54 



The Journal of Heredity 



This wild type has a brittle rachis as 

 has wild barley. The rachis is not 

 merely brittle in the sense that it breaks 

 easily as does that of emmer or spelt, 

 but it has a special articulation that 

 permits the joints to separate at matur- 

 ity. These joints are firmly attached 

 to the spikelets so that they serve as a 

 beak for the latter. Along the sides of 

 the joints are stiff bristles or hairs 

 which increase toward the upper end of 

 the joint. 



The glumes of the wild wheat are 

 very stiff, thus holding the grains very 

 tight so that they are threshed with 

 difficulty. These are some of the main 

 differences between the head of the 

 \vild wheat and that of common wheat. 

 The plant of the wild wheat is different 

 from that of the common wheat, the 

 stems being finer and the leaves nar- 

 rower. The foliage is of a lighter green 

 color than ordinary wheat. An illus- 

 tration of the wild type of spikelet is 

 shown in the frontispiece. 



MATERIAL 



While engaged in studying inherit- 

 ance in wheat from various crosses our 

 attention was attracted particularly to 

 one, a species of cross between varie- 

 ties of the common and durum types. 

 From this cross, forms resembling the 

 wild type were obtained among the seg- 

 regates in Fg. 



This cross is one made between T. 

 vulgar e var. Early Red Chief and T. 

 durum var. Marouani. The Early Red 

 Chief variety was a typical T. vulgarc 

 form, was beardless, had smooth brown 

 chaff and a red kernel. The Marouani 

 was a typical durum form, was 

 bearded, had a smooth white or yel- 

 lowish-white chaff and yellow or yel- 

 lowish-white kernel, which for this 

 study can be considered colorless. C. 

 R. Ball, who has examined this type, 

 says that it is more like an intermediate 

 between Pelessier and ]\Iarouani. The 

 sort used had black awns which, ac- 

 cording to Ball, the true Marouani does 

 not have. At the base of the spikelet 

 of the Marouani are a few hairs or 

 bristles. 



The Fj type produced from this 

 cross was intermediate , in regard to 

 certain characters. There were a few 

 very short beards at the tip of the head 

 which had some black coloration, but 

 were not nearly so black as those of 

 the Marouani parent. The glumes were 

 longer and stififer than in the female 

 parent, but not so long as in the male. 

 They were pointed at the tip more like 

 the Marouani variety. The kernel was 

 somewhat longer than that of the 

 female parent and was red in color. 

 On the joints of the rachis are a few 

 very short bristles or hairs. 



The parent types and F^ are shown 

 in Fig. 1. The F^ type is the form 

 shown between the two parent forms. 



The second generation was grown in 

 the greenhouse and 113 plants resulted. 

 Among these plants various forms 

 were produced, as is usual among 

 crosses between common and durum 

 wheats. Some of these forms are 

 shown in Fig. 2. While it is not planned 

 in this paper to discuss fully the re- 

 sults as to different forms and char- 

 acters, a short statement regarding 

 some of the results may be of interest. 



In regard to the color of chaff there 

 were in this generation 107 brown chaff 

 to 6 white chaff plants, thus indicating 

 a 15: 1 ratio. The color of kernel was 

 noted on all plants that produced ker- 

 nels and these gave 77 red : 5 white 

 kernels. This would indicate a 15:1 

 ratio for the color of kernel also. In 

 regard to awns there were 83 awn- 

 less : 30 fully awned plants, which indi- 

 cates that the awned condition is re- 

 cessive and inherited on a 3:1 basis. 

 It is well to state, however, that among 

 the 83 plants designated as awnless 

 there are some with a few very long 

 awns on some of the spikelets. The 

 fully awned plants are those that pos- 

 sess awns like the ordinary varieties of 

 awned wheat, while some of the awn- 

 less plants with long awns have them 

 only at the tip. One plant in particular 

 had awns developed at the tip of the 

 spike only, yet they measured 10.8 cm. 

 in length, while the longest awns found 

 on any of the plants were only 13.7 cm. 



