COMMERCIAL STORAGE OF FRUITS AND VEGETABLES 



17 



for which it is safe to store depends on the variety and when it is 

 picked, and also on whether the fruit is shipped directly to a con- 

 suming center and there stored, or is stored at shipping point for 

 a time and later shipped to market. Information on these points is 

 given in table 4. In using the table it should be remembered that 

 wide differences in keeping quality are often found in pears from 

 various producing sections of the country. 



Table 4. — Length of time at various temperatures for safe storage of certain 

 varieties of pears at shipping point and after shipment to market (1%, 19) 



Storage treatment and variety 



Length of 

 storage 

 period 



End of storage period 



Stored immediately after harvest at 36° F.: 



Months 

 1-2 

 1-2 

 2-4 

 3-5 

 4-5 

 4-7 



2-4 

 2-4 

 3-5 

 6 

 6-7 

 5-7 



2-3 

 2-6 

 2-4 

 4-6 



2-3 

 2-3 

 2-5 

 3-6 



6-7 

 5-7 



( 2 ) 



( 2 ) 



September to October. 





October. 



Bosc 



November to January. 





Do. 



Winter Nelis 



January to February. 



Easter .. .. . 



February to May. 



Stored immediately after harvest at 31° F.: 



Hardy 



October to December. 





Do. 









February. 







Easter 



Do. 



Stored after shipping without precooling, but under refrigeration 

 at 31° F.: 

 Bosc 







October to February. 







January to March. 

 October to November. 



Stored after shipping fruit precooled, and under refrigeration at 

 31° F.: 

 Hardy 



Cornice ' 





Bosc 



October to January. 



Clairgeau 



November to February. 

 March to May. 

 Do. 





Easter 



Picked in recommended range of 10 to 9 pounds: ' 



Hardy 





Picked in recommended range of 11.5 to 9 pounds: l 



Cornice 









1 Degree of firmness as indicated by the pressure tester described by Magness and Taylor (16). 

 1 Doubtful if fruit would arrive in firm enough condition to hazard commercial storage. 



The commonest and most serious decay of fall and winter pears 

 in storage is gray-mold rot, caused by the fungus Botrytis, which is 

 able to spread from decaying to sound healthy fruit. It is fre- 

 quently called nest rot. Good control can usually be obtained by 

 the use of paper wrappers impregnated with copper (4). 



Kieffer pears, if they are sound, firm, and still green in color when 

 stored and are held under the conditions recommended for other 

 fall and winter pears, can be expected to keep satisfactorily for 2 or 3 

 months. If intended for storage they should be handled with ex- 

 treme care during the picking and packing process, because even 

 slightly bruised or rubbed places are very likely to turn black and 

 seriously damage the sales value of the fruit. Recent investiga- 

 tions 3 by the Department of Agriculture have proved that a ripen- 

 ing temperature of 65° F. is essential for the attainment of maximum 

 quality in Kieffer pears for either dessert or canning purposes. 



« Unpublished data of the Bureau of Plant Industry. 

 22618°— 34 3 



