HYBRIDISATION AND WHEAT HYBRIDS 401 



fragile axis and tightly fitting glumes, though less so than the Spelt 

 parent. 



In F 2 many forms were found, some Spelt-like with red and white 

 chaff, others like ordinary wheat with white and reddish chaff, both 

 glabrous and pubescent : none were completely like either of the parents 

 first crossed. 



iii. T. vulgare, var. lutescens (Main's Stand-up), Beardless, White 

 Chaff x T. Spelta, var. Duhamelianum (Beardless Red-chaffed Winter 

 Spelt). Two constant Spelt wheats were obtained by H. Stoll from this 

 hybrid, one with white and the other with red chaff. The red-chaffed 

 form, placed on the market in 1902, has beardless ears, wide spikelets, 

 with plump, flinty grain and strong straw, and is highly resistant to frost 

 and rust. 



The following successful hybrids of T. Spelta and T. vulgare were also 

 made by H. Stoll : 



Bordier x Red Tyrol winter Spelt. 



Heine's Squarehead x Red Tyrol winter Spelt and its reciprocal. 



iv. T. Spelta, var. Duhamelianum (Beardless, Red Chaff) x T. vulgare 

 (Squarehead, Beardless, White Chaff). The F x of this cross made by 

 Miczynski had lax, beardless ears and wide spikelets. Four different 

 segregates were found in F 2 , viz. : 4 Spelta forms, 8 like F 1 ; 3 Square- 

 heads ; i compactum form or i Spelta ; 3 non- Spelta forms. 



7. HYBRIDS OF T. compactum WITH OTHER WHEATS. 



Triticum compactum x T. vulgare. Many hybrids have been obtained 

 between these races of wheats, the chief results being described below : 



i. T. compactum, var. Humboldtii (Little Club) x T. vulgare. 



ii. T. compactum, var. rufulum (Red Chaff Club) x T. vulgare. 



In 1899 Spillman crossed " Little Club " and " Red Chaff," two 

 varieties of T. compactum, with several sorts of long-eared varieties of 

 T. vulgare. 



The Fj in the majority of cases was intermediate in length and density 

 of ear between the parents. In F 2 there appeared long-eared, short- 

 eared, and intermediate plants : in some instances the numbers of each 

 approximated to the ratio i long-eared : 2 intermediate : i short-eared, 

 while in others every gradation was found between the grandparents, and 

 in addition, some examples with both longer and shorter ears than 

 these. 



Where " Farquhar " a long-eared, beardless, brown velvet-chaffed 

 T. vulgare was crossed with the beardless little Club, the F 2 in some 

 cases consisted chiefly of long-eared individuals with few or no inter- 

 mediates or compactums. 



iii. T. vulgare ? (Red King, Beardless) x T. compactum $ (Rood 

 Koren, Bearded). In 1902 Wilson crossed Red King, a long-eared, 



2 D 



