112 Butler: SUGAR IN TUBERS OF SOLANUM TUBEROSUM 
It would also appear as if potatoes stored at 8°-10° C. not only 
do not accumulate sugar but do not reconvert it into starch as 
occurs at higher temperatures (this.is Miiller-Thurgau’s view of 
the matter), or dispose of it through respiratory activity. The 
amount of sugar present in the potatoes when they are placed in 
storage at this temperature suffers little change. This fact is 
clearly shown in the following table: 
TABLE II 
CHANGES IN SUGAR CONTENT OF eines ee: VARIETIES OF POTATOES AFTER STORAGE 
—11° C. FOR 34 DA 
Percentage reducing sugar in potatoes 
Variety of potato pitino At end of 34 days Increase 
prea a Snare ee re me PCOS 0.59 0.43 —0.16 
eivie anew sao 0.88 0.65 —0.23 
iti peor Nosker Seong te 0.17 0.24 +0.07 
Barly Obie 6.65 oo en ek 0.15 0.16 +0.01 
Hatiy Hpee i556 7 oe ea eee 0.42 0.31 —O.1I 
Red Alcohol 2352 62, cee 0.10 0.17 +0.07 
igloo ae ay aie elas 0.43 0.38 —0.05 
BlGe Victor se 0.53 0.45 —0.08 
MCEOCINIE F506. ke ess 0.43 0.39 —0.04 
When potatoes containing sugar are stored at 20° C. the sugar 
gradually disappears due to increased respiration and recon- 
version to starch (Miiller-Thurgau). However, if the potatoes 
remain sufficiently long at 20° C. for germination to be initiated, 
an increase in the sugar content is liable to take place. The 
aberrant results in the following table may be accounted for on - 
these grounds. 
TABLE III 
Loss OF SUGAR IN POTATOES STORED AT 20° C. FOR 2I DAYS 
Percentage reducing sugar in potatoes 
Variety of potato . ee = At end of 21 days Decrease 
REUIGNEC oir oe Sees ' 0.59 0.22 ae 
American Wonder........... 0.88 0.05 —0.83 
Rural New Yorker.......... 0.17 trace —0.17 
Barty Olio ogee ic as beecs 0.15 0.08 —0.07 
Karly Koseo oo o55 oO. 0.13 —0.29 
Red Aloghel. .. e.sSie es cys 0.10 0.15 +0.05 
Rusty Rose oo sue eos 0.43 0.37 —0.06 
Blue Lesee§ Meee wea teak 0.53 0.40 —0.13 
MOC OrINCK 56 os 5 oe eae 0.43 0.65 +o.22 
