Fisher and Porritt (21) in 1951 reported that the overapplication of nitrogen 
may impair the keeping quality of apples in British Columbia. Blasberg (7) 
found fruit from McIntosh trees given foliar sprays of urea to be softer than 
fruit from trees receiving a soil application of nitrogen. Smock and Neubert 
(48) and Weeks, et al. (69) also point out that too much nitrogen may result 
in soft fruit or fruit that is poor in keeping quality. Southwick (56) found 
indications that 2, 4, 5-trichlorophenoxypropionic acid would speed up the rate 
of softening of apples from high nitrogen trees sooner and to a greater degree 
than it would fruit from trees at lower levels of nitrogen. However, he pointed 
out that trees having the high nitrogen level also had lower potassium and mag- 
nesium levels and therefore one could not assume the effects to be entirely due 
to the higher nitrogen level. A nitrogen level in the foliage above 2.0 to 
2.1% has been reported to reduce the quality of McIntosh and Northern Spy apples 
(17, 32, 47). Hill, et al. (32) found a negative correlation between the level 
of nitrogen in the foliage and the quality score of the fruit. Eggert, et al. 
(20), however, found a taste panel preferred McIntosh apples from trees having 
a high foliage nitrogen to those from trees with a low foliage nitrogen. The 
data of Eggert, et al., did agree with that of Hill and his co-workers, in that 
the softest fruit at harvest came from trees with the high nitrogen level, but 
after 3 months' storage this difference in firmness disappeared. Jonathan 
apples, too, were found to be softer when they came from trees whose foliage 
nitrogen was high than firmer fruit from low nitrogen trees (10). Ostrowska 
and his associates (44) found that Antonovka apples from trees fertilized with 
NP were firmer both at harvest and after storage than fruit from trees ferti- 
lized with CaNPK, A report of studies in New Zealand (63) stated that nitrogen 
reduced the storage quality of Sturmer, Cox's Orange Pippin, and Jonathan apples 
but had little effect upon Dunn or Delicious, Similar results were obtained on 
Cox's Pippin by Montgomery, et al. (42). Fruit from trees with a high N/K 
ratio has been found by some to indicate poor storage quality (32, 47). Con- 
trary to these reports. Padfield (46) reported combined NPK fertilizers in- 
creased yields with no significant deterioration in keeping quality of the 
fruit, provided the quantity of N fertilizer was restricted to 2 pounds per 
tree, 
Tiller and his co-workers (63) reported that the addition of P or PK to 
N fertilizers improved quality, though their best quality fruit generally came 
from unmanured trees. In general, P has been found to exert little if any 
marked influence on the storage behavior of apples (10, 32, 47). BUneman et al, 
(10) one year found low levels of potassium were associated with an increase of 
internal breakdown in Jonathans, Hill, et al. (32) reported a positive trend 
between potassium levels of the foliage and the quality score of the fruit. 
Wallace (68) also reported instances of a flesh breakdown in fruit from trees 
deficient in potassium, but he also observed such breakdown to occur in fruit 
from high potassium areas, Barden and Thompson (1) found that even heavy potas- 
sium treatments had no effect on fruit color or storage life of Red Delicious 
apples. 
The effects of boron on storage quality are also complex. Haller and 
Batjer (25) reported a number of varied effects resulting from the use of boron 
fertilizers. They found that borax applications did not consistently affect 
firmness, reduce scald in some varieties, or increase internal breakdown in 
Jonathans. Bramlage and Thompson (8) also found boron sprays increased the 
occurrence of internal breakdown of Jonathans. They further reported that mul- 
tiple sprays of boron applied early in the season significantly reduced the 
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