Calcium Nutrition for Improving the Growth and Yield of Carrot in Acid Soils

Abstract

Aims: To evaluate the effect of various sources, levels and methods of calcium application on the growth, yield and SPAD index of carrots grown on acid soils
 Study Design: Factorial randomized block design (FRBD) with three replications.
 Place and Duration of Study: A field experiment was conducted in the farmer’s field at Takkarbaba Nagar, Ooty from February to June, 2023.
 Methodology: A field experiment was conducted with carrot hybrid Zubera using lime at 50% LR and dolomite at 20,40,60 and 80 kg Ca ha-1 as basal soil application and foliar spraying of 0.5% calcium EDTA and calcium citrate twice on 30 and 45 DAP in a factorial randomized block design with three replications. The growth parameters such as plant height, petiole length, number of leaves per plant, SPAD index and tuber yield were recorded as per standard protocols at different plant growth stages viz., vegetative, tuber development and harvest stages.
 Results: A significant linear increase in plant height, petiole length, number of leaves per plant, SPAD index and tuber yield was recorded with the supplementation of calcium at different levels. Higher plant height (26.3 cm, 51.2 cm and 56.1 cm), petiole length (13.8 cm, 23.0 cm and 35.8 cm), number of leaves per plant (7.62, 7.82 and 9.30), SPAD index (22.0, 38.0 and 35.2) and fresh tuber yield (37.2 t ha-1) was registered with NPK+ 80 kg Ca as dolomite along with two sprays of 0.5% Ca EDTA twice which was followed by the same level of calcium as dolomite + foliar spraying of 0.5% calcium citrate twice. The minimum growth and yield response of carrot at all the growth stages was noticed with NPK control.
 Conclusion: Application of calcium through soil and foliar spraying showed synergistic influence on the growth and SPAD index of carrot at all stages of growth. Application of NPK+ 80 kg Ca ha-1 as dolomite performed better when compared to lime applied at 50% LR. Between Ca EDTA and Ca citrate, the performance of Ca EDTA was better in improving the growth and yield of carrot. It was concluded that the combined application of soil test based NPK+80 kg Ca ha-1 as dolomite along with two sprays of 0.5% calcium EDTA on 30 and 45 DAP would be effective in improving the growth, yield and SPAD index of carrot grown on acid lateritic soils.