Effect of increased preharvest temperature on fruit quality of kiwifruit(Actinidia deliciosa)

SummaryRelocatable greenhouses were used to increase the air temperature around mature kiwifruit vines 3–4 degrees C above ambient temperature during the period of fruit maturation on the vine. Fruit grown under increased temperatures, between mid-March and mid-May, had lower soluble solids concentrations but had higher starch concentrations in both core and cortex tissue. After long-term storage for 20 weeks, concentrations of soluble solids in fruit grown under increased temperature were higher than those of control fruit. Flesh firmness of fruit from different temperature regimes was similar during maturation on the vine, but fruit which had matured under the increased temperature remained firmer than control fruit during cool storage. When only half the vine was covered with a greenhouse, there was evidence of translocation of nutrients between the two halves of the vine.