CONTENTS. 



Page. 



Introduction 9 



Potato culture in Europe 9 



Observations on potato diseases and disease resistance in Europe 12 



Certain minor diseases 12 



Internal brown spot 12 



Filosite, or growing-out 13 



Leaf-spot 13 



Scabbiness of tubers 14 



Potato scab 14 



Varietal resistance to scab 15 



Other scab-like diseases 16 



Potato stem diseases 17 



Blackleg 17 



Other stem diseases 18 



Late-blight and rot due to Phytophthora infestans 19 



Resistance as shown toward late-blight and rot 20 



Historical statement 20 



The meaning of disease resistance 23 



Disease resistance and vegetative vigor 23 



The relation of hybridity to disease resistance 25 



Improvement by selection 25 



Are early or late varieties the more resistant? 26 



Relation of source of seed and cultural methods to disease resistance 26 



Composition and character of tubers as related to rot resistance 27 



Character of stem and foliage as related to disease resistance 28 



Disease-resistant varieties of Europe 28 



Great Britain 29 



Germany and Holland 30 



France and Belgium 30 



Disease-resistant varieties of America 31 



Investigations at the experiment stations 31 



Work at the Vermont station 32 



Information secured by a circular of inquiry 33 



Resistance to scab 35 



Summary 37 



7 



