The problem of cadmium pollution in rice has once been talked about "cadmium" color change. Now, the integrated innovation experts of Hunan Academy of agricultural sciences through genome editing technology and utilization technology of rice heterosis, take the lead in establishing the technical system of breeding parents and combination of low CD in Indica Hybrid Rice in the world, the key genes of rice cadmium uptake by site directed mutagenesis, thus effectively blocking the absorption of cadmium in rice, cadmium the content of rice plants. So, what is the harm of cadmium to the human body? How does the problem of cadmium in rice be caused? Will the newly developed low cadmium rice affect the growth and yield of rice? When can low cadmium rice be applied and popularized in large area?
What are the main hazards of cadmium to the human body?
Cadmium is exceed the standard attention, mainly because of cadmium is a heavy metal, harmful to the human body once ingested, it will be up to the half life of 10-30 years, will be continuously enriched in bones and kidney etc, cause osteoporosis, renal failure, cancer and cardiovascular disease.
How is the problem of cadmium in rice produced?
The cause of excessive cadmium in rice is not single. Besides the cadmium content in the soil, along with the development of industrialization in China, the discharge of wastewater and exhaust gas from mining and smelting, and the application of cadmium and phosphate fertilizer cause the Cd pollution of cultivated land. According to statistics, 13 million hectares of cultivated land in China are contaminated with cadmium. Rice is not only one of the main grain crops in China, but also one of the crops that easily accumulate cadmium. The cadmium in the paddy field is absorbed by the roots of rice and transported to the stems, leaves and rice. Southern China due to the acidic red soil is widely distributed (available cadmium content in high acidic soil), planting pattern based (japonica indica indica rice cadmium accumulation in most relatively stronger), increased rice cadmium pollution risk.
Does low cadmium rice affect the growth of rice?
Because cadmium is not essential plant mineral elements, generally there is no specific rice cadmium uptake gene in rice, and cadmium are absorbed by manganese and other essential mineral elements by being absorbed into the roots, so the low cadmium rice in cadmium absorption at the same time, will affect the absorption of manganese.
Since low cadmium rice can affect the absorption of manganese in rice, does that affect the growth of rice? Manganese is a necessary trace element in plants. It does not require a large amount of manganese to maintain the normal growth of rice. The rice has a lot of time in the whole growth period are planted in the flooded state, in the soil conditions, Mn content is higher, so the content of manganese in general under the condition of planting rice will far exceed its normal growth and development needs, at the same time, bring the toxic effects of high manganese content in rice has evolved a series of mechanisms to lift the body of the. Therefore, even under normal cultivation conditions, the growth of rice will not be affected, even if the manganese content of low cadmium rice is greatly reduced.
When can low cadmium rice be applied and popularized in large area?
At present, low cadmium rice also needs to be tested and demonstrated under different ecological and soil conditions. If the policy is licensed, it will achieve large scale application in 2-3 years. In addition, low cadmium rice decreased cadmium content can also try to use technology to other crops, but need to test and evaluation. (Gao Liming)
(source: People's Network - the source of popular science in China: Hunan Academy of Agricultural Sciences)