CHANGES ACCOMPANYING BREAKING OF REST PERIOD 35 



C. SUGAR CONTENT OF TREATED AND UNTREATED 



TWIGS 



In the foregoing experiments the enzymes found in treated 

 twig tissue proved to be more active than in untreated twigs when 

 allowed to act on foreign material. 



When the tissue is ground up as was done in the preceeding 

 experiments, some of the cells are ruptured and as a result their 

 organization is disturbed. It is possible that ferments might show 

 a different behavior after being freed, than under normal proto- 

 plasmic control. 1 How do the enzymes respond to treatments given 

 the tissue, when they are allowed to act under protoplasmic control 

 in living tissue? In other words, how do they affect the insoluble 

 stored foods, especially starch, which are naturally found in the 

 tissue? To answer these questions was the main object of the fol- 

 lowing experiments. 



The material used, the manner of collecting the twigs and divid- 

 ing them into similar groups, as well as the preliminary treatments 

 given, were the same as in the foregoing experiments. 



After the twigs had received the preliminary treatments, i. e., 

 the application of the rest period breaking agent, they were ground 

 up in the food chopper. The entire twigs were used. Duplicate 10- 

 gram samples of treated and of untreated material were weighed 

 out. These were then placed in coarse filter papers. Each sample 

 was leached with 100 cc. of cold water. The water was poured over 

 the material as quickly as possible so that the entire 100 cc. was 

 added before any water came thru the filter. 



The extract passed thru the filter very rapidly so that whatever 

 material came thru must have been very soluble. In some cases a 

 second and a third 100 cc. of extract were obtained from the same 

 material, each 100 cc. being kept separate. The presence and amount 

 of sugar in the extract was determined by means of Fehling's solu- 

 tion which was prepared according to the Official Methods of Agri- 

 cultural Chemists (U. S. Department of Agriculture). Equal quan- 

 tities of Fehling's, usually 1 or 2 cc., were added to equal quantities 

 of extract, usually 5 or 10 cc. These mixtures were boiled for at 

 least two minutes after which they were allowed to cool. All deter- 



1. Palladin, W. On Respiratory Enzymes. Jahrb. f. wiss. Bot. 47, pp. 

 431-461. 



, Die Arbeit der Atmungsenzyme der Pflanzen unter ver- 



schiedenen Verhaltnissen. Ztschr. f. Physiol. Chems. 47 (1906) pp. 406-451. ^ 



, Bildung der verschiedenen Atmungsenzyme in Abhangigkeit 



von dem Entwickelungsstadium der Pflanzen. Ber. d. d. Bot. Ges. 24 (1906) 

 pp. 97-107. 



