improved adaptability; and CCRI 41, carrying two insect-resistance genes and showing superior growth efficiency and a broad growing area. New transgenic lines created in 2012 that show improved fiber quality and boll size will provide parental stock for a second generation of transgenic cotton in China.
Soybean: A novel high-yield, high-protein and adaptable soybean variety, “Zhonghuang 13,” was developed in China using a special breeding system. This superior variety has the largest geographical growth range in the country, now standing at over 4.8 million hectares. It was intentionally developed to be planted across 14 provinces and has held the record for the largest soybean growth area since 2007.
Rapeseed: Dozens of high-yield (up to 64.8% oil), double-low (low erucic acid, low sulfuric glucoside) varieties of rapeseed have been developed over the past few decades, including a series of open-pollinated “Zhongshuang” varieties and a raft of hybrid “Zhongyouza” varieties. The planting area for these particular crops currently covers one-third of the total national acreage of rapeseed.
Peach and Nectarine: A breeding system for high-quality, adaptable peaches and nectarines has been established and utilized to create 25 new nectarine, peach, and ornamental varieties by taking advantage of high-quality germplasms. Among them, five new nectarine varieties, including “Zhong Youtao 4,” hold the top five spots for acreage of trees in nectarine cultivation areas. The planting of some of these new cultivars around the country has reinvigorated peach cultivation in China.
Capsicum: Extensive work has been carried out to develop sweet peppers and chili peppers that have resistance to viruses and other diseases, particularly phytophthora blight. In addition, the genetic loci controlling cytoplasmic male sterility in pepper were identified and analyzed. This information was used to create 11 elite inbred lines, from which five hybrid offspring have been successfully generated and released. These new varieties are now major cultivars, covering large growing areas in pepper-producing regions of China.
Datong Yak: CAAS scientists have created the Datong Yak, the first improved yak breed in the world, developed by crossing large wild yak males with smaller, domestic yak females. The new breed is genetically stable, has relatively strong disease resistance, and shows good environmental adaptability. Meat production from the Datong yak is 20% higher, hair and fur production 19% higher, and the reproductive rate is improved by 15% to 20%. About 300,000 vials of frozen Datong yak semen were distributed throughout the yak rearing areas in China and have improved the productivity of domestic yaks dramatically.
Peking Ducks: Numerous advances in breeding techniques and molecular marker-assisted selection have improved the productivity of Peking duck significantly over the past three decades. Two specialized strains of Peking duck have been successfully bred, the rapidly growing Z-type duck with high lean meat and good feed efficiency, and Nankou-I ducks with high skin fat. Every year, over 100 million commercial birds are produced from these two strains, with annual economic benefits of above 3 billion Yuan (US$485 million).
3. Applied Agricultural Technologies
In the area of applying new agricultural technologies in China, CAAS has a solid focus on innovation. This includes not just new ideas, but the integration and full application of those ideas to make a real difference in guaranteeing national food security and ecological security.
Through intensive research and development, breakthroughs have been made in a number of key areas, for instance in the improvement of agricultural products, more efficient use of resources, and the application of agricultural biotechnology for the prevention and control of major animal and plant diseases, as well as the prevention and control of agricultural pollution, and enhancement of soil fertility.
Some specific achievements in these areas are outlined below.
Quality Testing Protocols for Chinese Wheat Products: Noodles and steamed bread are important staples in the Chinese diet. CAAS has established standardized testing and evaluation methodologies for these and other traditional Chinese products. Key factors responsible for noodle quality have been identified and comparative genomics has been employed to characterize how genetic variations impact food quality. Over 40 gene-specific markers have been validated and used to characterize germplasms in China and at the International Maize and Wheat Improvement Center (CIMMYT) in Mexico. Three improved varieties developed by CAAS and with excellent pan bread or noodle quality have become leading varieties in northern China.
Integrated Management of Wheat Stripe Rust: The virulent fungus Puccinia striiformis Westend causes stripe rust on wheat in many areas around China. At CAAS, technology has been developed that can forecast regional epidemics of stripe rust early and with the accuracy of close to 100% based on an analysis of the variation in the inoculum from the source of the outbreak. Studies have elucidated the genetic basis for the evolution of virulence in pathogens as well as the reasons for the failure of plant resistance in wheat cultivars. A strategy of ‘headstream’ management to identify the sources of pathogen and quickly control their spread has been widely implemented across the country, resulted in a significant reduction in crop losses, accumulatively saving 9.3 billion Yuan (US$1.5 billion) from 2009 to 2011.
