INFLUENCE OF SOIL TEMPERATURE AND SOIL MOIS¬ 
TURE UPON THE FUSARIUM DISEASE IN CABBAGE 
SEEDLINGS ^ 
By W11.WAM B. Tisdale * 
Formerly Instructor in Plant Pathology, Wisconsin Agricultural Experiment Station 
INTRODUCTION 
The pioneer investigations concerning the influence of soil temperature 
upon cabbage yellows caused by Fusarium conglutinans Wollenw. were 
conducted in Wisconsin by Gilman {8),^ His experiments were con¬ 
ducted in greenhouse rooms with rather wide fluctuations of air tempera¬ 
ture, where the soil temperature could not be held constant for any great 
length of time. Consequently, Gilman did not determine the complete 
range of soil temperature for the occurrence of the disease, nor did he 
inquire into the possible influence of soil moisture. 
Since the publication of Gilman’s paper, plant pathologists have con¬ 
tinued to make observations on the influences of air and soil tempera¬ 
tures upon the growth of the plants and upon the occurrence of yellows 
in the Wisconsin cabbage fields. During the midsummer months when 
the soil is dry and hot, cabbage plants begin to languish and assume a 
pale, lifeless color.. Growth is markedly checked, especially when these 
conditions obtain for two or three consecutive weeks. It is during this 
trying period that yellows develops in its most destructive form on the 
“cabbage sick”^ soils. During very dry hot seasons even the resistant 
strains of cabbage, such as the Wisconsin Hollander, may show a consid¬ 
erable percentage of incipient disease, but upon the return of more favor¬ 
able weather conditions (rain and lower temperature) they usually over¬ 
come the attack and produce marketable heads. Such field observations 
soon convince one that the occurrence and severity of yellows are closely 
correlated with the influences of soil temperature and soil moisture, and 
the presumption would seem to be that these influences relate both to host 
and to parasite. 
The writer undertook to learn more exactly the importance of these 
factors as they affect young seedlings, beginning the work in the summer 
of 1917. The purposes outlined were: (i) To determine the range of soil 
temperature for the occurrence of yellows in cabbage seedlings; (2) to 
study the influence of such soil temperatures upon the normal growth of 
cabbage seedlings in noninfested soil; (3) to study the influence of high 
soil temperature upon the relative susceptibility shown by the resistant 
strain, that is, upon the possible “breaking down” of resistance; (4) to 
determine in a like manner the influence of soil moisture both upon the 
growth of cabbage plants and upon the occurrence of yellows in them. 
1 Accepted for publicaticm Jan. s, 1922. 
* The writer wishes to make grateful adcnowledgment to Prof. r. R. Jones, of the University of Wiscon¬ 
sin, for supervision and helpful suggestions during the progress of this work. 
* Reference is made by number (italic) to “Literature cited,” p. 86-86. 
< The term “sick” or “cabbage sick” soil as used in this paper indicates soil infested with Fusarium con¬ 
glutinans. 
Journal of Agricultural Research, 
Washington, D. C. 
adb 
(55) 
Vol. XXIV. No. I 
Apr. 7, 1923. 
Key No. Wis-.2o 
