Variation in reaction to Phytophthora fragariae var. rubi in raspberry genotypes

In recent years Phytophthora root rot has become a major detriment to succe ssful raspberry (Rubus idaeus L.) production in various parts of the world. Until 1996 the British Columbia (BC) Agriculture and Agri-Food Canada (AAF C)- sponsored raspberry breeding program screened cultivars and selections for reactions to Phytophthora fragariae var rubi Wilcox & Duncan. Many of t he selections were early generation derivatives of the indigenous North Ame rican red raspberry, Rubus strigosus Michx. Selections of these derivatives , as well as several cultivars, showed as much resistance as the standard ' Latham'.