SPELTLIKE BUD-SPORTS 

 IN COMMON WHEAT 



BY A. AKERMAN 



SVALÖ1" 



IN various forms of common wheat, Triticiim vulgare, one often finds 

 plants differing in some respects quite remarkably from the viilgare- 

 type in resembling the speltwheat, Triticiim spclta. These variations 

 (speltoids or speltoid-mutations) have been the subject for extensive 

 genetical investigations during the last years, especially by Professor 

 H. Nilssox-Ehi.p: (1917) in Li.nd. The investigations have shown 

 among other things that the speltoids are to be regarded as »loss-mu- 

 tations» arising spontaneously both in old pedigrees and among cross- 

 descendants. A distinctive character of these speltoids, which in most 

 cases have been found to be heterozygotes, is the short outer glumes, 

 abruptly cut off at the top as in Triticiim spelta. They are also more 

 strongly carinated and have more distinct nerves. In some speltoid- 

 heterozygotes the outer glumes are firmly pressed to the flowering 

 scales as is the case of Triticiim spelta. Speltoid heterozygotes are also 

 characterized by longer straws and longer and more lax spikes than 

 the mother sort.. They ripen also later. 



In the offspring of selffertilized speltoid heterozygotes there appear 

 both plants identical with the mother sort and plants identical with 

 the speltoid heterozygotes. The former are constant in the following 

 generations, and the latter repeats the segregation, which, when no other 

 forms appear, often seems to take place in the ratio 1:1. In many 

 cases, however, one also obtains homozygote speltoids characterized by 

 shorler stature and weaker growth than the heterozygotes. They have 

 also the above mentioned characters of the spikes and the outer glumes 

 more distinctly marked. These homozygote speltoids often have bear- 

 ded spikes (see this article, fig. 4). Wlien homozygote speltoids appear 

 the segregation normal type: speltoid heterozygote : homozygote speltoid 

 seldom takes place in the ratio 1:2:1. Although the segregation pro- 

 bably is simple, the number of homozygote speltoids and of heterozygo- 

 tes is often too small. According to Nilsson-Ehi.e (1917, p. 322) the 

 deviations in the segregation seem to be due to the elimination of male 



