Agronomic approaches to biofortify iron in tomato

The study was conducted to biofortify Fe in tomato fruit. Seven tomato varieties were tested in this study to screen out the potential variety for biofortification. Based on Fe concentrations of tomato fruit, BARI Tomato-14 was selected as test crop. Six different methods for Fe application viz. 100% as seedling priming, 50% in soil + 50% as foliar spray at seedling stage, 50% as seedling priming + 50% as foliar spray, 100% as foliar spray at seedling stage, 100% as foliar spray at flowering stage and 100% as foliar spray at fruiting stage @ 4 kg Fe ha-1. Iron was applied for 3 times at 7 day interval at all growth stages. Experiments were laid out in a completely randomized design (CRD) with 3 replications. Different application methods of Fe significantly influenced the growth, yield contributing characteristics, yield, biochemical constituents, nutrient concentrations and their uptake by BARI Tomato-14. The highest values of most of the studied parameters including Fe content and uptake were recorded from the application of 50% Fe as seedling priming + 50% Fe as foliar spray. Significant and positive correlations among the growth and yield contributing parameters due to the application of Fe were observed. Interestingly the highest vitamin-C, protein, lycopene, N, K and Ca contents and uptake were observed in 50% as seedling priming + 50% as foliar spray of Fe @ 4 kg ha-1. Except few most of the studied nutrients were negatively correlated with Fe. Iron was biofortified by 66.28 µg g-1 in BARI Tomato-14. Results suggest that application of 2 kg Fe ha-1 as seedling priming + 2 kg Fe ha-1 as foliar spray at seedling stage for 3 times at 7 days interval along with the recommended doses of NPK fertilizers in soil can be practiced for Fe biofortification in tomato.