- 8 - 



vest? How much do temperature, O2 level, and storage humidity dur- 

 ing the high CO- treatment influence benefit or injury? Can the 

 high CO2 treatments be extended beyond 2 weeks? What is the sensi- 

 tivity to CO2 of other varieties that might be in the room with 

 'Mcintosh?' 



To attempt to answer these and other questions in the shortest 

 period of time, a joint experiment has been designed for the com- 

 ing season at Cornell University, Michigan State University, Uni- 

 versity of Guelph COntario, Canada), Agriculture Canada Research 

 Station, Summerland, British Columbia, and the University of Massa- 

 chusetts. Personnel at each of these locations will conduct a 

 basic experiment with 'Mcintosh' with each institution examining 

 at least one of the above questions. 



It is hoped that this joint research approach will substanti- 

 ally decrease the length of time needed to determine the feasibility 

 of high CO2 treatment in retarding softening of 'Mcintosh. ' Exces- 

 sive softening of 'Mcintosh' is a severe problem, and the use of 

 high CO2 may be a simple approach to lessening the problem. But 

 the possibility of CO2 injury is a constant threat that will requi 

 much data and much caution before commercial trial on 'Mcintosh. ' 

 Unfortunately, we are working with a variety that appears to be 

 more susceptible to CO2 injury that 'Golden Delicious,' and we can- 

 not simply apply the results from Dr. Couey's tests in Washington 

 to our conditions in Massachusetts. 



re 



Table 1. Effects of high CO9 levels at the beginning of CA storage 

 on firmness of apples. 



*Followed by 5% CO2 , 3% O2 for duration of storage period. 



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