ZINC BIOFORTIFICATION OF CEREALS THROUGH FERTILIZERS: RECENT ADVANCES an‎d FUTURE PERSPECTIVES

Zinc (Zn) is a micronutrient, essentially required by plants, animals and humans. Zn deficiencyin humansdue to the consumption of food with inadequate Zn contentis of global concern.Approximately, one third of poor world’s population is at high risk of Zn deficiency due to its reliance on cereals for daily caloric requirements.The cereals, generally grown on calcareous soils have low grain Zn. The major reason of lowerZn content incereals ispoor Zn bioavailabilityinduced by various soil and/or crop management factors.The factors responsible for low grain Zn are high soil pH, low organic matter, salinity/alkalinity,water logging, and poorly managed soil fertility.Due to its critical role in growth and developmentofhumans, food with adequate Zn content is mandatory.This situation demandssome effective strategiesfor theenhancement ofgrain Zn contenttoovercome human Zn deficiency. Zincsupplementation of food, Zn pills, breeding of high Zn uptake species,and biofortification through fertilizers are being employed to address the issue.Among all strategies,Zn biofortificationthrough fertilizersis an effective and economical technique. Mineral Zn fertilizersare applied alone or in combination withorganic and biofertilizers. Integrated use ofmineral, organic and biofertilizersimprovesZn uptake and assimilation in cerealsgrains. Nanotechnology and enrichment/coating techniques are also effective to enhance grains Zn.This review critically discuss the efficiencyof various strategies to promote Zn availability and uptake by plants that assurefood and nutrition security.Zn enriched/coated urea is considered an effectivetoolto ensure crops with optimum concentration of Zn for human consumption.