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PHOTOGRAPHS OF NUTRIENT DEFICIENCIES AND TOXICITIES AND HEAT STRESS 



William J. Lord 

 Department of Plant and Soil Sciences 



In the past, we occasionally published in FRUIT NOTES photographs of nutrient 

 deficiencies. Last year when we had numerous problems - severe scab outbreak in 

 some orchards, hail, russetted apples, small fruit, an extremely wet spring, a dry 

 summer, slow color development on fruit of some varieties, etc. - it became apparent 

 that confusion existed concerning nutrient deficiency symptoms. Deficiency symptoms 

 recognition that caused problems were mainly boron (B), potassium (K) and magnesium 

 (Mg). Therefore, for your information we have again published photographs and brief 

 descriptions of some nutrient deficiencies of apples and pears. 



Calcium (Ca). Bitter pit and cork spot are visual evidence of low Ca in apples and 

 are more prevalent on some varieties and years than others. Bitter pit is common 

 on Cortland, Baldwin and Northern Spy whereas cork spot is much less prevalent but 

 can be found on Delicious and Golden Delicious in New England. 



The Delicious on the left in Figure 1 shows bitter pit and the one on the right 



Figure 1. Symptoms of calcium deficiency on Delicious fruit. 



