Abstract
In a controlled nutritional experiment, the percentage of fruit showing cork spot was significantly negatively correlated with the concn of Ca in leaves and in the flesh of the fruit. With NO-3 N, fruit Ca increased more rapidly in proportion to leaf Ca than with 3/4 of the N supplied as NH4. To assure commercial control of cork spot, flesh Ca must be above 200 ppm dry wt. To consistently attain this level in the fruit, leaf Ca in late August must be above 1.90 percent dry wt. The wide range in incidence of cork spot at a given level of fruit Ca indicates that high Ca in the fruit may decrease or prevent this disorder but the causal factor is not the lack of Ca.

This publication has 0 references indexed in Scilit: