and in lenticels injured by the washing process, emphasizes the im- 

 portance of careful handling and mild washing in the control of blue 

 mold decay. 



Table 3. — Infection courts for blue mold in washed and unwashed Delicious apples 



[Fruit harvested Oct. 2, 1939, or Sept. 25, 1940, washed in sodium silicate (80 pounds to 100 gallons) and then 

 in 1.5-percent hydrochloric acid, dipped in a suspension of blue mold spores, packed, and stored at 32° 

 until Jan. 15. In each treatment composite 50-apple samples from each of 5 orchards were used. All 

 temperatures in ° F.] 



Type of washing 



Fruits 

 showing 

 washing 



injury 



Fruits 

 decayed 



Infections per 50 fruits 



Lenticel 



Stem 

 and 

 calvx 



Mechan- 

 ical 

 injury 



Visible 



washing Total 

 injury 



Unwashed 



Silicate (100°)+acid (80°). 

 Silicate (110°)+acid (100°) 



Acid (80°) 



Silicate (80°) 



Acid (105°) 



Silicate (105°) 



1940 

 Unwashed 



Silicate (100°)+acid (80°). 



Acid (80°) 



Silicate (80°) 



Percent 



0.0 



25.2 



76.8 



.0 



.0 



30.8 



8.4 



.0 



20.0 



.0 



.0 



Percent 



7.2 



21.6 



30.8 



24.4 



4.0 



14. P. 



7.2 



11.2 

 21.6 

 17.8 

 11.4 



Number 

 1.8 

 8.2 

 13.0 

 9.8 

 1.2 

 4.0 

 2.8 



1.4 

 10.2 

 5.8 

 4.4 



Number 

 0.4 

 .2 

 .4 

 .2 

 .0 

 .2 

 .4 



.2 

 1.0 

 .2 

 .2 



Number 

 2.2 

 4.0 

 3.2 

 4.0 

 1.0 

 3.2 



4.2 

 2.4 

 4.2 

 2.6 



Number 



0.0 



1.8 



9.8 



.0 



.0 



1.0 



.2 



Number 

 4.4 

 14.2 

 26.4 

 14.0 

 2.2 

 8.4 

 4.2 



.0 



5.8 



.0 



14.6 



.0 



10.2 



.0 



7.2 



Holding Fruit in Orchard or Warehouse 

 Prior to Washing 



An increased awareness among shippers of the necessity for better 

 fruit quality and the provision of larger cold-storage facilities in the 

 production areas have resulted in a tendency to remove apples from 

 the orchard to cold storage with less delay than was the case some 

 years ago. That prompt storage of the fruit at low temperatures 

 would result in less decay than delayed storage seemed evident from 

 the early work of Ramsey, McKay, Markell, and Bird (21) ; also 

 Plagge, Maney, and Pickett (20) stated that prompt storage at 32° 

 to 36° F. tended to hold soft rot caused by Penicillium under control. 

 On the other hand,, Baker and Heald (2) reported that there appeared 

 to be a tendency for fruit held in the orchard for 6 to 12 days to 

 develop less decay than that stored immediately. This apparent 

 discrepancy they attributed to the fact that lenticels of the fruit 

 probably became less susceptible to invasion because of dehydiation 

 and cutinization during the delay. The histological studies by 

 Clements (4) showed that these processes can effectively close a high 

 percentage of the lenticels of the apple. 



One of the writers working with chemically treated packaging 

 materials reported 2 that 865 Delicious apples washed and packed 

 immediately after harvest had developed 194 lenticel infections when 

 examined late in January, whereas 938 fruits washed and packed 

 after 10 days in the waiehouse had developed only 30 infections. 

 Both lots had been dipped in a suspension of blue mold spores before 

 being packed. 



2 Ryall, A. L. Experiments with certaix chemicals ix packagixg mate- 

 rials for control of molds ix apples axd pears. Unpublished Progress Rpt. 

 9 pp. 1936. 



