CONTENTS 



PAGE 



The disease 3 



Names, history, and geographical range 3 



Economic importance 4 



Symptoms 5 



Etiology ■ 6 



Nomenclature, and review of literature 6 



Morphology and physiology 6 



The mycelium 6 



The sclerotial cells 7 



The fruiting stage 8 



The temperature range for growth 8 



The pH range for growth 9 



The production of sclerotia in culture 11 



Pathogenicity 14 



Historical aspects 14 



Experimental data 14 



Inoculation experiments 16 



Susceptibility of different varieties of Brassica oleracea L 16 



Susceptibility of other species of plants 16 



Susceptibility of plants of different ages 16 



Biologic specialization 17 



Review of literature 17 



Experimental data - 19 



Longevity of the fungus in the soil 25 



Temperature and moisture studies 26 



Experimental methods and data 26 



Temperature-moisture relations 26 



Bottom as compared with top watering 52 



Effect of surface layer of sand 55 



Control 58 



Summary 58 



Bibliography 59 



