Optimizing apple orchard management: Investigating the impact of planting density, training systems and fertigation levels on tree growth, yield and fruit quality

Abstract

An experiment was conducted to investigate the comprehensive influence of planting density, training system and fertigation level on the performance of 'Jeromine'/M.9 apple orchards at Dr. YS Parmar University of Horticulture and Forestry, Solan (India) in two consecutive years. Experiment encompasses 12 treatment combinations replicated thrice within a factorial experiment. The treatments included three planting densities (4000, 3200 and 2666 trees ha−1), two training systems (Tall Spindle and Vertical Axis), and two levels of fertigation (100 % and 75 % recommended dose of NPK). The results indicated that lowest planting density of 2666 trees ha−1 produced highest yield per tree accompanied with superior fruit quality. Trees planted at a planting density of 2666 trees ha−1 and trained to Tall Spindle training system notably restrained tree growth, with the latter contributing to higher yields and superior quality fruit. Similarly, 100 % recommended dose of NPK fertigation resulted in significantly higher yields and enhanced fruit quality. Remarkably, the three-way interaction analysis revealed that treatment combination of 2666 trees ha−1 planting density, Tall Spindle training system and 100 % recommended dose of NPK fertigation produced the highest yield of 13.6 kg tree−1, along with superior quality fruits. The study emphasized that increasing planting density decreased yield per tree while concurrently increasing yield per hectare. The most productive combination yielding 42.1 t ha−1, involved 4000 trees ha−1 with Tall Spindle training system and 100 % recommended dose of NPK fertigation. These findings provide valuable insights into optimizing apple orchard management strategies to achieve the delicate balance between tree growth, yield and fruit quality, assisting growers in making informed decisions for improved productivity and fruit quality, thereby contributing to the overall profitability of apple cultivation.