Geographic patterns in fruit attributes for New Zealand grown kiwifruit

Fruit quality and maturity criteria have been developed for New Zealand kiwifruit to meet consumer requirements and minimise postharvest losses. Variation in fruit quality attributes occurs between orchards and growing regions. A better understanding of the factors that contribute to this variation is needed to assist the development of effective strategies for managing fruit quality. Phenotypic expression of fruit quality attributes, such as dry matter content and size, arise from the interaction of genotype and environment. Two commercial genotypes, Actinidia deliciosa var. deliciosa 'Hayward" and A. chinensis 'Hort16A', are cultivated over a range of environments in New Zealand. Where genotype is fixed, the phenotypic plasticity of a given attribute, such as fruit dry matter, is dependent on abiotic and biotic components of the environment that are either controlled or uncontrolled by growers. Environmental gradients within a production area, such as latitude, elevation, aspect or proximity to the coastline, have been implicated as a cause of product variability in fruit harvested from orchards. This paper uses data obtained from the industry maturity clearance process, for two genotypes, to assess the impact of management and geographic location of orchards within New Zealand on fruit size and dry matter content.