Effect of plant bio stimulant application on plant health, growth, fruit yield and quality of apple (Malus x domestica) under temperate conditions of Jammu and Kashmir, India

Abstract

A research trial was conducted to study the efficacy of commercial product G5 granules and liquid (a plant bio stimulant consisting of sea weed extract, amino acids, herbal extract, humic acid and anti-fungal substances) on plant health, growth, fruit yield and quality attributes of apple cv. Red Delicious under temperate conditions of Jammu and Kashmir during the year 2022-23. The treatments comprised: T1 (soil application of G5 granules @500 g/tree as basal dose at pre-flowering stage), T2 (T1 + G5 liquid @250 ml/100 l of water as foliar spray at petal fall stage), T3 (T2 + G5 liquid @250 ml/100 l of water as foliar spray at walnut size stage), T4 (T3+G5 liquid @250 ml/100 l of water as foliar spray at fruit development stage) and T5 (control) in addition to standard recommendations. Results of study showed that the highest growth in terms of shoot length was obtained in T4 followed by T3, T2 and T1 treatments. The highest fruit set was observed in treatment T2 that was statistically at par with T3 and T4. T4 recorded the highest fruit retention, fruit yield and the lowest fruit drop. The lowest growth, fruit set, fruit retention, fruit yield and the highest fruit drop was observed in control. All treatments were found to be highly superior to control in terms of fruit weight, length, breadth and firmness with T3 and T4 showing marked increase in fruit colour as compared to other treatments. As regards chemical fruit quality attributes, again T4 recorded the highest TSS, reducing sugars and total sugars while the values of these attributes were the lowest in control and vice versa for acidity. There was no apparent phyto-toxic effect of any of the treatments on tree/fruit health. Thus, treatment T4 (soil application of G5 granules as basal dose @500 g/tree at pre-flowering stage + G5 liquid foliar sprays @250ml/100 l of water one each at petal fall, walnut size and fruit development stage) was found to be the best among all treatments in enhancing growth, fruit yield and quality attributes of apple.