364 MUTATION AND PLANT BREEDING 



ing method, can give protein analyses with accuracy comparable to or 

 better than, Kjeldhals in about 3i/9 to 5 minutes time per sample. We 

 now consider it more accurate than the Kjeldahls because it measures 

 only amino nitrogen and does not measure nitrate. This is important, 

 especially for the analysis of plots fertilized with nitrogen. This machine 

 was developed at the Regional Wheat Quality Laboratory at Pullman, 

 Washington, and is now being manufactured and further developed 

 by Dr. Doyle C. Udy, its inventor at Pullman. 



Using this equipment, we have sorted out induced variation in wheat 

 and will be able to evaluate material on a large scale. 



Another machine for rapid analyses also was developed in the same 

 laboratory. This machine, the Micromill, permits isolation of better 

 milling selections using visual identification of selections according to 

 bran cleanup. Two operators can study about 1,000 samples per day. In 

 breeding, we use 1.5 to 5 grams of seed, but we hope that we can identify 

 lines carrying promising material by recognizing one or few clean nearly 

 endosperm-free bran flakes among a bulk sample from an M 2 progeny. 



Olmo: In retrospect, would it have been more economical to produce 

 a Pallas-type barley by conventional breeding methods than by the radia- 

 tion breeding technique? 



MacKev: A strict answer to your question cannot be given, since the 

 two kinds of approaches have not been tried. I have the feeling that 

 erectoidcs types became of interest to the barley breeders first when 

 induced in a highbred genie environment. As with many other things 

 hidden in our world collections, they did not attract the breeders when 

 combined with otherwise undesirable genes and this the more so when 

 their mode of inheritance was less well explored. Now that the informa- 

 tion is available, transfers by backcross are likely to be more efficient than 

 trying to induce just the right type of erectoides characters anew in 

 another variety. 



