OPTIMIZATION OF INTEGRATED NUTRIENT SUPPLY SYSTEM FOR STRAWBERRY (FRAGARIA × ANANASSA DUCH. 'CHANDLER') IN HIMACHAL PRADESH (INDIA)

Supply of deficit plant nutrients in sufficient quantity and appropriate proportion is one of the major factor controlling the yield and quality of fruits. Standardization for the extent of replacement of inorganic fertilizers through various organic and biological sources, without affecting the yield and fruit quality of strawberry crop at lower cost is the thrust and need of the hour. Farmyard manure and vermicompost were used as organic manures, whereas CAN, SSP and MOP were used as inorganic sources for the supply for N, P and K respectively. Azotobacter was inoculated at 2.0 kg/ha by dipping runner roots in culture slurry at the time of planting. Total recommended doses of organic and inorganic fertilizers (50 t/ha farmyard manure and 80, 40, 40 kg/ha N, P₂O₅ and K₂O respectively) were cumulatively calculated in terms N, P and K and supplied through different combinations of organic and inorganic sources. The treatment comprised of total nutrition through inorganic sources, 50% of the N requirement substitution through farmyard manure (0.5% N; 0.2% P₂O₅ and 0.5% K₂O) or vermicompost (1.0% N; 0.7% P₂O₅ and 0.8% K₂O) and added as basal doses and remaining half N through inorganic sources in one or two splits after crop stabilization. P and K were balanced through their inorganic sources and placed as basal. All these combinations were also taken with Azotobacter by inoculating runner roots in culture slurry. The majority of plant growth parameters, like number of crowns, number of runners, length of runners, number of plantlets and fruit characteristics like number of flowers, number of berries, fruit yield and net monetary return were recorded maximum in Azotobacter inoculated treatments with 50% N substitution by vermicompost and remaining 50% through inorganic fertilizer in two equal splits at establishment and before flowering stage. However, plant growth characters like height, spread and leaf area recorded maximum in inorganic fertilized plots. Characters like number of leaves per plant, duration of flowering, weight of berry, volume of berry and total phenol content remained unaffected by the nutritional treatments.