RHIZOPUS EOT OF STRAWBERRIES IN TRANSIT. H 
arrival in good order. Some of the remainder was held in the car two or three 
days and part of it at a commission house, and it deteriorated very rapidly, 
owing to the attacks of Rhizopus nigricans. The fruit leaked badly, many. of 
the peaches becoming completely penetrated and overgrown by the rot fungus. 
In this case the fungus appeared to grow readily from one fruit to another, 
possibly through the stem end. 
It is significant that in all cases where the rot caused by Rhizopus 
nigricans is described it is characterized by the loss of a large quan- 
tity of liquid from the deca}^ed tissue. Behrens (2) and Wormald 
(IT) speak of this in discussing the rot of tomatoes, Halsted (7) in 
quince, Orton (11) in potatoes, and Waite in pears and peaches. 
The observations recorded above show that Rhizopus is the chief 
and in some sections practically the only cause of rot of straw- 
berries in transit. They show that the percentage of moisture in the 
air makes no difference in the rate of growth of the fungus inside the 
berry. Also, that while the growth of Rhizopus is very slow at 10° 
C. (50° F.) or below, the rate increases rapidly with the rise of tem- 
perature above that point, so that at favorable temperatures a straw- 
berry infected with Rhizopus is destroyed in a few hours. Micro- 
scopic studies by one of the writers (13), as well as inoculation 
experiments and field observations, indicate that Rhizopus does not 
usually penetrate the uninjured epidermis of the strawberry. 
From this work it is apparent that no method of drying the air of 
the container in which the strawberries are shipped, by ventilation 
or otherwise, will retard the decay of the fruit once the fungus has 
entered, but that rot of strawberries in transit may be diminished 
greatly by reducing the amount of infection by Rhizopus or hj keep- 
ing the berries at a low temperature from the time they are picked 
until sold. The importance of low temperature in shipping straw- 
berries was demonstrated by Parker Earle during the period from 
1866 to 1872 (3 and 4). Earle found that strawberries cooled to 
50° F. in a specially constructed cooling house previous to shipment 
might be sent long distances in refrigerator cars in practically perfect 
condition. 
PRESENT SHIPPING PRACTICES.* 
To appreciate the general lack of complete refrigeration and the 
importance of reducing infection by Rhizopus, it is necessary to 
know something of the methods of handling strawberries now in 
general use. 
1 Descriptions of the development of refrigerator transportation of truck produce were 
published in 1901 by F. S. Earle (3) and W. A. Taylor (15). Of particular interest in 
this connection are the descriptions (3, p. 444; 15, p. 575) of the early work of Parker 
Earle in shipping strawberries under refrigeration. So far as the writers have been able 
to learn, Parker Earle designed the first refrigerator chest for shipping strawberries by 
express and was the first to demonstrate the effectiveness of precooling. His letter 
(3, p. 444-445) places the beginning of this work about 1866, and it was mentioned by 
Holcomb in 1870 (10). 
