Changing scenario of micronutrient deficiencies in India during four decades and its impact on crop responses and nutritional health of human and animals

Changing scenario of micronutrient deficiencies phase wise during four decades (1968-2008) was studied in soils of India, their impact of crop production and changes in micronutrient concentration in seeds and fodders, thereby influences on animal and human health. Results of 269,000 soil sample analysis revealed that mean deficiency of zinc, iron, copper, manganese, boron, molybdenum was found in 49, 12, 3, 5, 33 and 13% samples, respectively. Throughout country, zinc deficiency is increasing except Punjab, Haryana and Uttar Pradesh.where zinc deficiency is declining from initial 70-90 percent in Punjab and Haryana to the level of 13-20 percent due to regular application of zinc sulphate. On the other hand, deficiency of zinc has increased in southern states due to extensive use of multi micronutrient mixtures containing less zinc. Periodic assessment of soil data also suggests that zinc deficiency in soils of India is likely to increase from 49% to 63% by the year 2025 as most of the marginal soils brought under cultivation are showing zinc deficiency. In states like Gujarat, Bihar and Madhya Pradesh zinc deficiency is found almost stagnant during four decades despite much efforts have gone to popularize zinc application in various crops. Zinc deficiency is increasing in soils, so zinc content in seed and in blood plasma of animal and humans is decreasing. In Haryana and Punjab, zinc concentration in grains of wheat is improving from 23 to 72 mg kg-1. Farming family consuming their crop produce from zinc deficient farms had low zinc in their blood plasma compared to those which were fed on produce received from farms fertilized with zinc regularly. Similarly improvement in zinc fertility in Dahima village in Haryana resulted in adequate level of zinc in staple grains, fodder, blood plasma of humans and animals. Fodders in Haryana showed copper deficiency instead of zinc. Manganese concentration in grains and fodders was found low in Bihar and Punjab. Zinc supplementation is therefore essential for maintaining high zinc content in soil, seed and blood plasma of human and animals.