Influence of zinc and boron supplement upon some trace nutrients deposition in rice grain

Rice is major cereal crop of Pakistan and staple food of rest of world. The nutritional enriched rice grain is demanded by exporting countries and the consumers. The objective of nutritional rice may be achieved by ensuring judicious supply of fertilizers followed by application of good field practices. In order to investigate the influence of Zinc (Zn) and Boron (B) supplement applied along with recommended doses of Nitrogen (N) and Phosporous (P) upon health required trace nutrient accumulation into rice grain, the experiment was conducted. Five varieties (IR6, IR8, DR92, DR83 and Shahkar) were selected for the study. Soils of the experimental field were clayey in texture (clay > 52.75 %), non-saline (E.C < 0.40 dSm-1), moderately alkaline (pH:8.12) and deficient in organic matter contents and trace nutrients viz. B: 0.7 µgg-1; Zn:0.46µgg-1:Cu: 0.56µgg-1 ; Fe: 0.59 µgg-1and Mn: 0.91 at both the depths (0-15 and 15-30cm). Addition zinc sulphate (ZnSO4) as Zn source and Boric acid (H3PO3) as B source were applied. Result of the study indicated that influence of the treatment and variety upon Zn, B, Copper (Cu) and Iron (Fe) contents in grain with difference of magnitude was found to be highly significant (P<0.001) whereas upon Mn it was found to be significant at (P<0.01). It was concluded that not only the supplement of Zn at 10 Kgha-1 but B at 2 Kgha-1 along with N at 135 KgHa-1 and P at 90 KgHa-1 are necessarily required in flooded rice regimes to obtain nutritional grain. Key words: Rice, Nutrition, Trace elements, Zinc, Boron, supplement