1916] PRITCHARD—SUGAR-BEET BREEDING 451 
can say at present is that family differences of this character as 
detérmined by current field methods are not permanent. 
DETERIORATION FROM LACK OF SELECTION.—There is a current 
belief that sugar-beets deteriorate in percentage of sugar when 
selection is discontinued, but this has not been proved satisfac- 
torily. A gradual decrease for a limited period is not necessarily 
indicative of permanent reduction, as such environmental factors 
as sunshine, temperature, rainfall, time of planting, fertility of the 
soil, drainage, and cultural methods all vary in different years and 
these variations affect the percentage of sugar. In fact, the per- 
centage may fall for 2 or 3 consecutive seasons and then rise again ~ 
under more favorable conditions. 
If sugar-beets deteriorate from lack of selection, commercial 
seed should produce poorer roots than seed of selected mothers, 
as it is grown from an intermediate steckling generation in which 
no selections are made. Such a comparison was made in 1913 
by mixing seed of highly selected families of Morrison’s Klein- 
wanzleben and planting it in alternate rows beside the commercial 
variety of the same stock. The results are shown in table XXXIII. 
TABLE XXXIII 
Comparison OF MorRISON’S COMMERCIAL SEED WITH SEED OF MorRISON’S SELECTED 
MOTHER BEETS 
Morrison’s SELECTED MOTHER-BEET SEED } MOoRRISON’S COMMERCIAL SEED 
Row Number of aa of | Percentage Row | Number of | Weight of | Percentage 
number a in of pa ot eae cc — in ry san ag —" 
ce 
Bat iek 68 46.5 fe ae | A ae 67 43-5 15.9 
Bis ive. 68 37.0 15.0 RES OE 65 32.5 15.2 
OA. 60 39-5 15.2 ee 62 37-0 15.4 
Aen ee, 72 40.0 15.0 Goin 70 39.5 ¥§-5 
epee 62 38. ee it. 72 43.0 15.3 
| Teen 82 470 ta Eas... 69 36.5 15.7 
7 Pees 85 49.5 oO. Ge 57 33.0 ee 
Bs avy 5 74 .0 14.9 Dears ° ° , 
Averages 71.4 Ho eS Fie 66 38.0 15.5 
MS, 
Average weight of root in grams: Morrison’s commercial, 259.91; 
In every instance the commercial seed produced the richer 
roots. They were somewhat smaller than the roots from seed of 
selected mothers, averaging 11.79 gm. less per plant, but this is 
