Agronomic Performance of Tomato to Calcium and Magnesium Sulphate Amendments under Alluvial Plains of Punjab

Abstract

Punjab region’s crop productivity potential and soil health has been compromised through the continual NPK and imbalance secondary nutrients application. Decreased application of secondary and micronutrients have resulted in severe nutritional deficiencies in crop and soil, and therefore, lowered the overall crop productivity. For investigation, open field experiments were conducted during 2022–23 and 2023–24 under randomized block design (RBD) at research farm, UIAS to evaluate the tomato growth performance and nutrients uptake to varying levels of CaSO4 (75 and 150 kg) and MgSO4 (50 and 100 kg) amended with NPK sources (Urea, SSP and MOP). Nine treatments with three replications comprised of varying Ca and Mg levels along with NPK sources have been selected and tested for two years. Results showed that the Ca and Mg based treatments showed high vigor in improving the crop growth and improved the soil nutrients pool. T5 (100% RDN NPK + Mg @ 100 kg ha-1) showed its supremacy over the other treatments with maximum plant height of 199.73 cm at maturity, fruit/plant (27.64 and 28.51 kg), yield/plant (2.64 and 2.99 kg) and fruit yield/100 m2 (1056.96 and 1081.29 kg). Similar treatment (T5) significantly improved the leaf and fruit NPK content over the sole NPK based treatment. Data on leaf and fruit Ca and Mg content revealed that maximum leaf Ca (2.27 and 2.29%) in T4, fruit Ca (2.16 and 2.18%) in T3, leaf Mg (1.26 and 1.29%) and fruit Mg (0.41 and 0.45%) was recorded under T7 treatment. Moreover, T7 treatment also showed its potential with highest Ca and Mg accumulation of 491.42 and 253.98 ppm in soil in respective years. Therefore, the study identified the T5 and T7 treatments as potent returning higher crop production and quality indices and also restored the soil with balanced Ca: Mg ratios along with other nutrients.