Biofortification of rice grain with zinc through zinc fertilization in different countries
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Increasing zinc (Zn) concentration of rice seed has potential benefits for human nutrition and health. Enhanced levels of Zn in grain also contributes greatly to crop production through better germination and seedling vigor of rice plants grown on soils with limited Zn supply.
Aims and methods
This study evaluated the effect of soil and/or foliar Zn fertilizer application on grain yield and grain Zn concentration of rice grown in 17 field trials conducted in 2008 to 2010 in China, India, Lao PDR, Thailand and Turkey on soils ranging in pH from 4.8 to 8.8 and DTPA- extractable Zn from 0.5 to 6.5 mg kg−1.
Zinc fertilization had little effect on rice grain yield with the exception of increases of up to 10 % in some locations in China and India. As an average of all trials, Zn application increased grain yield by about 5 %. Grain Zn concentrations were, however, more effectively increased by Zn fertilization, especially with foliar Zn applications. On average, Zn concentration in brown rice (whole caryopsis with husk removed) was increased by 25 % and 32 % by foliar and foliar + soil Zn applications, respectively, and only 2.4 % by soil Zn application. The Zn concentration of un-husked rice (whole grain with husk), which was increased by 66 % by foliar Zn, showed a close association with the Zn in brown and white rice, indicating a possible penetration of Zn from the husk into the inner layers of the rice endosperm. Increase in grain Zn concentration by foliar Zn spray was significantly affected by the timing of the foliar application. More distinct increases in grain Zn by foliar Zn application were achieved when Zn was applied after flowering time, e.g., at early milk plus dough stages.
Foliar Zn spray offers a practical and useful means for an effective biofortification of rice grain with Zn. This practice consistently and significantly contributed to increases in grain Zn of rice irrespective of cultivars, environmental conditions and management practices in 5 different countries.
KeywordsBiofortification Foliar spray Rice Zinc deficiency
This study was financially supported by the HarvestPlus Program (www.harvestplus.org) and the sponsors of the HarvestPlus Global Zinc Fertilizer Project-I. Phase (www.harvestzinc.org) including Mosaic Company, K + S Kali GmbH, International Zinc Association, Omex Agrifluids, International Fertilizer Industry Association and International Plant Nutrition Institute.
- Gomez-Becerra HF, Abugalieva A, Morgounov A, Abdullayev K, Bekenova L, Yessimbekova M, Sereda G, Shpigun S, Tsygankov V, Zelenskiy Y, Pena RJ, Cakmak I (2010a) Phenotypic correlations, G x E interactions and broad sense heritability analysis of grain and flour quality characteristics in high latitude spring bread wheats from Kazakhstan and Siberia. Euphytica 171:23–38CrossRefGoogle Scholar
- Hotz C, Brown KH (2004) Assessment of the risk of zinc deficiency in populations and options for its control. Food Nutr Bull 25:94–204Google Scholar
- Randhawa NS, Sinha MK, Takkar PN (1978) Micronutrients. In: Soils and rice, International Rice Research Institute, pp. 581–603Google Scholar
- Sims JT, Johnson GV (1991) Micronutrient soil tests. In: Mortvedt JJ, Cox FR, Shuman LM, Welch RM (eds) Micronutrients in agriculture: second edition. Soil Science Society of America Book Series. Soil Science Society of America, Inc, Madison, pp 427–476Google Scholar
- Stein AJ, Nestel P, Meenakshi JV, Waim M, Sachdev HPS, Bhutta ZA (2007) Plant breeding to control zinc deficiency in India: how cost-effective is biofortification? Publ Health Nutr 10:492–501Google Scholar
- Zhang YQ, Shi RL, Karim MR, Zhang FS, Zou CQ (2010) Iron and zinc concentrations in grain and flour of winter wheat as affected by foliar application. J Agric Food Chem 58:12268–12274Google Scholar