Effect of Foliar Application of Zinc and Boron on Fruit Growth, Yield and Quality of Winter Season Guava (Psidium guajava L.)

An experiment was conducted in 12 year old planted guava (Psidium guajava L.) garden at Kanpur (Uttar Pradesh) during the year 2014-15. The treatments comprised nine combinations of three ZnSO4 levels (0.50, 0.75, 1.00% solution) and three borax levels (0.2, 0.4, 0.6% solution) and one control of water spray. These 10 treatments were tested in factorial R.B.D. on guava. The results revealed that treated plants with Zn and Bo performed significantly much better than control of water spray in fruit growth, yield and quality traits. Among nutrient treatments, Zn So4 @ 0.75% or borax @ 0.4% spray increased fruit set percentage significantly over 0.50% Zn So4 or 0.2% borax spray, respectively but fruit retention percentage was recorded significantly highest with 1.00% Zn So4 or 0.6% borax solution spray. Fruit growth was influenced much by borax spray than Zn So4. The spray of 0.6% borax solution produced biggest size of fruits with maximum weight and volume which contributed to highest fruit yield of 45.17 kg/plant Zn So4 @ 1.00% spray produced 44.10 kg fruit yield/plant. Borax spray @ 0.6% solution attained significantly maximum values of 8.25% total sugar, 12.04 TSS brix, and 186.92 mg Ascorbic acid per 100g fruit. The treatment of Zn So4 @ 1.00% spray also recorded highest values of 6.83% total sugar, 11.64 TSS brix and 186.67 mg Ascorbic acid per 100g fruit but these values were found significantly higher only over 0.50% Zn So4 spray treatment.