May, 1921. 



SCIENTIFIC AGRICULTURE 



219 



mine the beard of a smooth-bearded barley. These 

 beards are so smootli that they may be drawn over the 

 face in ' either direction without roughness being ap- 

 parent except perhaps near the tip. 



Tlie question may be raised: "Why not remove the 

 beard entirely and thus ilo away with the barb?" In 

 answer, it may be said tliat many successful attempts 

 have been made, witli the result tluit many varieties of 

 beardless barleys have been produced. It is unfortunate, 

 but true, liowever, that in every instance, at least so far 

 a.s it has been p()ssil)le to ascertain, the net result is to 

 improve the handling and feeding (pialities of the barley 

 at the expense of its productiveness. There is a strong 

 feeling too, among plant physiologists, that the beard 

 is an essential organ to tlie barlej' plant and to remove 

 it interferes with the vital processes of the plant, thus 

 reducing production. 



Zoebl and Mikosch (2) in 1892 showed tluit tlie awn 

 of barley was an organ of transpiration. Schmid (3) in 

 1898 and Perlitus (4) in 1908 elaborated the experi- 

 ments of Zoebl and Mikosch. Tedin of Sweden (5) also 

 made observations wliieh point to the important physio- 

 logical function of the awn. These investigators are 



a. 



e. 



Scrtio)! of (a) siiioolh and (b) rough awm of hnrhif 

 (afler Rcgrl). 



agreed that the awn is an organ of transpiration and all 

 showed the effect of its removal on the kernel. 



Anothei- very exhaastive' piece of research that bears 

 out these facts is that of 11. V. Harlan and S. B. An- 

 thony (0). The following summary statement is given 

 \)\ these investigators : — 



' ' The removal of the awns from a barley spike has a 

 marked effect on the develoinnent of the kernels of the 

 si)ike. 



"Kernels from clipped spikes have snuiller volume 



and a lower weight of dry matter at maturity than do 

 those from normal sjjikes. 



"The difference is not due to the injury of shock in 

 removing the awns; the kernels in the clipped spikes 

 develop as rapidly as those in the normal spikes for 

 several days after the awns are clipped. 



"About one week after flowering the de|)osit of dry 

 matter in the kernels of the normal spikes begins to ex- 

 ceed that in the kernels of the clipped spikes. This is 

 about the time that rapid infiltration begins. 



"In normal spikes at Aberileen, Idaho, the awns con- 

 tained more than ;i() per cent of ash at maturity. When 

 the awns were removed a part of this ash apparently 

 was deposited in the raehis. The rachises of the clipped 

 spikes contained about 25 per cent, more ash than the 

 rachises of the normal spikes. 



Since the plant physiologist has by these facts clearly 

 shown that the beard is an essential oi-gan in optimum 

 development in the barley kernel, the i)lant breeder must 

 accept these and act accordingly. 



It seems rea.sonable to conclude, therefore, that the 

 removal of the beard or awn will not be the most econ- 

 omical method of solving this serious menace to the 

 barley crop. Some other means must be employed, and 

 the plant breeder has chosen that the better alternative 

 is to preserve the beard or organ of respiration but 

 remove if possible, its objectionable roughness, the barbs 

 or teeth. 



We believe that the production and distribution of a 

 barbless or smooth-awned barley will create nothing 

 short of a great boon to the barley crop — it will popula- 

 rize it. It is our conviction that yield being equal, farm- 

 ers would prefer the barbless bearded or smooth-awned 

 barley and, if a high yielding one can be found the 

 acreage devoted to barley in northern areas in Western 

 Canada will be increased many fold. 



Smooth-awned barleys are not new. Koerneeke (7), 

 described the liorrhynchum form in 1882. He also des- 

 cribed medicum and persieum, both 2-rowed sorts that 

 were found in mixtures of barley in Asia Minor. 

 Robert Regel in Russia published a monograph on 

 smooth-awned barleys in 1909. 



The Office of Cereal Investigation of the United 

 States Department of Agriculture has studied these 

 forms for several j-ears. Much breeding work has been 

 carried out co-operatively between the Minnesota Sta- 

 tion and the United States Department of Agriculture, 

 with fair results. Many smooth-awned forms have been 

 introduced from Russia, Algeria and Asia Minor through 

 the Office of Foreign Seed and Plant Introduction and 

 used in breeding experiments to produce protluctive 

 smooth-awned varieties. 



Most of the breeding work in America has been con- 

 ducted at St. Paul, Minn.; Arlington Farm, Virginia; 

 Chico, Cal. ; Aberdeen, Idaho ; and Moro, Oregon. For 

 the most part, however, liigli yielding sorts have not as 

 yet been produced. During the summer of 1918 barley 

 breeding work was undertaken by the De|)artnu'nt of 

 Field Husl)andr\', I'niversity of Alberta, with the end 

 in view of i)roduciiig a smooth-awned barley, which 

 would be suited to conditions in Alberta. Some forty or 

 fifty crosses were made, using the smooth-awned pa- 

 rents. Lion and hybrids obtained from Miinie.sota, on 

 our most i)ro(luctive (i-rowed and 2-rowed varieties, 0. 

 A.C. #21 and Canadian Tiiorpe rcsiiectively. Our re- 

 sults so far are very encouraging. A large number of 

 promising crosses have been carried forward to the 

 third generatiim, by the aid of greenhouse facilities. 



