Dec. 3,1917 Temperatures of Cranberry Regions and Plant Growth 525 
The rate of growth of both fungi increases with rise of temperature up 
to at least 25 0 C., but their minimum temperatures are very different, 
Fusicoccum putrefaciens growing somewhat even at o° C., while the mini¬ 
mum temperature for the growth of Glomerella cingulata is apparently not 
far from 8° C. The results obtained with G. cingulata from cranberry agree 
fairly well with those obtained by Ames (1) for this fungus on bean agar, 
and by Brooks and Cooley (3) for the same organism on apple. Edger- 
ton (5) in his studies does not give minimum temperatures, but the maxi¬ 
mum for most of the strains of Glomerella used by him is well above 25 0 C. 
The temperature relations of a number of other fungi causing fruitrots 
of cranberries 1 has been determined by their growth on corn-meal-agar 
plates in an ice thermostat. While the temperatures of this apparatus 
were not absolutely constant and the results obtained are therefore not 
strictly comparable to those given in Table II, they furnish a satisfactory 
indication of the temperature relations of these fungi. 
Table; III .—Average growth {in centimeters) of fungi on corn-meal-agar plates for 15-day 
periods 
Approximate tem¬ 
perature. 
Guianardia. 
Acantho¬ 
rynchus. 
Phomopsis. 
Pestalozzia. 
Sporonema. 
Pythium sp. 
°c. . 
25. 
3-2 
5*2 
f W- °) 
<7 cm. in 7 
6.5+ 
f (22. 5) 
<9 cm. in 6 
20. 
2-3 
1. 0 
4*5 
[ days. 
9 + 
J 
3*7 
[ days. 
(17) 9 in 8 
15 . 
i. 6 
■ 5 
2. I 
7 
2* 5 
days. 
9 + 
IO. 
. 8 
0. 0 
. I 
2* 5 
i* 5 
5*5 
5 . 
0. 0 
0. 0 
O. O 
. 2 
. • 5 
.6 
1. 
0. 0 
0. 0 
0. 0 
0. 0 
0.0 
None of these rot-producing fungi grew at i° C.; Pestalozzia and 
Sporonema gave some growth at 5 0 ; and all except Acanthorynchus 
grew somewhat at io°. This last-named fungus, which has the highest 
minimum temperature of any cranberry fungus tested, has also the highest 
maximum, growing somewhat even at 34 0 C. 
TEMPERATURE INDEXES 
The temperature efficiency of the five localities was calculated sepa¬ 
rately for the two fungi, with the minimum temperature for growth on 
corn-meal agar as zero points—that is, 47 0 E. for Glomerella cingulata and 
32 0 for Fusicoccum putrefaciens . On this basis the remainder summa¬ 
tion indexes are as follows (Table IV). 
1 All fungi used in these temperature tests were isolated from rotten cranberries during the fall and winter 
of 1916 by Hr. Bert A. Rudolph, of the Bureau of Plant Industry. In many cases cultures of a species 
from several different localities were compared without finding any differences in temperature relations. 
