ON THE CRACKING OF SWEET CHERRIES

Data from several years and 1,179 plants of 48 progenies in the Ahrensburg sweet cherry breeding program were analyzed for genotype cracking response in relation to rainfall from 6 days preharvest through harvest, together with their respective parents. As could be expected, the correlation over 26 parental cultivars with 254 pairs of data (several trees and years) was low, r = 0.31***. The correlation coefficient over all 2,380 pairs of progeny data was lower still, r = 0.27***. About half of the progenies had significant positive correlations, varying from r = 0.84*** to 0.20*. Among the non-significant progenies, there were even two negative correlations. There was no clear relation between the cracking incidence of the parents and the resulting progenies. The progenies generally had higher values than their respective parents with few exceptions. As expected, ‘Van’ is among the cultivars with the highest cracking percentages as both a parent and as a cultivar, with 32 and 28%, respectively.