INFLUENCE OF TEMPERATURE ON BETWEEN-SEASON VARIATION IN DRY MATTER CONTENT OF 'HAYWARD' KIWIFRUIT

Consumers prefer 'Hayward' kiwifruit that have a high soluble solids concentration when the fruit are ripe. Since soluble solids concentration is highly correlated with the dry matter concentration (DMC) of fruit at harvest, DMC is now used as an indicator of fruit quality. The payment that New Zealand growers receive for kiwifruit increases with the DMC of the fruit. However, average DMC varies substantially from year to year and this variation is presumed to be linked to some aspect of climate. In this study, we show how the average DMC of fruit from several orchards in Te Puke varied from 16.3% to 17.4% during 7 growing seasons. This seasonal variation was highly correlated with variations in temperature. Cool weather during spring resulted in fruit having a low DMC while cool weather during summer resulted in higher DMC.