At present, there are two sources of selenium rich vegetables and selenium rich grains promoted internationally: one is to plant in the soil of selenium rich areas, and the other is to artificially apply exogenous selenium in the planting process. On November 22, the "on-site observation meeting of new varieties of selenium efficient vegetable rape" co sponsored by the oil Institute of the Chinese Academy of Agricultural Sciences and the national rape industry technology system in Wuhan showed the world's first selenium efficient vegetable hybrid "selenium Ziyuan 1" cultivated by Academician Wang Hanzhong of the oil Institute of the Chinese Academy of Agricultural Sciences. This will be a new way for us to easily obtain the source of selenium.
Although selenium accounts for less than 1 / 100000 of the total weight of the human body, it is an essential element for maintaining health. It is known as the "fire of life", "the patron saint of the heart", "the guardian of the liver", "the king of anti-cancer", "longevity element" and "natural antidote". The Chinese Nutrition Society recommends a daily selenium intake of 50-250 micrograms for adults, and the U.S. Government recommends a daily selenium intake of 200 micrograms per person. However, due to the lack of selenium in soil, the average daily selenium intake of adults in China is only 26-32 micrograms.
Taking selenium fortified medicinal and food preparations is the main way to supplement selenium at present, but these medicinal and food preparations have low utilization rate in human body and risk of side effects. Selenium rich vegetables and selenium rich Cereals, as important organic selenium converters, are the safest, effective, cheap and feasible way for human intake of selenium. However, China's green selenium rich land only accounts for about 3.5% of cultivated land, and the application of exogenous selenium has a great negative impact on the environment, which is easy to cause secondary pollution.
By comparing the total nutritional quality of more than 100 rape bolts with 9 common vegetables (4-6 varieties of each vegetable), Academician Wang Hanzhong team found that rape bolts have a special enrichment function of selenium, and their selenium content is significantly higher than that of other vegetables. Vegetables with selenium content of 0.01-0.1 mg / kg are regarded as selenium rich vegetables. In non selenium rich soil without exogenous selenium, the selenium content of rape bolt is distributed in the range of 0.009-0.074 mg / kg, indicating that there is great potential to improve the selenium content of rape varieties.
Based on the field planting identification of soils in various regions of the country, Academician Wang Hanzhong's team took the lead in discovering the phenomenon of "selenium efficiency" and defined the concept of "selenium efficiency" rape, that is, in non selenium rich soil with soil pH value of 4.5-6.0 and selenium content greater than 0.16mg/kg, or in non selenium rich soil with soil pH of 6.0-8.5 and selenium content greater than 0.11mg/kg, Selenium enriched rape stalks with fresh weight selenium content greater than 0.01mg/kg were produced without exogenous selenium, which was a 'selenium efficient' rape.
Relying on the excellent germplasm resources discovered, Academician Wang Hanzhong's team successfully bred the world's first selenium efficient vegetable Hybrid 'selenium Ziyuan 1' by using modern breeding methods such as polymerization hybridization, microspore cultivation and molecular marker assisted selection. " Selenium Ziyuan No. 1 'has strong selenium enrichment capacity. It is planted in many non selenium rich soils in China. Its rape bolt selenium content is between 0.01-0.07mg/kg. It also has the characteristics of high calcium, high vitamin C, high amino acid and high zinc. It is rich in nutrition, green color, crisp and tender taste, and has great potential for the development of medical and health care efficacy.' Selenium Ziyuan 1 'can be picked 2 months after sowing, and 3-4 crops can be picked at a time. The yield per mu can reach 600-800 kg. Supporting close planting cultivation measures can achieve higher yield.