Studies on nutrient management in apple cv. Oregon Spur-II under the cold desert region of Himachal Pradesh in India

Abstract

The productivity of apple is restrained by many factors, of which the mineral nutrition is the most significant one and no single source of nutrients is capable of supplying the plant nutrients in ample proportion to augment productivity. A field experiment was carried out during 2014-16 to study the effect of integrated nutrient system in apple at Regional Horticultural Research Sub Station Tabo (Spiti), Himachal Pradesh. In this trial, twelve years old uniform and healthy trees of apple cv. Oregon Spur-II on contour system at 3 m apart were selected. The experiment consist of nine treatments, viz., T1, 75% NPK; T2, 100% NPK; T3, 125% NPK; T4, 50% NPK+10 kg vermicompost/plant; T5, 75% NPK+10 kg vermicompost/plant; T6, 100% NPK+10 kg vermicompost/plant; T7, 50% NPK+10 kg vermicompost/plant + biofertilizers; T8, 75% NPK+10 kg vermicompost/plant + biofertilizers; T9, 100% NPK+10 kg vermicompost/plant + biofertilizers; and replicated thrice under randomized block design. Nitrogen applied in two split doses, half before flowering along with the full dose of phosphorus, potassium, vermicompost, biofertilizers and remaining half nitrogen one month after first application. Application of 100% NPK+10 kg Vermicompost/plant along with biofertilizer inoculation significantly increased leaf area (41.31 cm2), plant height (227.3 cm), plant spread (127 cm N-S and 124.3 cm E-W), trunk girth (60 mm), shoot growth (43.64 cm), fruit set (59.41%), fruit/tree (97 No), fruit weight (236.3g), TSS (12.03°Brix), fruit yield (22.93kg/tree), leaf nitrogen (2.95%), phosphorus (0.52 %) and potassium (1.54 %). The higher growth attributes might have increased interception, absorption and utilisation of radiant energy which in turn increased overall growth, fruiting and leaf nutrient status. Moreover, better nutrient uptake and carbohydrate accumulation in leaves, resulting in healthy leaf growth, plant spread improved significantly with inoculation of biofertilizers due to increased cell metabolism resulting from enhanced enzyme activity, chlorophyll content and photosynthetic processes.