Fruit Cracking of a Susceptible, an Intermediate, and a Resistant Sweet Cherry Cultivar

Abstract

Fruit were studied to determine if anatomical and physiological features explain the difference in susceptibility to rain-induced cracking of the sweet cherry (Prunus avium L.) cultivars Sue (resistant), Lapins (moderately resistant), and Van (susceptible). Water uptake as a percentage of fruit weight at cracking tended to be high in `Sue', medium in `Lapins', and low in `Van' and was related to the percentage of cherries remaining sound after 4 hours of immersion, suggesting that this trait is a factor in determining resistance. Mesocarp cells of `Sue' were more rectangular in section than those of the other cultivars. Skin elasticity and thickness of the cuticle did not explain resistance of `Sue' to cracking. Magnesium, copper, and phosphorus mineral contents were not related to cracking susceptibility, but the content of calcium, which influences cell wall integrity, in the epidermis of `Sue' was lower than in `Van'. Calcium content was not different in the hypodermal cells of the two cultivars. None of the anatomical features examined in this study explain the resistance to fruit cracking of `Sue'.