Temperature requirements for growth and ripening of apples.

Abstract

The effect of temperature on the growth and ripening of fruits of up to ten cultivars grown at 4 different sites (2 in Netherlands, 1 in German Federal Republic and 1 in Denmark) was studied using a simple model. The period between flowering and harvest could be divided into 3 phases of differing temperature response. In most cases the first month after the beginning of the flowering and the period immediately before harvest showed a positive reaction towards high temperatures. During the period in between, which varied from 1-2 months in early cultivars to 5-6 months in late ones, no temperature effects were found in most cultivars. Temperature sums found in the first and third response periods did not show any relationship with earliness or lateness of crops. On the contrary, early and late cultivars had appoximately the same sums. Base monthly temperatures accounted for 0 to 89% of the differences in days between the different phases of growth of a fruit on the tree. (Abstract retrieved from CAB Abstracts by CABI’s permission)