Title: Preharvest Fruit Analysis as a Predictor of D'Anjou Pear and Yellow Newtown Apple Physiological Disorders, Storage Quality and Ripening Behavior

Regression equations associating the preharvest mineral status of fruit with the occurrence of physiological disorders were used to predict the occurrence of bitter pit (BP) and internal breakdown (IB) on Newtown apples and cork spot on D'Anjou pear fruits up to 60 days before harvest in two years. Equations for a given year were applied to data from the other. Twenty and ten orchards in 1982 and 1983, respectively, were sampled and analyzed for Ca, P, K, N, Mg, Mn, Fe, Zn, B, S, Na and Se. There were higher bitter pit and cork spot incidence after storage than at harvest. In Newtown apples, fruit Ca, fruit weight, and wt/Ca ratio accounted for the most consistent predictive factors. Bitter pit could be predicted 20 days before commercial harvest. Internal breakdown could be predicted from fruit sampling data 60 days before harvest. Fruit Ca and the ratios wt/Ca and N/Ca accounted for the most consistent predictive tools for cork spot in D'Anjou pears