Pre-harvest foliar application of calcium and boron influences physiological disorders,fruit yield and quality of strawberry (Fragaria × ananassa Duch.)

Studies were conducted in ‘Chandler’ strawberry to determine if pre-harvest foliar application of Ca, B or their combination influences physiological disorders, fruit yield and quality or not. For this, treatments consisted of (i) five sprays of calcium as CaCl₂ (first spray was performed at the petal fall stage and later at 7 days interval), (ii) three sprays of boron as boric acid (first spray at the beginning of flowering and later at 15 day interval), (iii) combination of (i) and (ii), and (iv) plants sprayed with water served as the control. Results indicated that fruit harvested from plants, which were sprayed either with Ca or Ca + B had significantly lesser incidence of albinism (6.7 and 6.5%), and grey mould (1.3 and 1.2%) than those harvested from plants sprayed either with B alone or in control. Although, B alone could not influence the incidence of albinism and grey mould, but it reduced fruit malformation (3.4 and 3.1%) significantly. Further, Ca, B or their combination had not influenced the individual berry weight, but marketable fruit yield differed significantly. The lowest marketable fruit yield (149.3 g/plant) was recorded in plants under control, and the highest (179.2 g/plant) in plants sprayed with Ca + B. Similarly, such fruit were firmer; had lower TSS, higher acidity and ascorbic acid content at harvest than those in control. Similarly, such fruit after 5 days storage were firmer and brighter, and have significantly lower TSS (7.9 and 7.8%); higher ascorbic acid content (43.7 and 45.0 mg/100 g pulp) and acidity (1.08 and 1.07%) than those in control or those receiving B alone. Incidence of grey mould was significantly lesser in fruit, which received Ca (2.2%) or Ca + B (1.9%) than those, which received either B (8.1%) alone or those in control (8.4%). Our studies indicated that pre-harvest foliar application of Ca + B is quite useful for reducing the incidence of disorders and getting higher marketable yield in ‘Chandler’ strawberry.