Bitter Pit in Apples. 



19 



Preliminary 

 treatment! 



Immersed for : 



3 days at l(fO.- 

 ll'^C. Faint to 

 no superfi c i a 1 

 browning 



.3 days at 3U°C. 

 Brown spots 2- 

 4 mm. diameter 



Subsequent treatment for 4 da>'8 

 IO'C.-11'C. 



From superficial 

 browning to pits 

 1-2 mm. diame- 

 ter and 1 mm. 

 deep 



Pit.5 3-5 mm. dia- 

 meter and depth. 

 Pit tissue jjale 

 brown, unshriv- 

 elled and con 

 taining some liv- 

 ing plasmolys- 

 able cells 



Pit 1-2 mm. diam- 

 eter and 1 mm. 



Pits 3-10 mm. di- 

 ameter and 5-H 

 mm. deep, and 

 broader below 

 surface than on 

 skin. Tissue 

 brown and part- 

 ly shrivelled 



30X'. 

 Pits 1-3 mm. 



di- 



ameter and 1- 

 mm. deep 



Pits 6-10 mm. di- 

 ameter and tj-js 

 mm. depth, 

 partly confluent. 

 Tissue dark 

 brown and shri- 

 velled 



The influence of tenipei<iture upon the sensitivity to poison is 

 shown also by non-metallic poisons. Thus chlorot'oiia ])0uie<l over 

 the surface and then allowed to evaporate, produced brown pits 

 over the surface below the lenticels, and with a watery soluti(Mi the 

 following results were obtained : — 



Yates' Pippin. Chloroform. All showing no distinct sui)Lificial 



jsigns of poisoning after three days' inimersal. 

 temperature for four days and examined. 



Then all 



Concentration. 



1 per 1000 c.c. (shaken 

 up and excess al- 

 lowed to slowly 





 1 per 10,000 c.c. 



1 per 100,000 c.c 



3UOC 



- Pits superficial to 



2 mm. diameter 

 and depth. 



- Pits superficial to 



1 mm. deep. 



- No distinct signs 



of poisoning. 



Tomperattiros durinjf Ii 



110-120C. 



Faint to no super- 

 ficial poisoning. 



No signs of poison- 

 ing. 



No signs of poison- 

 ing. 



No distinct 

 signs o f 

 poisoning 



No signs of 

 poisoning 



No signs C'f 

 poisoning 



a distinct 



Thus a solution of chloroform capable of exercising 

 poisonous action at 30 deg. C, was non-poisonous at to 1 deg. C 

 The presence of chlorofoi-m appeared to retard the browning of the 

 affected cells, and Yates" Pippin appears to be 10 to 100 times as 

 resistant to chloroform as Jonathans. (1st Paper, p. 4()2). 



In another experiment normal apples were immersed in puio 

 chloroform for short periods of time, and then kept in air for a 

 week at the temperatures given. 



Yates' Pippin. Normal surface. Soaked in chloioforni, and 

 then kept in air for 1 week at 14—15 deg. ('.. and at 0-1 deg. ('. 

 The calvx and stalk ends clo.sed with riaraffin. 



1 5i 



