Effect of canopy position on fruit quality in 'Hort16A' kiwifruit in New Zealand

Canopies of 'Hort16A' kiwifruit vines [Actinidia chinensis Planch. var. chinensis] grown on a pergola were divided into six zones. two zones along the leader in a North-South direction, by three zones in an East-West direction, away from the central leader. Fruit quality was measured in each zone to determine if fruit from different positions were sufficiently different to warrant selective harvesting. Fruit weight, dry matter (DM) content, maturity (i.e., flesh colour, firmness, and soluble solids content), flesh nutrient content, and the incidence of storage disorders were measured. The experiments were carried out in three orchards in Northland, New Zealand, over 3 years. Fruit quality differences were detected between zones, but these differences were generally small and not always consistent over the three seasons. Fruit were 15 g larger in the zones furthest from the leader, in an East-West direction, and were likely to soften on the vine sooner than fruit closer to the leader, which were smaller with up to 0.39% higher DM content. Fruit further from the trunk, in a North-South direction, were : 4 g larger and more susceptible to physiological pitting during storage than fruit near the trunk, which were more susceptible to low temperature breakdown during storage. The results suggested that selective harvesting of 'Hort16A' fruit from different canopy positions is unwarranted for commercial producers in New Zealand.