A BUDROT OF THE PEACH CAUSED BY A SPECIES OF 
FUSARIUM 1 
By John W. Roberts 
Pathologist, Fruit-Disease Investigations > Bureau of Plant Industry, United States 
Department of Agriculture 
In July 1920, peach twigs having numerous dead and blackened buds 
were sent me from Georgia by Leslie Pierce, of the Office of Fruit Disease 
Investigations, Bureau of Plant Industry. It was stated that the tree 
from which the collections were made was a fairly well grown specimen 
of the variety “Queen of Dixie” peach and that dead buds were present 
ip considerable numbers. The injury was not entirely confined to the 
buds, there being also a slight discoloration of the twig near the axils. 
Judging from the size and state of development of the buds, death 
occurred early in the spring, at a time when they had just begun to swell. 
At first it was thought that Monilia might be responsible for the injury, 
but no conidia of Monilia could be found on the buds as received or after 
keeping them in a moist chamber for 48 hours. However, conidia of a 
species of Fusarium were found to be present under both conditions. 
After the 48 hours in a moist chamber, they were particularly abundant, 
being produced in white sporodochia, dotting the surfaces of the bud scales. 
The same fungus was found in diseased buds of the variety “Queen of 
Dixie” peach, also sent in from Georgia during the early spring of 1922 
by John C. Dunegan of the Office of Fruit Disease Investigations, Bureau 
of Plant Industry. 
Aderhold 2 described a budrot of the sour cherry which he showed was 
caused by Fusarium gemmiperda sp. n. Buds killed by this disease did 
not remain on the trees throughout the summer, as is usually the case 
when attacked by Monilia, but by the development of an abscission layer 
were made to fall early in the season. No injury to the trees themselves 
was observed by Aderhold, but the crop of fruit was much reduced. 
The principal points in Aderhold’s description of the fungus are as fol¬ 
lows: Dead buds placed in moist chambers developed snow-white sporo¬ 
dochia in five to six days. The conidia were at first nonseptate, most of 
them later becoming triseptate, somewhat curved, at first barrel-shaped 
or cylindrical, later sickle-shaped, pointed at both ends, contents hyaline 
or somewhat granular, later a large vacuole in each cell. They were vari¬ 
able in size, according to age, usually being between 35-45 x 4-5.5 
microns. Individually the conidia were colorless, but with age they 
took on a reddish color in mass, especially beautiful in artificial culture. 
The conidiophores were either long or short and arose from neighboring 
branches in large numbers. There were no “ Kopfchen” which are often 
found on aerial conidiophores of species of Fusarium, and no chlamydo- 
spores. Mycelial concretions, consisting of cartilaginous dirty white or 
yellowish masses of hyphae, were present. They were thought to be the 
beginnings of sclerotia, but no further development took place. Even 
1 Accepted for publication Nov. i, 1923. 
2 Aderhold, Rudolf, ein der moniliakrankheit ahnlicher krankheitspall an einem sauer- 
kirschbaume. In Zeitschr. Pflanzenkrank., Bd. 11, p. 65-73, pi- 2. 1901. 
( 507 ) 
Journal of Agricultural Research, 
Washington, D. C. 
aif 
Vol. XXVI, No. xo 
Dec. 8, 1923 
Key No. G-343 
