CONTENTS 



Page. 



Introduction 9 



Historical account of the bitter rot 11 



Distribution of the bitter-rot fungus 12 



Geographical distribution 12 



Occurrence on various hosts 14 



General description of the bitter rot 15 



Time of appearance 15 



Character of the spots 16 



Cause of the bitter rot 17 



Rate of development of the bitter rot 18 



The diseased apple 19 



The bitter-rot fungus 19 



Life history on apples 19 



The conidia 21 



Growth in cultures — conidial and ascus stages 22 



The name of the bitter-rot fungus 25 



The canker stage 29 



Discovery of the canker 29 



Description of the canker stage 31 



Relation of the cankers to the bitter rot 32 



Spread of the bitter rot 36 



Remedial measures 38 



Removal of diseased fruits and mummies 38 



Removal of limb cankers 39 



Spraying with fungicides 40 



Summary and recommendations 44 



Index to literature 46 



Description of plates 53 



7 



