Improving human micronutrient nutrition through biofortification in the soil–plant system: China as a case study

Abstract

Micronutrient malnutrition is a major health problem in China. According to a national nutritional survey, approximately 24% of all Chinese children suffer from a serious deficiency of iron (Fe) (anemia), while over 50% show a sub-clinical level of zinc (Zn) deficiency. More than 374 million people in China suffer from goiter disease, which is related to iodine (I) deficiency, and approximately 20% of the Chinese population are affected by selenium (Se) deficiency. Micronutrient malnutrition in humans is derived from deficiencies of these elements in soils and foods. In China, approximately 40% of the total land area is deficient in Fe and Zn. Keshan and Kaschin-Beck diseases always appear in regions where the soil content of Se in low. The soil-plant system is instrumental to human nutrition and forms the basis of the "food chain" in which there is micronutrient cycling, resulting in an ecologically sound and sustainable flow of micronutrients. Soil-plant system strategies that have been adopted to improve human micronutrient nutrition mainly include: (1) exploiting micronutrient-dense crop genotypes by studying the physiology and genetics of micronutrient flow from soils to the edible parts of crops; (2) improving micronutrient bioavailability through a better knowledge of the mechanisms of the enhancers' production and accumulation in edible parts and its regulation through soil-plant system; (3) improving our knowledge of the relationship between the content and bioavailability of micronutrients in soils and those in edible crop products for better human nutrition; (4) developing special micronutrient fertilizers and integrated nutrient management technologies for increasing both the density of the micronutrients in the edible parts of plants and their bioavailability to humans.

The effects of selenium and other micronutrients on the antioxidant activities and yield of corn (Zea mays L.) under drought stress

“…It is likely that the presence of each may interrupt the functioning of the other (Singh and Singh 1978;Yang et al 2007). …”

Long-term experiments for sustainable nutrient management in China. A review

“…Tang (1996) reported that 46% of Chinese farmland was deficient in secondary nutrients, with Ca-and S-deficient soils being about 20%, and Mg-deficient soils being about 4%. More than 50% of soils in China have DTPA-extractable Zn contents of less than 1.0 mg kg −1 (Yang et al, 2007). Lin et al (2008) estimated that about 160 M ha of farmland soil were deficient in certain micronutrients, but only 11.1% received micronutrients from chemical fertilizer application.…”

Zinc fertilization effects on agromorphological and quality parameters of commonly grown rice

“…Results also showed that Zn content in brown rice varied significantly not only among the cultivars but also within the different categories of the cultivars. Most of the aromatic rice species, such as Jasmine and Basmati types, are high in both Fe and Zn (Senasdhira and Graham, 1999;Graham et al, 1999;Yang et al, 2007). Methods of Zn applications also showed significant variation between them and its magnitude was higher with soil plus foliar application of Zn than only soil application irrespective of the cultivars grown.…”