192 



The Journal of Heredity 



the occurrence of the dwarfs is given 

 except that there was no evidence of 

 hybridization. Love and McRostie (4) 

 report forms similar to naked oats, 

 which, they indicate, may have origi- 

 nated through mutative changes. In 

 a pure line of Sixty-Day, spikelets ap- 

 peared similar to true naked forms. 

 The kernel was loosely held in the 

 glumes and an increased number of 

 flowers developed per spikelet. When 

 sown, these seeds produced plants 

 which did not reproduce this naked 

 tendency. Garber (3) describes forms 

 of false wild oats appearing in Vic- 

 tory, Garton No. 784, and Aurora, and 

 states that "these aberrant forms may 

 be attributed more logically to muta- 

 tions than to natural crossing." 



Summary 



Numerous reports on controlled 

 crosses of hulled X naked oats have 

 been published. All of these reports 

 have shown segregation in the second 

 hybrid generation in the ratio of i 

 hulled : 2 intermediate : i naked. A 



total of fifty-nine progeny plants of 

 the variant multiflorous forms was 

 grown in 1921, and 300 progeny plants 

 were grown from these in 1922. Varia- 

 tion in the characters of the covered 

 kernels of the progeny plants has been 

 noticed, but as yet only one case of 

 segregation of the plants into either 

 the hulled or naked forms has oc- 

 curred. The one apparent segregate 

 was an under-developed individual and, 

 except that it bore only naked kernels, 

 closely resembled the other plants of 

 the variant type. 



It is difficult to explain the origin of 

 the multiflorous variation in Burt oats 

 on the basis of natural crossing, al- 

 though natural crossing is believed to 

 occur in oats to some extent. The 

 genetic behavior of this variation is 

 not in agreement with the results of 

 those who have reported on crosses of 

 hulled X naked oats. It appears, 

 therefore, that this intermediate multi- 

 florous variation may have resulted 

 from mutation rather than by natural 

 hvbridization. 



Literature Cited 



fi) Caporx, a. St. Clair. The Inheritance of Tight' and Loose Palea in Accna nuda 

 crosses. Jourl. of Genetics, v :22g-2^6. 1918. 



(2) Gaines, E. F. Inheritance in Wheat, Barley and Oat Hybrids. Wash. Agr. 

 Expt. Sta. Bui. 135. 1917. 



(.3) Garber, R. J. The Origin of False Wild Oats. Jourl. of Heredity, xiii :40-48. 1922. 



(4) Love, H. H., and McRostie, G. P. The Inheritance of Hull-Lessness in Oat 

 Hybrids. Ameriean Naturalist, liii:5-32. 1919. 



{5) Nilsson-Ehle, H. Spontaneous Omission of the Color Factor in Oats. Vcr- 

 handl. Naturf. Ver. Brunn, xlix (1910) pp. 139-156, figs. 4. Abs. in Expt. Sta. Record, 

 xxix 739. Dec. 1913. 



(6) Norton, I. B. Notes on Breeding Oats in America. Amer. Breeders' Asso. Rpt., 

 iii :28o-285. 1907 



(7) Warburton, C. W. The Occurrence of Dwarfness in Oats. Jour. Amer. Soc. 

 Agron., xi :y2-y6. 1919. 



(8) ZiNN, Iacob and Surface, Frank M. Studies on Oat Breeding, V. The Fi 

 and F:; Generations of a Cross Between a Naked and a Hulled Oat. Jourl. Agr. Research, 

 x:293-3i2. 1917. 



