Bitter Pit in Apples. 409 



pits 1-3 mm. diameter and depth beneath some of the lenticels, 

 and a few larger irregular, superficial, brown, discoloured patches 

 on this side, but not on the other. When rubbed with red oil, 

 no effect was produced. Apples are not sensitive to all poisons, 

 antiseptics or disinfectants. Thus when rubbed strongly with 

 iodoform, and then wiped clean, a faint smell of iodoform was 

 perceptible, even after three weeks. A few of the lenticels 

 showed as small superficial brown spots, but no pits were 

 developed, and the pulp remained sound throughout. 



Can surface poisoning produce deep seated 

 bitter pit tissue ? 



In all the experiments on adult apples with liquid or solid 

 poisons, the effects were always produced first at the point where 

 the poison was applied, and thence radiated inwards, but in 

 normal bitter pit, the dead tissue may sometimes be deap-seated 

 without any apparent connection with the exterior. There is, 

 however, a possibility that poisons might enter in too small 

 amount to poison the resistant young apple cells, and later 

 when more deep-seated, might poison the adult pulp cells as soon 

 as their resistance had decreased sufficiently. 



As a matter of fact apples appear to grow more peripherally 

 than centrally after setting. Thus in Jonathan and Five Crown 

 apples of 1 and 1.1 cm. radius, the diameter of the central core 

 was 0.4 cm., giving ratios of 2.5 and 2.75, whereas in adult 

 ajjples the relationships were : — 



Radius of apple. R^^^"'^ ,^J^^«j;« «' Ratio. 



3 0.8 3.75 



3.7 1.2 3.03 



Hence poison originally near the surface might become deep 

 seated as the apple grew to adult size, in just the same way that 

 substances at first on the surface may in time be imbedded 

 deeply in growing wood. In the case of the apple, however, we 

 should expect to find in most cases at least, a more or less 

 prominent track up to the surface, and probably many or most 

 of those cases where so such track is perceptible, and where the 

 bitter pit tissue is entirely deep seated, are the result of the 



