samples contained relatively high concentrations, and these 

 samples developed relatively small amounts of breakdown and rot, 

 although the effect on rot was not evident in the averages on 

 Table 2 due to the presence of a couple of high-rot samples in 

 this group. There was also a significant relationship between 

 N concentration in fruit and the occurrence of breakdown, with 

 higher N being associated with lower frequency of breakdown. 



Fruit firmness is a crucially important quality character- 

 istic for apples, especially Mcintosh. It is therefore import- 

 ant to know if mineral composition of the fruit affected firmness. 

 There was no significant relationship between any of these elements 

 and fruit firmness, either at harvest or after storage. Thus, 

 differences in fruit firmness among these orchards could not be 

 attributed to differences in their mineral composition. 



In 1980 and 1981, 5 micronutrients within the fruit were 

 also surveyed: boron (B) , zinc (Zn) , manganese (Mn) , iron (Fe) 

 and aluminum (Al) . The relationships between their concentrations 

 in fruit andquality of the apples after storage were generally 

 quite low. The strongest relationship was between low B and 

 increased breakdown in 1981 (though not in 1980) , but this effect 

 was much less than that of low Ca on breakdown. 



The 4-year time period and the wide geographical distribution 

 of the orchards sampled in this survey produce an excellent view 

 of the effects of fruit mineral composition on the storage life 

 of Massachusetts Mcintosh apples. These findings indicate to 

 us that inadequate Ca in fruits is the primary nutritional factor 

 influencing quality of Mcintosh apples in Massachusetts, and that 

 this factor is expressed mostly in the occurrence of breakdown 

 after storage. Although excessive N and K in the fruit can cause 

 severe reduction in fruit quality, very few samples in our survey 

 appeared to be excessively high in these elements. Few samples 

 contained Mg concentrations that appeared to impair fruit quality, 

 and while low P did seem to be detrimental, only a small number 

 of samples contained detrimentally low P concentrations. 



The relationship between low Ca and occurrence of breakdown 

 is further illustrated in Figure 1, where post-storage breakdown 

 in each of the 172 samples was plotted against its Ca concentration. 

 Regardless of their concentrations of other elements, samples 

 very low in Ca (e.g., less than 130 ppm) almost invariably developed 

 more than 10% breakdown, which we consider to be unacceptable 

 quality. In contrast, samples high in Ca (e.g., more than 175 ppm) 

 almost never developed lO";; breakdown. At intermediate Ca concen- 

 trations, it appeared that the fruit were susceptible to break- 

 down but whether or not it developed was determined by other 

 factors, one of which may have been the concentration of another 

 element. It appears that when Ca concentration was high, the 



