ROTS OF EARLY STRAWBERRIES IN FLORIDA AND 
SOUTHERN CALIFORNIA 
Neil E. Stevens 
(Received for publication July i8, 192 1) 
The fungi causing rots of strawberries in the southern states have been 
under investigation since 191 5. Each season Florida strawberries have been 
examined either in the field or in the market by one or more of thovse in- 
terested in the investigation. During several seasons shipping tests were 
carried on, and the same fruit was examined both before and after ship- 
ment. Although there have been found on Florida strawberries fungi be- 
longing to numerous genera, Rhizoptis nigricans Ehrb. has remained the 
commonest and most destructive of the fungi causing decay of ripe straw- 
berries from this region. 
Four months' study, January to May 15, 1920, of southern California 
strawberries both in the field and in the market showed a condition quite 
different from that in Florida. R. nigricans appeared to be of distinctly 
minor importance as a cause of fruit rot of strawberries; whereas a large 
proportion, frequently over ninety percent, of the rotten berries examined 
during the four months were affected with a species of Botrytis, probably 
Botrytis cinerea Pers. 
There is, then, apparently a marked difference in the relative abundance 
of these fungi on early strawberries in the two regions, and the probable 
reasons for this difference are discussed in the present paper. No one 
would, of course, presume to generalize from the observations of a single 
season, but so competent and experienced an observer as Dr. H. S. Fawcett 
of the Citrus Experiment Station at Riverside, California, assures the 
writer that the extreme prevalence of Botrytis on strawberries is a regular 
phenomenon of the winter season in southern California. 
The regions under consideration include the most southerly important 
strawberry shipping points on the Atlantic and Pacific seaboards. The 
strawberry-growing region of central Florida lies east of Tampa, Plant City 
and Lakeland being the chief shipping points. The southern California 
strawberry area lies chiefly in Los Angeles county, Gardena and Moneta 
being large shipping points. Attention will be confined to the early shipping 
season, during a portion of which these two regions usually dominate their 
respective markets. 
The Fungi 
In using the specific names Rhizopus nigricans and Botrytis cinerea, the 
writer does not intend to enter upon the debated ground as to whether the 
fungi so designated constitute good species or collections of species. It is 
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