development of decay is the spore load carried by the fruit at the time 

 of packing. Washed, noninoculated apples developed fewer lenticel 

 and total infections than unwashed, inoculated ones and the latter- 

 fewer than those washed and inoculated. Where an adequate final 

 rinse of clean water was used, the addition of spores to the acid solu- 

 tion caused only slightly more decay than when uncontaminated 

 solutions were used. In both 1939 and 1940, immersing the fruit 

 in a suspension of spores before packing resulted in many times the 

 infections found in noninoculated fruit. 



The commercial significance of this test is that it emphasizes the 

 importance of a thorough final rinse of clean water in the control of 

 blue mold decay. Experiments (15) have shown that thousands of 

 fungus spores per cubic centimeter may accumulate in the washing 

 solutions and in rinse tanks in which the water is recirculated. If 

 these spores are not rinsed from the fruit prior to packing, much 

 decay may develop in the stored fruit. 



Packing Wet or Dry 



A number of investigators (9, 10, 11, 13, 14, 15) have studied the 

 effects of packing washed apples when wet or dry on the subsequent 

 development of decay; with few exceptions they concluded that 

 packing apples while wet did not cause an increase in decay. Heald, 

 Neller, and Overley (15) found that commercially sound and mechan- 

 ically injured fruit packed wet and held in common storage developed 

 more decay than comparable fruit packed dry. Robinson and Hart- 

 man (22, p. 31) reported that "fruit treated late in the season, after 

 more or less contamination had taken place, seemed to decay more 

 readily when packed wet." 



In 1938 part of the fruit was packed wet and part the day after 

 treatment, when the fruit was practically free of surface water. No 

 evidence was obtained (table 4) that blue mold decay was increased 

 by the fruit being packed wet. The apples packed wet presumably 

 became dry before the end of the minimum period necessary for the 

 germination of blue mold spores — 10 or more hours at 65° F. or room 

 temperature (1 , 8). 



Fruit Variability 



Records kept by commercial storage plants indicate that apples 

 from certain orchards consistently develop more blue mold decay, 

 particularly at lenticels, than those from other orchards. Baker and 

 Heald (2) obtained similar data and also found that apples from other 

 growers were severely decayed only in occasional years. They were 

 unable to correlate susceptibility to lenticel infection with irrigation 

 (2), fertilizer practice (2, 3), or fruit size (2), but they found that 

 advanced maturitv at harvest definitely predisposed the fruit to 

 infection (2, 3). 



In the present study it was found that fruit from the different or- 

 chards varied in susceptibility (table 6), the differences apparently 

 being due both to seasonal factors and to conditions existing in some 

 of the orchards. In 1939, apples from the Wiley Heights orchard 

 developed more than twice as many lenticel infections as those from 

 any other orchard, whereas in 1940 they developed the fewest infec- 

 tions. The data in table 1 show that the fruit from this orchard did 



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