CABBAGE YELLOWS AND THE RELATION Ob 
TEMPERATURE TO ITS OCCURRENCE 
JOSEPH C. GILMAN 
Formerly Rufus J. Lackland Fellow in the Henry Shaw School of Botany of 
‘ashington University 
[INTRODUCTION 
In recent years the diseases of plants caused by fungi be- 
longing to the genus Fusarium have assumed greater and 
greater importance from an economic standpoint. A large 
amount of work has been done on the descriptions of such dis- 
eases on new hosts, and on the taxonomy of the genus Fusa- 
rium, but there has been comparatively little study of the re- 
lations of these fungi to their hosts, especially of the condi- 
tions under which members of this genus may become harm- 
ful parasites. Therefore, any work which throws light on 
this point is of value scientifically, first, because the mode of 
attack and the other relations of the parasitic species of Fusa- 
rium are all very closely related and very similar in their 
nature, and second, because of the possibility of throwing light 
on the problem of immunity or resistance of plants to the at- 
tack of parasitic organisms. The latter point is of particular 
interest, since it will be recalled that, up to the present time, 
practically the only control of the diseases caused by fungi 
belonging to this genus, has been by the selection or develop- 
ment of strains of the host resistant to fungous attack. 
While assisting in the work of the development of strains 
of cabbage resistant to yellows in Wisconsin, investigations 
were undertaken to find the cause of the disease and the rela- 
tions between host and parasite. During these investigations 
the relation of temperature to the occurrence of this disease 
was found to be of utmost importance, and the principal part 
of the work was accordingly devoted to this side of the prob- 
lem. Nevertheless, before taking up these observations and 
experiments in detail, the results of the investigations into 
the etiology and pathological anatomy of the disease should 
ANN. Mo. Bor. Garb., Vor. 3, 1916 (25) 
