7 i6 SCIENCE PROGRESS 



being an indication of considerable value. The flour was then 

 tested in the bakehouse under the usual experimental conditions. 

 Throughout the various operations it was evident that strong 

 wheats were being dealt with, and the marks assigned to the 

 loaves left no doubt about this. They were as follows : 88, 84, 

 84, 84, 70, and 45, or four of the six tested were fully equal to 

 the blended flours known as London Households. The strong 

 parent was estimated to have a strength represented by 80-90, 

 whilst the English parent would mark at 55 or 60. The variety 

 earning 45 marks offers a certain amount of difficulty. Two 

 seasons previously it had been selected more for cropping 

 capacity and other features than its strength. There was then 

 some doubt as to its actual baking value : in the following 

 season after some hesitation it was selected for further trials, 

 and produced a crop of grain which appeared to be satisfactory. 

 The test of the bakehouse negatived this view, however, and 

 45 must be taken to represent the strength of the English 

 variety under the somewhat unfavourable conditions in which 

 it was grown and harvested. That marked at 70 is being 

 further tested ; it is in all probability a mixture of dominant 

 strong and recessive weak wheats. 



A considerable number of these strong hybrids have been 

 grown, and they include types showing all the possible com- 

 binations of the characters present in the parents. Attention 

 has to be directed to one of these, namely, cropping capacity. 

 The two parents differ markedly in this respect, for the strong 

 one only produces about one-half the crop of the English parent. 

 At present little is known as to the inheritance of cropping 

 capacity, and it is proving a difficult character to investigate. 

 Under these circumstances it is satisfactory to find that some 

 of the hybrids grown under the same conditions as a control 

 plot of the strong parent produced double the quantity of 

 grain to the same area. In fact, many of the varieties would 

 have passed muster as the English parents had the grain not 

 been examined. This negatives the view so often brought 

 forward by those who prefer speculations to actual experi- 

 ment, that strength is associated with diminished yielding 

 capacity. The evidence, then, shows that the inheritance of this 

 intangible feature strength can be traced with sufficient certainty 

 for the plant breeder's purposes, though it cannot yet be claimed 

 that the whole of the details are known. 



