1920] OVERHOLSER &• TAYLOR— TEMPERATURES 295 



I 



8. As would be expected, there was a comparatively large 

 loss from >rot with the fruit kept at high temperatures and sur- 

 rounded by high relative humidity. 



9. A possible explanation of the effects of high temperatures 

 may lie in the influence upon the enzymes. Temperatures 

 approaching the probable minimum (around 28 F.) on the one 

 hand, and the probable maximum (around no° F.) on the other, 

 might result in a reduction of enzymatic activities of the fruit and 

 a consequent retardation of the ripening processes; while with the 



optimum temperatures (70-85 F.) the enzymatic activity would 



be most marked, and hence the ripening most rapid. 



10. If the Bartlett pears have nearly reached a stage of complete 

 ripeness, the temperatures above 70 F. do not check the ripening 

 process. On the other hand, the ripening and breakdown are more 

 rapid with each appreciable rise in temperature. 



n. Unripe Easter pears behave in a manner comparable to 

 the Bartlett when placed under similar conditions of high temper- 

 atures and relative humidity. 



12. The process of ripening with Yellow Newtown apples is 

 not delayed by temperatures above 32 F. The ripening takes 

 place with increased rapidity with each appreciable rise in temper- 

 ature above 32 F. This is true with temperatures up to a point 

 which result in the disorganization of the protoplasmic contents 

 of the cells. 



13. The experiments suggest that with an excessively hot 

 season during the time of ripening, Bartlett and Easter and 

 possibly other pears might be allowed to remain on the trees 

 somewhat longer than with a normal season. 



14. For Yellow Newtown and no doubt other varieties of 

 apples, which are to be stored any length of time, the necessity of 

 quickly cooling after harvesting is emphasized. 



ft 



University of California I 



Berkeley, Cal. 



LITERATURE CITED 



/ 7 



Meteorlogiq 



£tudes 



Ann 



2. Balls, W. L., Temperature and growth. Ann. Botany 22:557-592. figs 

 n. 1918. 



