Effects of Calcium Nitrate Application on Essential Soil Properties in Apple Plantation Grown under High Density Planting System

Calcium is an important mineral needed in the soil for the production of good quality apples. The investigation aimed to study effect of calcium nitrate soil application on some post-harvest soil properties in an apple plantation. Calcium nitrate soil application at the rate of 0 (control), 100, 200 and 300 gram per plant in two apple varieties Golden Delicious and Red Chief Camspur comprising 8 treatments with three replications were tested. Soil application of calcium nitrate increased organic carbon, cation exchange capacity, nitrogen, potassium and calcium availability with every enhanced dose in post-harvest soil, whereas available phosphorous, iron, zinc and boron with every enhanced dosage of calcium nitrate showed opposite trend and reduced availability of these nutrients in post-harvest soil. Soil organic carbon ranged from (0.788 to 0.852 %), CEC ranged from (15.0 to 18.0 cmol kg-1), Available N ranged from (258.5 to 268.1 kg ha-1), available P ranged from (14.78 to 16.29 kg ha-1), available K ranged from (303.7 to 310.7 kg ha-1), available Ca ranged from (1276.5 to 1370.3 ppm), Fe ranged from (43.778 to 47.552 ppm), available Zn ranged from (1.267 to 1.183 ppm), available boron ranged from (0.895 to 1.045 ppm). Among doses calcium nitrate soil application @ 300 gram per plant was superior to 200 or 100 gram per plant in both apple varieties. Golden Delicious performed better than Red Chief Camspur but variation was statistically non-significant. Results of research evidenced that calcium nitrate application reduced availability of soil phosphorous and micronutrients, thus mixture of micronutrients must be recommended to maintain availability of these elements to apple plant. Further studies under different ecologies and soil category need to be carried for finding threshold limits of calcium dosage as per plant establishment, moisture variability and plant age.