STUDIES ON OAT BREEDING— V: THE Fj AND Fj GENE- 

 RATIONS ON A CROSS BETWEEN A NAKED AND A 

 HULLED OAT^ 



By Jacob Zinn and Frank M. Surface, 

 Maine Agricultural Experiment Station 



INTRODUCTION 



The present paper is an account of the results obtained from a cross 

 between representatives of two subspecies, the naked oat, Avena saliva 

 nvda var. inermis and Avena saliva patula var. Victor. These varieties 

 possess several contrasting characters. An examination of the Hterature 

 has failed to reveal any detailed descriptions of the inheritance of the 

 naked and hulled characters in oats. Von Tschermak (9, p. 85; 10, 

 p. 364)^ states that in a cross between a naked variety, Avena chinensis, 

 and a hulled oat the hull-less character is apparently dominant. The 

 segregation resulted in naked forms, intermediate forms, and fully hulled 

 oats. He also states that the multiflorous character of the naked oat is 

 correllated with the naked character of the grain and that the character 

 of firmly hulled grain excludes the multiflorous condition. 



It seemed probable that a more detailed study of these and other 

 characters would be of considerable interest. The present paper re- 

 ports the results obtained as far as the second generation. The main 

 characters dealt with in this article are the type of flowers and hulls 

 and the characters of the glumes (pubescence, color, awning). This 

 cross was made in 1914, and the progeny in both generations v/as grown 

 out of doors. In the absence of the data on the third-generation plants, 

 certain questions arising in the discussion could not be fully solved. 

 The great variety of intermediate forms segregating in the second gen- 

 eration is responsible for the fact that a large part of this paper is de- 

 scriptive. The more or less minute description of the parents and their 

 progeny was also prompted by the desire to give a detailed picture of 

 the forms involved, in order to facilitate the establishment of their bo- 

 tanical identity. 



Regarding the methods used, the reader is referred to the paper re- 

 cently published by one of the writers (6) . 



THE NAKED PARENT, AVENA SATIVA NUDA 



The seed of the naked parent used in this cross was secured from the 

 Russian Bureau of Acclimatization, having been originally grown in 

 the Experimental Garden of the Horticultural School at Cholmy, Russia. 



' Papers from the Biological Laboratory of the Maine Agricultural Experiment Station: No. 112. 

 2 Reference is made by number to "Literature cited," p. 311-312. 



Journal of Agricultural Research, Vol. X, No. 6 



Washington, D. C. Aug. 6, 1917 



jd Key No. Me. — 11 



(293) 



