Efficacy of foliar application of nutrients on yield and quality of guava

Aim: To assess the efficacy of foliar application of nutrients, i.e., calcium as calcium chloride and boron as borax on yield and quality of guava (Psidium guajava L.) cv. Lalit fruits. Methodology: Nineteen -year- old uniform guava plants planted at 6x6 m apart were selected for investigation. Foliar application of calcium chloride (CaCl4) and borax (Na-2 [B4O5 (OH)(4)]center dot 8H(4)O) was done as split dose application during first week of August and second week of September in the year 2017 and 2018. Nine treatments in toto viz., T-0 (Control), T-1 (Calcium chloride 0.1%), T-2 (Calcium chloride 0.2%), T-3 (Borax, 0.1%), T-4 (Borax 0.2%), T-5 (Calcium chloride 0.1% + Borax 0.1%), T-6 (Calcium chloride 0.1% + Borax 0.2%), T-7 (Calcium chloride 0.2% + Borax 0.1%), T-8 (Calcium chloride 0.2% + Borax 0.2%) were applied as foliar feeding. Effect of treatments was recorded on fruit length, fruit width, fruit volume, fruit yield (kg tree(-1)), fruit specific gravity, total soluble solids, acidity, ascorbic acid, total sugar, reducing sugar and non-reducing sugar content of fruit. Results: Foliar application of calcium chloride @ 0.2% along with borax @ 0.1% was the best treatment combination among the all treatments for improving fruit yield (i.e., from 44.333 kg tree(-1) to 61.170 kg tree(-1)) and quality of guava fruits (viz., TSS 7.613 - 11.670 (0)Brix, ascorbic acid 155.457 - 176.343 mg 100g(-1) pulp and total sugars 5.383 - 7.547%) in the environmental conditions akin to environmental conditions of Horticultural Research Farm of Babasaheb Bhimrao Ambedkar University, Lucknow (India). Interpretation: Judicious application of calcium and boron as foliar spray might ameliorate adverse effects of soil and environmental factors and improve production and quality of guava fruits.