High Yield and High Efficiency Maize Production: Researchers investigated the key factors and technological requirements for the most efficient production of maize. Thirteen different systematic approaches were developed, each suited to a different ecological regions or niches in China, such as the southwest, the north, or the Huang-huai-hai Plain. These models have proven highly successful at boosting maize production, consistently generating record high yields in many different ecological regions.
In Vitro Culturing of Cotton: A new methodology has been developed that uses explants of petioles (the stalk attaching leaf to stem) or hypocotyls (part of the plant seedling) to more easily create cotton seedlings in vitro. Utilizing an Agrobaterium tumeficiens-mediated transformation protocol, the transformation ratios can be increased 1.9- to 3.5-fold over wild type. Transformation cycles are therefore greatly shortened and the efficiency of tests for validation of gene function significantly increased.
Innovations in Urban Horticulture: The cultivation of food in an urban setting has grown in importance as more people move to large cities, which has given new impetus to CAAS’s urban horticulture program. One example is a novel cultivation technique for sweet potato in which the above-ground tuberous root can be continuously harvested, while leaving the below-ground root system untouched so as to allow for absorption of nutrients.
In addition, a number of three-dimensional soilless cultivation systems have also been developed, including wall, column, and mobile pipeline cultivation. These techniques have greatly improved the efficient utilization of both space and light, and facilitated the promotion of urban agriculture.
Monitoring System Driven by Remote Sensing: Crops in China are grown in complex and diverse landscapes and commonly mixed with other vegetation. To effectively and efficiently monitor crop conditions at a regional level, an integrated crop monitoring system has been built, combining remote sensors, in situ observation stations, and wireless sensor networks. Using data generated by this system, discriminative crop diagnostic techniques incorporating complex quantitative inversion algorithms were developed and deployed nationwide to gather data on major crop and agro-environmental variables for assessment and analysis. The system has now been running for a decade, providing rapid and reliable information to support important decisions regarding the management of crops throughout China.
4. Agricultural Products
As China transforms itself into a modern agricultural nation—balancing the needs of the industrial sector with a drive to innovate—there is a growing urgency for new and better agricultural technologies and products. These cover a broad swath of areas, from vaccines and detection reagents for infectious diseases, to better agricultural machinery and improved fertilizers. CAAS has successfully developed many such items, producing them on a large scale for standardized application across the country. Additionally, work done at CAAS has significantly increased the productivity of arable land, improved the utilization of limited natural resources, boosted labor productivity, and increased farmers’ income. From 2001 to 2010, CAAS was awarded 36 national awards for developing new veterinary drugs, pesticides, and fertilizers; in 2011 and 2012, another 14 such awards were added.
Just a few of the representative successes are described below.
H5N1 Avian Influenza: China is a leader in avian influenza vaccine development and distribution. CAAS established a platform for H5N1 vaccine development using plasmid-based reverse genetics (RG). H5N1 RG vaccines have been widely used in China, Vietnam, Indonesia, and Egypt, and have played an important role in the control of H5N1 avian influenza in domestic poultry. CAAS has also developed a live attenuated Newcastle disease virus (NDV) vectored H5N1 influenza vaccine, which provides protection against both Newcastle disease and H5N1 in chickens. This is the first widely used RNA virus vectored vaccine in the world.
Foot-and-Mouth Disease: Researchers at CAAS have been instrumental in the surveillance, diagnosis, prevention, and control of foot-and-mouth disease (FMD) in China. Their work on virus origins and pathways of transmission have enabled the creation of effective diagnostic techniques and the generation of vaccines against type O, A, and Asia I FMD strains, thereby reducing the occurrence of outbreaks and limiting the spread of FMD.
Quinocetone: Quinocetone, an animal growth promoter, is the first such novel drug certificated in China. The compound took more than 20 years to develop, but now demonstrates high yield, good stability, and significant growth promotion, with apparently no toxicity, no side effects, and no environmental pollution. Quinocetone has been widely used in China to promote growth in pigs, broiler chickens, ducks, and fish.
Fertility of Upland Red Soil Areas in Southern China: Since 1982, long-term fertility experiments have been carried out in the red soil areas of southern China. Comprehensive fertility improvement methodologies have been established that have enhanced productivity through the use of eight compound fertilizers (specifically for upland crops), four multi-function conditioning compound fertilizers, and four upland red soil conditioners. These fertilizers and soil conditioners are now manufactured by 10 fertilizer companies in Hunan, Jiangxi, Guangxi, and Guangdong provinces, with an annual production of more than 320,000 tons. The methodologies have been successfully applied over approximately 3.5 million hectares in southern China.
