over the years. Based upon the storage conditions to which these varieties 
were best suited, they classified them into 3 groups: (1) Those which respond 
best in an atmosphere where the CO, and 05 levels total 21 percent, (2) those 
which respond best in an atmosphere where the CO, and 0, levels total less than 
21 percent, and (3) those which will not tolerate CO, and should be stored in 
air. They placed Bramley's Seeding in the first group, suggesting an atmos- 
phere of 9 percent CO, and 12 percent 0, at 40° F. Cox's Orange Pippin was 
placed in the second group as it Lespanded more favorably in an atmosphere of 
5 percent CO» and 2.5 percent 0, at 34°. Newton Wonder and Blenheim Orange 
were two varieties for which they recommended air storage. West (103) further 
pointed out that CO» levels of 13 percent or more were liable to injure the 
fruit. This injury was referred to as brown heart but now is generally called 
COy injury. To reduce the likelihood of scald injury in gas storage they sug- 
gested the use of scald control measures, such as oil wraps, on those varieties 
susceptible to this disorder. 
Canada 
Reports on CA storage in Canada indicate that McIntosh may be stored 
from 34° to 40° F. in atmospheres of 5 percent CO, and 2.5 to 3 percent 0» or 
7 percent CO, and 14 percent 09 (72, 79, 21, 29). ‘Core flush (brown core), 
which develops in McIntosh stored at 30° to 32° F., is controlled by the higher 
storage temperatures. CA storage at these higher temperatures more than com- 
pensates for the shortened storage life that would otherwise occur at the high- 
er temperatures, Eaves (21) and Phillips and Poapst (77) found the 7 percent 
CO, and 14 percent O, mixture as good as or better than the 5 percent CO, and 
3 percent 0) mixture for McIntosh particularly where scald is not a problem 
(77). However, Phillips and Poapst (75) found the occurrence of scald to be 
more likely in the 7 percent CO, and 14 percent 0, atmosphere than in the lower 
CO,-05 mixture. On Cortland, Pot ltins and Poapst (74) found different 0) levels 
had no effect on scald. The best control of scald on Cortland in CA storage 
was obtained with DPA (Diphenylamine) dips (73). 
In one study Phillips and Poapst (76) observed an unusual number -of 
sprouted seeds in a lot of McIntosh that also had core flush. In an experiment 
to test the effect of CA storage conditions on seed germination, they found 
that conditions which most effectively reduced core flush also had the greatest 
inhibitory effect on seed germination. They suggested that this information 
may be of use to determine whether a given lot of fruit had or had not been 
stored under CA conditions. 
Australia 
In their studies on Australian apples, Huelin and Tindale (38) found 
three of eight varieties tested responded favorably to CA storage. They recom= 
mended an atmosphere of 5 percent CO, and 1€ percent 0, for Jonathan, Democrat, 
and Granny Smith. They suggested a storage temperature of 31° to 32° F. for 
the last two varieties but for Jonathan they suggested 36° the first month, 34° 
the second month, and 32° for the rest of the storage period. These conditions 
controlled Jonathan spot and soft scald, but some breakdown and brown heart did 
occur in the Jonathans. Scald was controlled on Jonathans by oil wraps but even 
these did not always provide control of scald on Granny Smith. Hail (35) found 
86 
