Divergence and selection of peach trees and nectarine trees based on cold damage of its fruit

Resumo

The knowledge of the post-harvest physiology of the fruit is of great importance in order to have technical subsidies aimed at extending the storage time without, however, altering its physical, organoleptic and nutritional characteristics, and, especially, in the case of the peach, due to its fragility. The objective was to evaluate the genetic divergence among 40 peach trees and nectarine trees genotypes based on the susceptibility fruit to cold damage. The study was carried out at EEAD-CSIC, Zaragoza - Spain. The susceptibility to cold damage was assessed after 14 and 28 days of cold storage using temperatures of 0º and 5ºC for symptoms of the presence of physiological disorders as wooliness mealy, grainy, leathery, changes in the color of the mesocarp, browning, bleeding and absence of flavor. As a selection criterion, 20% of the genotypes with the highest frequency of superiority were adopted in terms of quality characteristics, that is, the least damage presented. Divergent groups were formed, demonstrating that the accessions showed different behaviors among the tests. The ‘Queen Giant’ access showed less susceptibility to damage and differed genetically, according to the applied methods. In this way, it can be introduced as a genitor in breeding programs.