Calcium analysis and the prediction of bitter pit in apple fruit

Calcium concentrations of Cox's Orange Pippin apple fruit, determined on plugs of cortical tissue, measured in fruit 3 weeks before commercial harvest, and in different districts, different seasons, and by 2 laboratories, were found to be closely related to subsequent development of bitter pit. Data from an extensive survey in Nelson orchards showed that calcium analyses before harvest could be used reliably to predict the risk of bitter pit developing in any line of fruit.