Breeding potatoes with two or more resistance genes from closely related species, combined with introduced resistance management, offers growers the greatest promise of withstanding late blight (Phytophthora infestans) at lower volumes of chemical control, according to an international conference held at Wageningen earlier this month to mark the conclusion of the Dutch Government-funded Durable Resistance against Phytophthora (DuRPh) project. “Such a genetically plastic pathogen can break through the defences of resistant plants relatively easily,” said Wageningen UR representative Erik Toussaint. “Combining sets of multiple resistance genes from related species, introduced into the crop via, for instance, genetic engineering, together with proper monitoring of the pathogen and timely application of combined resistance genes, will allow cultivars to retain their resistance in the long term.” This is also likely to hold true for other crop pathogens, he added. Source: Horticulture Week