The 13th International Symposium on Rice Functional Genomics was held at Huazhong Agricultural University (HZAU) on 22, September. In an interview, Zhang Qifa, academician of the Chinese Academy of Sciences and professor of HZAU, once again, brought up the principle of Green Super Rice: less pesticides and chemical fertilizer, water efficiency, drought resistance and high quality and yield.
Thanks to more than 20 years of accumulated experience of domestic rice scientists in research of gene functions, Green Super Rice enjoys great advantage in its application and promotion. “The rice is resource-saving and environmental friendly.” Zhang Qifa concluded.
According to the introduction of Yu Sibin, chief scientist of Green Super Rice Project and professor of HZAU, in recent years, new varieties featuring Green Super Rice have been planted for nearly 2.67 million hectares in Hubei, Anhui, Sichuan and Guangxi, reaping good economic and social benefits.
Demystifying Rice Genes
Rice is critical not only because it’s the staple food feeding one third of the global population, but it also has become a model plant in plant biology research. The mystery of other gramineous crops will be unraveled once agricultural scientists work out that of rice.
However, the gene combination of rice is quiet complicated. Functional gene identification entails defining genes and compiling dictionaries. Decoding rice genes is challenging for rice scientists.
“Each decoded gene means a progress in the exploration of rice gene and adds new knowledge and genetic resources to genetic modification”, Zhang Qifa said.
Statistics indicates that China, with 6875 papers, tops the SCI rice-themed papers over the last 10 years. According to Nature Index containing 68 high-quality scientific journals released by Nature Publishing Group, 117 rice-themed papers from China have been published in those high-quality journals, ranking the first worldwide.
As a key research institution on rice, the rice team of HZAU has successfully isolated and cloned over 100 important functional genes which control the character of production, quality, drought-resistance, disease-resistance and heterosis, among the first group cloning crop genes. All the achievements were published on the top journals including Nature.
The Third Breeding Breakthrough
Over the past half century, China’s rice breeding has made two major breakthroughs constituting the crucial part of the first Green Revolution.
The first breakthrough was the success in breeding for dwarfness in 1960s, raising the rice production by 20%-30%; the second breakthrough was the success in the research on hybrid rice in the mid-1970s, which increased the rice yield by about 20% on the basis of dwarf variety.
The two breakthroughs solved the food shortage issue in the developing countries including China. However, problems aggravated, including the abuse of chemical fertilizers and pesticides, soil degradation and environmental hazards.
"The starting point of the ‘Second Green Revolution’ should be counteracting the negative effects of the First Green Revolution. The goal of resources conservation and environment friendliness should be achieved through the breeding , technological promotion of new varieties and the reduction in the application of chemical fertilizers and pesticides, water and labor force."Zhang Qifa said.
Li Zhensheng, academician of the Chinese Academy of Sciences, proposed that we should prepare genetic resources for the Second Green Revolution, which won great support from the rice scientists. Rice breeding is expecting a third breakthrough.
Then, Zhang Qifa talked about his views on Green Super Rice. Li Zhikang, researcher of China Academy of Agriculture Sciences and Luo Lijun from Shanghai Agricultural Gene Center delivered their articles. They expounded Green Super Rice in terms of elements and technology from various aspects.
The research and cultivation of Green Super Rice call for hard work. Breeding new varieties of Green Super Rice can follow two-step strategy. First, transferring elite gene with green character from germplasm resources to excellent genetic background; second, Chromosome segments substitution lines or near-isogenic line hybridize with each other to realize gene pyramiding, so as to nurture the Green Super Rice combined with plenty of good genes.
The Practice of the Green Super Rice
From the very beginning, the Chinese Green Super Rice project was initiated to ensure food safety, water resources conservation and ecological environment protection, according to Yu Sibin.
Breeding new varieties of Green Super Rice of 863 Program (National High-tech R&D Program) was launched in 2010. Under the support of the program, Chinese rice research institutes cooperated with each other. They made use of the research achievement on rice functional genes to breed new varieties. Finally, they successfully bred new varieties or strains that are resistant to diseases and pests.
The new variety Huanghuazhan bred by Guangdong Academy of Agricultural Science has the characteristics of needing less chemical fertilizers and pesticides, water efficiency and drought resistance. Planted in Tuanfeng and Wuxue in Hubei Province, it’s estimated that each hectare of such rice can increase revenue of 6667.5 Yuan.
At present, the Green Super Rice developed by Chinese scientists gains the support from the Bill & Melinda Gates Foundation. The technology and new varieties of Green Super Rice will be brought to the Asian and African countries which are in need of food supply.
The characters of Green Super Rice still need to be optimized. Zhang Qifa said, the ideal condition is that the chemical fertilizers and pesticides will not be needed in the planting of the Green Super Rice. However, the current technology cannot meet such requirements.
To achieve this goal means that he and his team need to demystify more rice genes. “We want to compile a dictionary of rice genes. We just finish less than 10 percent of it. It needs continuous work”, Professor Zhang concluded.
