Protein and nutrient content in rice grain. Total grain protein (A) and N (B), P (C), K (D), Fe (E), Zn (F), S (G), and Mg (H) concentrations in mature seeds. Values are means ± SD of 10 biological replicates. DW, dry weight. *P ≤ 0.05; **P ≤ 0.01; Student t test.