FRUIT NOTES 

 January 1956 



appij: sTQRAgr scald 



The severity of apple storage scald is greatly influenced by the type of 

 growing season. In other words, the fruit is somewhat predisposed to scald 

 before it ever enters the storage. However, there are some things a grov/er uiay 

 do to reduce its severity even in bad scald years. 



It is the purpose of this brief report to discuss sane of the factors which 

 influence scald and the value of present scald control measures. 



A, Orchard Factors: 



1, Variety . In iiassachusetts by far the most susceptible variety is 

 Cortland, This variety tends to develop scald rather early in the storage 

 season (often by December or January) and to develop a dark brown, somewhat 

 sunken type of scald. Both R, I, Greening and Rome are subject to this disorder 

 but except for a relatively fev; grc.Yers the volume of Rome and R.I. Greening in 

 Massachusetts is small. Such varieties as Mcintosh, Delicious, Golden Delicious, 



and Baldwin are not usually affected, 



2, Season . There is some indication that scald is apt to be worse following 

 growing seasons that have been warmer than usual. If this is true one would 

 expect more scald to develop this year than last. Scald on Cortland has already 

 appeared (after fruit was held at room temperature for 5 days) on k out of 11 

 samples of Cortland taken by Dr. Bill Lord from storages in six counties in 

 December, 1955* Last year Cortland did not begin to scald until February, 



3» Fertilizer Program , Actually very little experimental work has been 

 done relating nutritional status of the tree to incidence of scald, Hovrever, 

 some work has been done relating nitrogen level of the tree with severity of 

 scald. The findings from these studies do not indicate any close correlation 

 between nitrogen level and scald development. The influence of other elements 

 such as potassium, magnesium, boron, etc, is open to investigation, 



h* Maturity of the Fruit At Harvest , The influence of maturity is well 

 known. Immature apples aMost always scald more than more mature lots, 



B, Storage Factors 



1, Temperature c It is commonly stated that apples held at 32° F, will 

 scald less than fruit held at 36-I4O'' F, It is desirable to cool apples as quick- 

 ly as possible to 32° F, to reduce the rate of ripening and softening as much 



as possible. However, recent work at Amherst does not seem to substantiate the 

 claim that apples will always scald more when held at kO° F, than at 32^ F, 



2, Apple Volatiles . It is the opinion of many that storage scald is caused 

 by organic gases produced by apples. It has been possible, for example, to in- 

 crease the amount of scald on a firm lot of apples by passing vapors from ripe 



