A Comparison in Fruit Sizing Among Early and Late Peach Varieties

Abstract

The time interval between fullbloom and fruit maturity for peach varieties varies. This variation has been shown to be due to the relative length of the three stages in the growth of the fruit (1, 2). Among early and late peach varieties, the duration of Stage I (a period of rapid fruit growth beginning at full-bloom, Figure 1) is nearly identical. Duration of Stage II (a period of retarded growth associated with embryo development), however, varies depending upon the earliness of the variety. Early varieties have the shortest Stage II and the least embryo development, while late varieties have the longest stage II and the most embryo development. Mid-season varieties are intermediate both in duration and the extent of embryo development. Variation among peach varieties in Stage III duration do exist, but these are not as closely related to earliness or lateness as are those in Stage II (1, 2). Since this work by H. Tukey, different peach varieties have become commerically important. Thus, it was of interest to relate these growth relationships with present day varieties.