WATER CORE STUDIES ON STARKING DELICIOUS APPLES 



The effect of harvest date on the occurrence and severity of water core in 

 Starking Delicious apples was studied from 1958 to 1960. Fruit samples were ob- 

 tained from selected Starking Delicious trees on three dates during the harvest 

 season each of the three years. A random sample of fruit was immediately ex- 

 amined for water core. The amount of water core present was classified as slight 

 (less than 30 per cent), medium (30 to 50 per cent), and heavy (more than 50 per 

 cent of the cross-sectional area affected). It can be noted in Table 1 that the 

 amount and severity of water core increased with delay in picking date with the 

 exception of October 20, 1960. 



Table 1 



Per cent of Starking Delicious having water core at harvest in 1958-60 

 and per cent having water core and internal breakdown immediately after 

 removal from storage and after seven days at room temperatures. 



Apples with water core 



Internal breakdown 



The amount of water core and internal breakdown present in the Starking 

 Delicious apples after storage was determined during the springs of 1959 to 

 1961. In general, the amount of water core and internal breakdown present after 

 storage appears to be closely related to the harvest date (Table 1). The results 

 indicate that if less than 30 per cent of the cross-sectional area of the fruit 

 is affected with water core the disorder will disappear in storage and little or 

 no Internal breakdown will occur. 



In general there is no change in the amount of water core and an increase In 

 the occurrence of internal breakdown in Starking Delicious after seven days at 

 room temperature following the storage period (Table 1) . 



Scald also should be considered when determining harvest dates for Delicious 

 apples. Immature Red Delicious apples are more susceptible to scald in regular 

 storage. Thirty-seven per cent of the Richared Delicious apples harvested in a 

 test in the college orchard on September 29, 1960 had water core; however, 30 per 

 cent was slight. It can be noted in Table 2 that the water core practically 



