Over 4 years, using estimates of fruit dry weight derived from diameter measurements in situ, cultivar variation in apple fruit relative growth rate (RGR) in the period following June drop was evident. These differences diminished as the season progressed however. Using estimates of dry weight per cell, fruit cell absolute growth rate increased over time and RGR showed no clear pattern in contrast to the RGR of whole fruit. There were no cultivar differences in carbohydrate allocation among the soluble, starch, and remaining ethanol-insoluble, non-hydrolyzable pools irrespective of cultivar RGR. The storage carbohydrate pool comprised an increasing fraction of the total dry weight over time with the starch pool comprising 10 to 25% of the storage carbohydrate, varying with season and cultivar. Neither fruit competition within a cluster nor post-June drop thinning altered fruit RGR or carbohydrate allocation patterns when compared to fruit thinned post-bloom.
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