Aug. 6,1917 Studies on Oat Breeding 311 



As shown in Table II, the inheritance of the hull characters presents 

 a simple Mendelian relation giving i hulled, 2 intermediate, i naked. 

 Likewise, in respect to grain color, there are 3 black plants to i white 

 in the second generation. 



. As shown in Tables III and IV, the genes for these two characters 

 segregate independently of each other. 



In all cases multiflorous spikelets occur only in connection with naked 

 grain. Plants with completely hulled grain bear only biflorous spike- 

 lets. 



The inheritance of the pubescence at the base of the lower grain 

 presents some difficulties, since this character can not manifest itself 

 on plants with naked grain. By using a selected group of plants hav- 

 ing hulled and intermediate grain it is found that this pubescence 

 behaves as a bifactorial character, giving 15 pubescent plants to i with- 

 out pubescence (Table V). Neither of these genes are linked with the 

 color genes. 



The evidence available indicates that one of these pubescent genes 

 may come from the naked parent. 



The presence of long and short pubescence at the base of the grain 

 behaves as a monohybrid character and segregates independently of 

 the other genes considered. 



A remarkable feature of this cross is the presence of pubescence at 

 the base of the upper or second grain. There are no cultivated varie- 

 ties of oats which possess this character. In the present cross these 

 forms occur only on spikelets where the lower grain is naked or semi- 

 naked. It is probable that the presence of this pubescence at the base 

 of the upper grain is due to physiological disturbances caused by the 

 presence of the naked lower grain. 



The presence of awns is also affected by the nature of the glumes. 

 All naked grains bear only a thin, weak awn. On considering only the 

 hulled and intermediate types of grain, there appears to be a simple 

 3-to-i ratio between plants with medium strong to strong awns and 

 those plants with weak awns. 



LITERATURE CITED 

 (i) Fruwirth, Karl. 



1914. HANDBUCH DER LANDWIRTSCHAFTLICHE PFLANZENZtJCHTUNG. Aufl. 4, 



Bd. I. Berlin. 



(2) 



1915. VERSUCHE zuR wiRKUNG DER AUSLESE. In Ztschr. Pflanzenz., Bd. 3, 



Heft 4, p. 395-451. fig- 33-42. 

 Cites work by Christie (p. 434.) 



(3) Howard, Albert, and Howard, Gabrielle L. C 



I912-15. ON THE inheritance OF SOME CHARACTERS IN WHEAT. I-H. In 



Mem. Dept. Agr. India, Bot. Ser., v. 5, no. i, p. 1-46, 3 pi., 1912; 

 V. 7, no. 8, p. 273-285, 8 pi., 1915. 



