320 



The Journal of Heredity 



of a cross of smooth-awned X Club 

 Mariout a smooth-awned segregate was 

 found equal to the Club Mariout parent 

 in yield. This work was done at Moro, 

 Oregon, in co-operation with the Ore- 

 gon Agricultural Experiment Station. 

 At St. Paul, Minn., no segregates of 

 the ^Manchuria X smooth-awn crosses 

 have so far been equal to the Man- 

 churia in yield. As the senior author 

 has previously stated.' it is unlikely 

 that a parent is ever exactly recovered 

 among the segregates of a cross and it 

 is probable that weaknesses not found 

 in the ]\Ianchuria parent were present 

 in all segregates tested. 



In 1920 it occurred to the senior 

 author that, as all that was desired was 

 a smooth-awned Alanchuria, this char- 

 acter could be effectively transferred 

 to the best Manchuria strain by back- 

 crossing. C. I. No. 2330 (Minn. No. 

 184), the best Manchuria selection de- 

 veloped by the Alinnesota Agricultural 

 Experiment Station, was used as the 

 Manchuria parent. A white six-rowed 

 smooth-awned segregate from a previ- 

 ous cross was used as the smooth- 

 awned parent. This segregate was 

 homozygous for smooth awns and was 

 one of the best of those tested at Min- 

 nesota. It was already partly of Man- 

 churia "blood." 



In the winter of 1920-21 the parents 

 were crossed in the greenhouse at 

 ArHngton Experiment Farm, Rosslyn. 



Va. The Fi of this cross was grown 

 at Aberdeen, Idaho, in 1921, where it 

 was recrossed with C. I. No. 2330, the 

 Manchuria parent. The recrossed seed 

 was sown in the greenhouse in the fall 

 of 1 92 1 and the F^ generation grown 

 at Aberdeen in 1922. A smooth-awned 

 segregate in 1922 was crossed again 

 with C. I. No. 2330 and the resulting 

 seed sown in the greenhouse. The 

 status of this project today is shown 

 graphically below. 



Results Obtained to Date 



Already the barley looks more like 

 Manchuria than any obtained previ- 

 ously from other crosses. It has been 

 obtained quickly and inexpensively, as 

 the numbers used were very small. It 

 is in a way a project where the breed- 

 ing of resistance to diseases occurring 

 in Minnesota has been a factor and 

 where the actual work has been done 

 remote from this environment. It will 

 be interesting to note if resistance can 

 be obtained under such conditions. 



This opens the question of the rela- 

 tive value of the two methods of breed- 

 ing. This in turn brings up the large 

 question of the reason for the lack of 

 complete success in the earlier attempts. 

 In this case the object is to obtain a 

 smooth-awned barley as good as Min- 

 nesota No. 184 (C. I. No. 2330). 

 From the smooth-awned parent we 

 want onlv the smooth awns. All the 



Chart 1. Present Status of the Smooth Awned Barley Breeding Experiment. 



Alanchuria Lion 



homozygous segregate Fi 



Manchuria 184 



Manchuria 



Manchuria 



Fi 



I 

 F2 



Smooth awned segregate 



Manchuria 



' Harlan, Harry V. Smooth-awned barleys. Jouni. Amcr. Soc. Agron. Vol. XII, Nos. 

 6-7, 1920, pp. 205-208. 