Healthy and Nutrition in Piglets: Research into various aspects of piglet health has been undertaken at CAAS, including piglet rearing and feeding patterns, physiological stress induced by weaning, the nutritional and anti-nutritional effects of components in feedstuff, nutritional requirements, and the importance of the gut microbial balance for intestinal health. Through this research, over 240 feed additives, premixes, and concentrated and specially formulated feeds that can enhance piglet health have been developed.
Multitarget Insecticides: As a means to manage insect pests that have developed resistance to multiple different insecticides, a series of effective, new multitarget pesticides have been developed. These include 20% abarmectin-monosultap microemulsion, 3% beta cypermethrin-emamectin microemulsion, 20% fenvalarate-malathion emulsifiable concentrates, and 15% abamectin-chlorpyrifos emulsifiable concentrates. These insecticides demonstrate high co-toxicity efficacy in laboratory assays and are effective at controlling pests such as Helicoverpa armigera, Cnaphalocrocis medinalis, Liriomyza sativae, and Nilaparvata lugens in the field. The use of multitarget insecticides significantly delayed the development of pesticide resistance under laboratory conditions when compared with insecticides containing a single active ingredient. Over two million tons of these insecticides have been deployed in the field to control crop resistant pests.
5. Advancing Basic Agricultural Research
CAAS attaches great importance to continuously pushing the boundaries of basic agricultural research and developing new paradigms through both theoretical analysis and practical experimentation. In this vein, CAAS has made a number of theoretical and methodological breakthroughs in the study of the genomics of important crops, the process of molecular breeding, the molecular basis of certain important agronomic traits, agricultural pest control, and the ecological and environmental security of genetically modified crops. From an academic perspective, CAAS scientists have excelled, increasing the number of published papers from 11,000 in the years 2001 to 2005, to over 20,000 from 2006 to 2010. Importantly, the number of papers indexed by the Thomson Reuters Science Citation Index and the Engineering Index rose fivefold from 514 to over 2,500 in the same period. The years 2011 and 2012 saw further dramatic improvement, with 10,000 publications, of which 2,620 were indexed, indicating increasing momentum for quality basic research and theoretical innovation at CAAS. CAAS scientists continue to publish influential papers in a range of fields in prestigious journals such as Science, Nature, Nature Genetics, PNAS, and The Plant Cell.
Some recent achievements from CAAS include:
Study of Important Functional Genes in Rice: In cooperation with researchers at the Chinese Academy of Sciences, OsSPL14/IPA1, a key gene in rice that promotes higher grain yield, was cloned, characterized, and then introduced into conventional rice varieties, increasing grain yields in recipient strains by ~10%. Candidate quantitative trait loci associated with 14 agronomically important phenotypic traits of Chinese rice varieties were identified through genome wide association studies; these are currently being studied further. Additionally, the role of epigenetic modifications in the determination of plant height and flower development was first reported, and a key gene related to rice fertility, pss1, was discovered.
Nitrogen Fixation in Rice: The complete genome sequence of the nitrogen-fixing bacterium Pseudomonas stutzeri A1501 was determined, leading to the identification of a 49-kb genomic island carrying the nitrogen fixation (nif) gene cluster. New genes required for the nitrogen fixation process have since been identified within this cluster. Knowledge of the genome sequence allows for further study of nif gene evolution and identification of rhizosphere traits needed for robust interaction between bacterium and host plant root. Moreover, it opens up new opportunities for the broader application of root-associated, nitrogen-fixing microorganisms in sustainable agriculture.
Sequencing of Important Crops Genomes: Using state-of-the-art next generation sequencing technology, CAAS scientists determined the complete sequence of cucumber, potato, Chinese cabbage, and cotton genomes, all of which are economically important crops. Careful analysis and annotation of these data yielded a goldmine of genetic information that can be practically applied in the breeding and management of these crops.
Assessment and Management of Transgenic Bt Cotton: CAAS scientists have been conducting long-term studies into how the cotton bollworm develops resistance to transgenic Bt cotton. Elucidation of resistance pathways has engendered new management strategies based on a multi-crop system (utilizing non-Bt host crops as a natural refuge), as well as techniques to control and delay the acquisition of resistance. Studies of the ecological impact of Bt cotton on target and non-target organisms (including insect pests and their natural enemies) has provided the necessary knowledge for the establishment of new systems for insect pest management in areas where transgenic Bt cotton is grown.
Evolution of H5N1 Viruses: Important research carried out at CAAS revealed the pathways by which H5N1 influenza viruses gradually acquired the ability to infect and kill mammalian hosts. This work uncovered some of the critical molecular components responsible for interspecies infection and transmission of H5N1 viruses in mammals, and revealed that the NS1 gene is a key determinant for the virulence of H5N1 viruses. Analysis of the NS1 gene sequence revealed functional information regarding virulence pathways.