12 BULETIX 686, U. S. DEPARTMENT OF AGRICULTURE. 
secured when Rhizopus was inoculated into an area already infected 
by Botrytis. 
During the experimental shipment between Monett, Mo., and 
St. Paul, Minn., some berries attacked by Botrytis were kept in a 
warm car, some were exposed to the air, and others were surrounded 
by leaky berries on which RMzopus nigricans was fruiting. While a 
few of the diseased berries became infected with Rhizopus, the per- 
centage of such infections was smaller than in the case of uninfected 
berries kept under similar conditions as checks. Most of the berries 
infected with Botrytis, on the contrary, became brown in color, 
firm in texture, and retained their shape for a week or more except 
for some slight shriveling. 
At Hammond, La., on April 25, 1917, boxes of apparently sound 
berries and also of berries infected with Botrytis were selected. 
These were held at room temperature, without refrigeration, for 48 
hours and then examined. Of the berries which had been apparently 
sound, 79 per cent were now typical leaks and 9 per cent showed soft 
spots due to Rhizopus infection. The berries which had shown 
lesions of Botrytis, on the other hand, now contained only 19 per 
cent of leaky berries and 9 per cent which showed small Rhizopus 
infections. In no cases were the latter apparently associated with 
the Botrytis infections. This seemed to indicate that the presence 
of Botrytis inside the berry actually inhibited to some extent the 
growth of Rhizopus. 
It is, of course, not impossible that Rhizopus may follow in a region 
infected by Botrytis. Since, however, the writers have not been 
able to find a case of this sort or to produce it artificially, it may 
perhaps be fairly assumed that this type of infection is relatively 
rare. 
SUMMARY. 
Leak, caused by RMzopus nigricans, is by far the most important 
rot of strawberries after picking. 
Losses from leak can be most effectively reduced by keeping berries 
at low temperatures and by handling them carefully. 
Berries picked in the early morning are cool and less likely to 
decay than those picked during the heat of the day. 
Adequate refrigeration greatly reduces the rate of growth of 
RMzopus nigricans in transit. 
Washing strawberries to remove dirt may have a beneficial effect 
if the berries are washed in clean water, handled with care, packed 
in the crates while still wet, and refrigeration is not too long delayed. 
Less bruising results if the berries are packed in boxes and then washed 
by dipping the entire box or by running water through it than if 
the berries are washed before packing and plating. 
