Apricot breeding for tolerance to Plum pox potyvirus in Nikita Botanical Gardens

Abstract

For the fi rst time, the results of studying of varieties and breeding forms of apricot in the gene pool collection of the Nikita Botanical Garden – the National Scientifi c Center of the Russian Academy of Sciences (NBS – NSC) (Yalta, Crimea) on the tolerance to the plum Sharka disease – Plum pox potyvirus (PPV), are presented in the article. The collection includes varieties from diff erent ecological and geographical groups that give us the possibility to present an objective comparative assessment of their susceptibility to phytopathogens. Based on long-term monitoring of the apricot orchards on PPV susceptibility in the collection of NBG-NSC, single aff ected plants were discovered and exterminated. Molecular genetic approaches to apricot breeding for tolerance were demonstrated and PPV tolerant genotypes were selected. According to the results of the research, hybridization was carried out. During the entire period of the research, in order to create genotypes tolerant to PPV, 28 738 fl owers were pollinated and 2 908 hybrid seeds were obtained from which plants were grown. Under in situ and in vitro conditions, new breeding forms tolerant to PPV were obtained. The prospect of biotechnological methods usage for inducing the development of hybrid apricot embryos was shown. The conditions for their culture (trophic, hormonal, and physical) were determined, viable seedlings and plants were obtained in vitro and planted for further adaptation ex vitro and to the open ground. New created plants were evaluated and breeding forms were selected, characterized by tolerance to PPV, good fruit quality and high stable yield. Based on the comprehensive studies, two breeding forms of apricot (‘97 -11 ’and ’97-17’) tolerant to PPV and promising for breeding and commercial cultivation were identifi ed.