SWEET-POTATO STORAGE STUDIES. 



17 



COMPARISON OF THE KEEPING QUALITIES OF FOUR IMPORTANT 

 COMMERCIAL VARIETIES OF SWEET POTATOES STORED UNDER 

 LIKE CONDITIONS. 



Experiments were begun in 1917 to determine the relative keeping 

 qualities of the more important commercial varieties of sweet 

 potatoes. The Southern Queen, Nancy Hall, Big-Stem Jersey, and 

 Porto Kico varieties were used in this experiment, and the purpose 

 of the workers was to store these in bins in sufficiently large quan- 

 tities to be comparable with commercial conditions. (Table 8.) 



Table 8. — Comparison of the keeping qualities of four standard varieties of 

 sweet potatoes stored in bins. 



[Shrinkage and decay averages at a temperature of 50° to 55° F. during four seasons.] 





Room 

 No. 



Weight at— 



Loss in 

 weight. 



Shrink- 

 age. 



Weight of 

 decayed 

 potatoes. 



Decay. 





Variety and year. 



Harvest 

 time. 



End of 

 storage 

 period. 



Time in 

 storage. 



Southern Queen: 



1917-18 



[ Pounds. 

 3 2,512.50 

 3 3,349.00 

 3 1 2,217.81 

 3 1 - 498. 75 



Pounds. 

 2, 119. 37 

 2, 947. 81 

 1,984.75 

 1, 397. 25 



Pounds. 

 393. 12 

 401.19 

 233.06 

 101. 50 



Per cent. 

 15.65 

 11.98 

 10.51 

 6.77 



Pounds . 



20.56 



6.50 



8.94 



2.00 



Per cent. 



0.82 



.19 



.40 



.13 



Days. 

 171 



1918-19 



172 



1919-20 



159 



1920-21 



164 







7 





Total 





9, 578. 06 



8, 449. 19 



1, 128. 87 





38.00 







Average 





11.79 



.40 



166* 





3 

 3 

 3 











Nancy Hall: » 



1918-19 



3, 970. 56 

 1,657.62 

 1,498.50 



3, 506. 69 

 1, 528. 37 

 1,407.12 



463.87 

 129. 25 

 96.37 



11.69 



7.80 

 6.43 



19.94 

 13.25 

 11.75 



.50 

 .80 

 .79 



172 



1919-20 



159 



1920-21 



165 







Total 



7, 126. 69 



6, 442. 19 



689. 50 





44.94 







Average I 



9.67 



.63 



165J 





3 

 3 

 3 

 3 











Hig-Stem Jersey : 



1917-18 



1,931.50 

 1,070.31 

 2, 533. 41 

 1 , 498. 25 



1, 699. 50 

 3, 473. 69 

 2,175.25 

 1, 384. 50 



232. 00 

 596. 62 

 358. 19 

 113. 75 



12.01 

 14.66 

 14.14 

 7.59 



91.94 



39.25 



87.31 



1.50 



4.76 

 .96 



3.05 

 .10 



171 



1918-19 



172 



1919-20 



159 



1920-21 



165 







Total 



10,033.50 



8, 736. 94 



1,300.56 





220.00 







A verage 





12.96 



2.19 



166f 





3 

 3 











Porto Rico: * 



1919-20 



2, 429. 06 



1 , 197. 50 



2,111.31 

 1,336.50 



317. 75 

 161. 00 



13.08 

 11.42 



18.00 

 5.25 



.85 

 3.50 



151 



1920-21 



166 







Total 



3, 726. .56 



3, 447. 81 



478. 75 







.62 





Average 





12.82 



158 J 















1 Results for three years only. 



2 Results for two years only. 



For the Southern Queen the average storage period was 161 i days, 

 the average shrinkage 11.70 per cent, and the average decay 0.40 per 

 cent. The figures for the Nancy Hall are for three years only and 

 show an average shrinkage of 9.67 per- cent and 0.63 per rent decay 

 for the average storage period of ior>i days. The work- on the Big- 

 Stem Jersey was carried on for four years and showed 12.96 per cent 



