Vol. 49 3 a No. II 
BULLETIN 
OF THE 
TORREY BOTANICAL CLUB 
NOVEMBER, 1922 
Effect of external and internal factors on the germination 
| fungous spores 
Ws. L. Doran 
(WITH TWO TEXT FIGURES) 
The greater part of the work ‘which has been done on the 
germination of fungous spores has been incidental to studies of 
the life histories of fungi. References to spore germination are 
in. most cases isolated and few attempts have been made: to 
draw any general conclusions from the results obtained. Since 
all fungous diseases must begin with infection and since the 
germination of the spore is the forerunner of infection, further 
knowledge of the conditions which favor or inhibit spore germina- 
tion is of great practical importance. In this paper are des- 
cribed the results of the writer’s study of the effect of various 
factors on the germination of fungous spores. 
It is becoming increasingly common for field studies of the 
efficiency of fungicides to be preceded by laboratory tests of 
the toxicity of fungicides to fungi. If fungous spores are to be 
germinated both in the presence and absence of fungicides, it 
is important that all other conditions be identical and at or near 
the optimum. It is therefore necessary that optimum conditions 
for the germination of the spores be known before the laboratory 
tests of fungicides are made. 
Frequent references are made in the literature to the effect of 
prevailing climatic conditions on the outbreak or severity of 
Reine aa ee —The author gratefully acknowledges the assistance 
and encouragement received from Dr. O. R. Butler in this wor 
[The aa sgh October (49: 283~312. pl. 12-17) was seittand October 
11, 1922.] 
313 
