Edible Products. 



306 



[October, 1910. 



It is with strength of this type— the 

 strength . determined not merely by 

 climatic conditions, though possibly 

 varying a little from season to season — 

 that the breeders of this country are 

 concerned. Further, as Red Fife ap- 

 pears to retain its strength wherever 

 it is grown, it is not improbable that 

 this variety will prove to be the pro- 

 genitor of the world's strong wheats in 

 the future. Unfortunately there are 

 many drawbacks to its cultivation in 

 this country, and it is doubtful whether 

 it will ever become one of our staple 

 varieties, except possible in some few 

 localities. On many soils it is an in- 

 different cropper, and even in those 

 places in which it gives a satisfactory 

 yield the straw does not stand as well as 

 that of our common wheats, Could the 

 breeder only combine its excellent 

 quality of grain with a heavy cropping 

 capacity and stiff straw he could obtain 

 a variety which would go far towards 

 making wheat once again the most pro- 

 fitable crop of the farm. 



The solution of such a problem re- 

 quires a knowledge of the inheritance 

 of characteristics peculiarly difficult to 

 deal with. A casual mspectioo of a 

 plant is sufficient to determine whether 

 it is bearded, velvet-chaffed, red, &c, 

 but strength, yield, and stiffness of 

 straw cannot be determined so readily. 

 In fact, the single plant the breeder now 

 deals with — instead of the mass, as 

 before— gives him no information of value 

 as to capacity to afford a heavy yield of 

 grain or stiff straw. Such features can 

 only be determined by actual and, in 

 view of their number, costly field trials. 

 In the characteristic "strength" the 

 problem is not quite so complex, as by 

 choosing varieties showing extremes of 

 strength and weakness as parents, it is 

 possible to differentiate these with 

 sufficient accuracy for technical pur- 

 poses when segregation has occurred. 



The mode of inheritance of strength 

 was first determined by crossing Red 

 Fife with Rough Chaff, the former 

 parent having strong grain of a red 

 colour, the latter weak grain of a white 

 colour. Like most weak wheats, the 

 grain of Rough Chaff is soft and of a 

 texture well described as floury, whilst 

 that of Fife is hard and translucent. 

 The texture of the grain has proved 

 singularly constant under our experi- 

 mental conditions and a good index as 

 to the baking quality of flour from the 

 grain. The generation raised from the 

 plant arising from the combination of 

 the parents, the Fi., of the Mendelians, 

 showed obvious segregation into strong 

 and weak wheats, these characteristics 



being entirely independent of such 

 others as the velvet nature of the chaff, 

 the grain colour, &c. Thus in this gener- 

 ation the following obvious types 

 occurred :— 



Strong, velvet-chaffed, red. 

 do do , white, 



do smooth-chaffed, red, 

 do do , white. 



Weak, velvet-chaffed, red. 

 do do , white, 



do smooth-chaffed, red. 

 do do , white. 



On determining the proportion of 

 strong-grained to weak-grained individ- 

 uals there were found to be three of 

 the former present to every one of the 

 latter, the distribution cf the two forms 

 being uniform in the eight types men- 

 tioned above. Strength in this case, 

 then, proved to be simply dominant to 

 lack of strength. In the following sea- 

 son a number of pure stiong types were 

 isolated and grown on again the follow- 

 ing year, in order to obtain sufficient 

 grain for tests in the bakehouse. The 

 results of these tests confirmed the view 

 arrived at from an examination of the 

 grain of the F,2 generation, and left no 

 doubt that the strength of these 

 hybrids was of the same order as that 

 of the parent Red Fife. 



In many other cases the simple 

 Mendelian ratios are not so readily 

 ascertainable, owing to the varieties 

 chosen as the weak parents producing 

 semi-translucent grains. Under such 

 conditions the well-known chewing test 

 of the wheat buyer is generally sufficient 

 to show that segregation has occurred, 

 and to enable the breeder to pick out 

 the strong types for further tests. 



Whilst these investigations were in 

 progress some of the late W. Farrer's 

 Fife crosses were being obtained in 

 sufficient bulk in making tests. These 

 also proved to be " fully as strong as 

 Fife." Thus the facts at our disposal 

 seem to warrant the statement that 

 strength is a unit character. Compli- 

 cations may and probably do exist, much 

 as they do with the colour character- 

 istics of wheat, but of this nothing is 

 known at present ; so far the only 

 exception taken to this view has been 

 based on cases in which the actual 

 baking strength of the parent plants is 

 unknown. 



The strong wheats of the world are 

 at present cultivated almost exclusively 

 in countries in which the yield per acre 

 is small ; where large yields are the rule 

 the weaker types only are in genet al 

 cultivation. It has consequently been 



