Iron and Zinc Biofortification Strategies for Improving Rice Seedling Vigour and Grain Quality

Rice (Oryza sativa L.) is a staple crop in Southeast Asia, grown with heavy applications of primary nutrients, which leads to deficiencies in essential micronutrients such as iron and zinc. Micronutrient biofortification through nutripriming, soil application and foliar application offers a promising approach to enhance their concentration and seedling vigour in rice. An experiment was conducted using Telangana Sona (RNR-15048) to evaluate the effects of iron and zinc nutrition on seedling growth and micronutrient status under dry direct-seeded rice conditions. In the laboratory study, nutripriming with FeSO₄ + ZnSO₄ significantly improved germination percentage, shoot length, root length and seedling vigour index at 7 and 14 days after incubation compared with the control. In the field experiment, combined application of iron and zinc through seed priming, soil application or foliar application significantly increased iron and zinc content in rice foliage and grains. Higher iron and zinc concentrations in grain were recorded with foliar application of FeSO₄ + ZnSO₄ at the panicle initiation stage. The study indicated that integration of iron and zinc application effectively improved seedling vigour, micronutrient accumulation and grain nutritional quality in dry direct-seeded rice.