Voor de practische kweker bruikbare methoden van resistentie-onderzoek

Summary In breeding new varieties it will be necessary in most cases to test the degree of resistance of the material by means of artificial infection. After discussing with plant breeders and phytopathologists the question of the research on disease resistance now being done in the Netherlands the Department of Research on Disease Resistance of the Institute for Phytopathological Research at Wageningen have found that the methods mentioned in addendum I are reliable enough to be used by the breeders themselves, though with the aid of the Department.The methods applied in special institutes because they are too complicated for the breeders, are mentioned in addendum II; they are wart-disease testing in potatoes, virus testing in strawberries and raspberries.Under III are treated the methods that are as yet not sufliciently developed to be applied successfully either by institutes or by breeders, and which are now being investigated in the Netherlands.