10 BULLETIN $*6. U. S. DEPARTMENT OF AGRICULTURE. 
which has been attributed to Botrytis (7, p. 950) is apparently largely 
due to its frequent occurrence in strawberry fields under certain cir- 
cumstances and to its ability to produce aerial hyphae at relatively low 
temperatures. Under the conditions found in many refrigerator 
cars, strawberries affected with Botrvtis often develop abundant 
fine, gray, sterile aerial hyphae, often 2 cm. or more in length. A few 
such berries on the top of a crate attract immediate attention and give 
the impression of general decay. On removal from the cool, moist 
air of the refrigerator car these aerial hyphae collapse and are replaced 
by much shorter (2 to 3 mm.) fertile hyphae, which produce mature 
spores in a short time, often within 36 hours. 
The ability of Botrvtis to grow at low temperatures has been 
frequently noted. Brooks and Cooley (2, pp. 156 and 159, fig. 15) 
found that it would grow somewhat at 0° C. on corn-meal agar in 
Petri dishes and would even germinate at this temperature, while 
Fulton in the course of storage experiments on small fruits found that 
this fungus (3, p. 19) ''grows luxuriantly in warm temperatures and 
slowly in the coldest temperatures in which the fruit can be stored 
safely without freezing." (See also 3. pi. 1, D. and pi. 3.) 
The fact that berries destroyed by Botrvtis are frequently brownish 
when they arrive at then destination has caused some inspectors to 
apply the term ''brown-rot" to this disease. This name is, however, 
unfortunate, since it is now customarily limited in application to a 
different class of diseases. 
In striking contrast to strawberries rotted by Rhizopus. those 
affected by Botrytis are even firmer than normal berries, retaining 
then shape even after abundant spores are produced and finally 
becoming hard and dry. For this reason, therefore, and because 
Botrytis is a field trouble rather than a rot of berries in shipment, it 
seems that the descriptive term "dry-rot," already in use among 
growers in some sections, might well be applied to this disease. 
RELATION OF BOTRYTIS TO INFECTION BY RHIZOPUS. 
In his first paper dealing with decay of strawberries in transit, 
F. L. Stevens regarded Botrytis as a primary cause of decay in transit 
and stated that "Botrytis initiates the decay, opening the way to 
such other saprophytes as may be present. Of such saprophytes 
Rhizopus is by far the most prominent and most abundant.*' On the 
basis of a histological study of strawberries infected with these two 
fungi, one of the writers stated in 1916 that Rhizopus ordinarily 
entered strawberries through wounds and was "not dependent on 
the presence of any other fungus in its attack on strawberries during 
shipment and on the market" (10, p. 366"). It was, of course, recog- 
nized at this time that these observations did ''not preclude the 
possibility of Bltizopus sp. following in an area originally infected by 
