The Effects of Calcium on the Ultrastructure of Cox's Orange Apples With Reference to Bitter Pit Disorder

Abstract

An electron microscope study on thin sections of epidermal, hypodermal and cortical tissues has been made of calcium-sprayed and unsprayed apples in relation to bitter pit disorder. Golgi bodies, endoplasmic reticulum, mitochondria, chromoplasts, vacuoles and groundplasm were better preserved in sprayed apples during cool storage for up to 2 months than in unsprayed samples. In unsprayed apples these organelles were often drastically changed. The nucleus remained reasonably well preserved in all samples. Apples from trees sprayed only once gave somewhat intermediate results.