that apples held in cold storage for 6 to 10 weeks before they were washed had 
developed a resistance to washing injury and decay. 
In 1948 English (51) reported that the use of sodium chloro-orthophenyl- 
phenate (Dowicide-C) used in a rinse or in an alkali wash reduced blue mold and 
gray mold rot by 80 to 95 percent on wounded, inoculated apples. Bull's-eye 
rot, however, was not reduced. 
Elaborating on decay control in the Northwest, English and others (53) 
recommended the addition of Dowicide-C to the sodium silicate washing solution. 
With this method, Dowicide-C at 1.2 percent concentration, followed by a fresh 
water rinse, did not cause injury and reduced blue mold and gray mold rot 18 to 
20 percent. If used as a final rinse at 0.4 percent, Dowicide-C reduced total 
rot 43 to 75 percent. They mentioned the incompatibility of the chemical with 
acid and warned that Dowicide-C was irritating to workers and could cause a form 
of dermatitis. 
Wright and Smith (182) studied the relation of bruising and maturity of 
Delicious apples to blue mold rot. They found that mature apples were much more 
susceptible to the blue mold rot fungus than immature fruits when bruised and 
inoculated. Fruits inoculated immediately after bruising were much more sus- 
ceptible to infection and decay than similarly treated fruits that were bruised 
but stored for several weeks before inoculation. They also showed that bruised, 
inoculated fruits that were cooled slowly and were stored at 35° F. developed 
appreciably more decay than quick-cooled fruits stored at 32°. (See also sec- 
tion on Bruise Control.) 
In 1962, Eckert, Kalbezen, and Sleesher (47) reported that an aqueous 
solution of 0.5 percent 2-aminobutane salt provided better control of peni- 
cillium rot on apples dipped for 1 minute than a comparable solution of sodium 
o-phenylphenate. 
Apples are sensitive to certain chemicals and may be directly injured or 
have the flavor impaired. (See Chemical Injury, p. 166.) 
Beraha and others (18, 19) reported that if Jonathan apples were inocu- 
lated with Penicillium expansum Thom and incubated 24 or 96 hours prior to 
irradiation that a minimal gamma ray dosage of 100,000 rep (roentgen equivalent 
physical) was required to arrest the progress of decay when held for 6 days at 
70° to 95° F. Inoculated apples held 10 days before irradiation required 
200,000 rep to arrest decay. Neither dosage caused visible injury to the 
apples. 
Bull's Eye Rot (Neofabraea malicorticis Jacks. and N. perennans Kienh.) 
In this review the term bull's-eye rot of apples refers to the decay 
caused by two closely related fungi Neofabraea malicorticis and N. perennans, 
In addition to the fruit rot, the fungi cause serious cankers on apple trees 
in certain localities. 
These fungi have been reported as causing disease in California, Illinois 
Idaho, Maine, Massachusetts, Oklahoma, Montana, Washington, and Oregon. The 
disease is of economic importance, however, only in the Northwest. 
Tree cankers are the source of spores for fruit contamination or infec- 
tion which may later develop into bull's-eye rot. 
Kienholz (82) lists three conditions necessary for infections of sus- 
ceptible apple varieties: (1) adequate source of spores in tree cankers; (2) 
sufficient rainfall to wash the spores over the fruits; and (3) rainfall per- 
sisting long enough for spores to germinate and cause incipient infection. 
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