Relative Efficiency of Zinc Sulphate and Chelated Zinc on Zinc Biofortification of Rice Grains and Zinc Use-Efficiency in Basmati Rice

Abstract

Zinc deficiency in human nutrition is widespread in developing Asian and African countries where cereal grains are the staple food. Agronomic biofortification of Zn is a new innovative approach to get rid of Zn malnutrition from the poorest of the poor rural masses, who will never have money to buy mineral supplements nor can afford to improve the components of their diet by incorporating animal products. Hence, a field experiment was conducted during 2010 and 2011 on a sandy clay-loam soil (typic Ustochrept) at New Delhi, India to study the effect of NPK fertilization and to compare zinc sulphate heptahydrate (ZnSHH) and Zn–EDTA for growth, yield attributes, grain and straw yield, Zn concentration and uptake and Zn use efficiency in Basmati rice cultivar ‘Pusa Sugandh 5’ when applied to soil ZnSHH and Zn–EDTA were equally effective. Three foliar applications of ZnSHH increased Zn concentration and uptake by rice as compared to its soil application. Three foliar applications of Zn–EDTA (at tillering, booting and grain filling stages) was the best treatment and recorded significantly better growth, higher values for yield attributes, higher grain and straw yield and higher concentration and uptake of Zn in grain and straw of Basmati rice than soil application of ZnSHH or Zn–EDTA and two or a single foliar application of ZnSHH or Zn–EDTA. Three foliar applications of 0.5 % solution of Zn–EDTA recorded significantly higher head rice recovery than soil application. The highest KLBC, KLAC and KLER were obtained with three foliar applications of 0.5 % solution of Zn–EDTA.