question, we must examine the temperature range tolerance o£ the 

 Medfly. At a constant 30°F, the adults die within 100 hours, 

 and few survive more than 12 days at 45°F. The eggs cannot 

 develop unless the temperature is above 52°F. The larvae are 

 incapable of growing at temperatures below 50°F. The pupa is 

 the most cold resistant stage. But if Medfly pupae are subjected 

 to 32 F for 4 consecutive days, or to 42 F for 10 consecutive 

 days, few, if any, can survive. Thus, under normal winter con- 

 ditions in Massachusetts, no Medflies can be expected to survive, 

 just as they cannot normally survive in central Europe. However, 

 should a very mild winter occur, a few individuals might possibly 

 survive in the most temperature parts of the state, that is, 

 areas near the ocean. Even if this were to happen, however, 

 chances are the infestation would be wiped out by colder temperature 

 the next winter. 



To conclude, it is conceivable that should Medfly larvae in 

 infested fruit accidentally.be introduced into Massachusetts in May 

 or June, then the adults which they produce could lay eggs in 

 locally-grown fruits, especially stone fruits, and establish a 

 population for one or two generations before winter sets in. This 

 population would probably be restricted to a small area around the 

 site of introduction. Unless there were to be a dramatic shift 

 in climate toward very warm winters, however, it is extremely 

 unlikely that the Medfly could become firmly established in any 

 part of our state. 



Postscript: Would it be a fair exchange if California were to 

 send us the Medfly in return for our sending them the apple maggot 

 fly? In fact, the apple maggot fly, for the first time ever west 

 of the Rockies, was discovered in Oregon in 1979 and now sits just 

 a few miles north of the California border. It could become a 

 real threat to California apples, and numerous red sphere traps 

 and baited yellow rectangle traps are currently in use in apple 

 growing regions of northern California to detect any possible 

 apple maggot flies. If there had to be an exchange between these 

 two pests, I think we would get the better of the deal, given our 

 cold winters. 



WHAT'S HAPPENING IN CA STORAGE RESEARCH? 



William J. Bramlage 

 Department of Plant and Soil Sciences 



To answer this question, the Third National Controlled 

 Atmosphere Research Conference was held July 22-24, 1981 at Oregon 

 State University, Corvallis, Oregon. Approximately 100 people 

 participated in this Conference, including numerous researchers 

 from the U.S. and Canada, researchers from a number of other 



