1922.] Swedes Resistant to Pingeb and Toe. 967 



Keeping Qualities. — in order to test the varieties still farther 

 at Dinas, all the roots of each variety from series 1 and 2 of the 

 unlimed plots which were considered by the farmer to be sound 

 enough for use, were clamped separately and left till 14th 

 January, when they were again examined. Many of the swedes 

 had rotted so completely as to be unfit for feeding to stock. 

 These were discarded and the remainder were counted and 

 weighed. The percentage losses in weight for the differenl 

 varieties were found to be as follows: — Lord Derby 11.5; 

 Magnum Bonum 15.6; Pioneer 20.4; Dreadnoughl 13.8; Danish 

 Variety No. 4, 3.3 ; Danish Variety No. 25, 2.7. The two Danish 

 varieties thus showed much better keeping powers than the rest. 



Feeding Value-. — Finally, it was desirable to determine the 

 feeding value of the different varieties. This was done bv ob- 

 taining the percentage of dry matter, the analyses being carried 

 out by Mr. W. McLean, Lecturer in Agricultural Chemistry. 



The results are as follows : — Lord Derby S.3 ; Magnum Bonum 

 9.5 ; Pioneer 8.6 ; Dreadnought 8.7 ; Danish Variety No. 4, 10.0 : 

 Danish Variety No. 25, 10.0. The Danish varieties contained a 

 higher percentage of dry matter than the other varieties tested. 

 Since the feeding value of roots usually varies according to the 

 proportion of dry matter, it is not unfair to assume that the two 

 Danish varieties possessed a higher feeding value than the 

 British varieties. It should be noted that previous experiments 

 carried out by the University College, Bangor, have shown that 

 roots grown in North Wales generally have a lower proportion 

 of dry matter than the same varieties grown in some English 

 districts. 



General Conclusions.- It seems clear from the results ob- 

 tained that two varieties have been found which resist elubroot 

 to a marked degree, and in addition, keep better and have a 

 higher feeding value than the remainder of the varieties in- 

 cluded in the trial. This is the only conclusion one can arrive 

 at even though reliable results are only available for one year, 

 and that a relatively dry one in which the disease was less serious 

 than usual. 



An examination of Christensen's results shows that the 

 Danish varieties exhibit an oven higher degree of resistance in 

 Denmark than they do in North Wales. Tn the present inv. -li- 

 gation Danish Variety 25 is consistently more resistant fihan 

 Danish Variety 4. This is true of both the 1920 and 1921 trials, 

 and is just the reverse of the results obtained by Ghristensen. 



In assigning a value to the breeding of resistant strains it 



