SELECTION 



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the remnant system of corn breeding at the Ohio Experiment Station 

 and the plan was adopted by the Ohio Corn Improvement Association. 

 The plan calls for an ear-to-row test plot each year in which ears are 

 carefully tested for productiveness. Only half of the grains on each 

 ear are planted in the test plot, the remainder being retained until the 

 following year under the term "remnant." The ear-to-row test plot 

 need not be isolated as no seed is saved from it. The next year the 

 remnants of a few, usually four, of the highest yielding ears are planted 

 in an isolated breeding plot, and the stalks from all of the ears planted 

 in this patch, except those of the highest yielding ear, are detasseled. 

 Seed ears are selectad from the detasseled rows and grown the next 



FIG. 136. Delta Farm White Dent, a superior strain of maize adapted to the bottom 

 lands of the interior valleys of California. It is the result of 30 years of continuous selection 

 of seed in the field before harvesting. The original material consisted of a mixture of all 

 the types of corn commonly grown at that time. A convincing demonstration of the prac- 

 tical value of seed selection as a general agricultural practice. 



year in a multiplying plot to supply seed for general planting. After 

 this method is under way on any farm, there is maintained on the farm 

 each year a small isolated breeding plot, a multiplying plot, and an 

 ear-to-row test plot. This method successfully excludes from the breed- 

 ing plot all individuals except those whose producing power has been 

 found to be very high. At the same time it provides for the intercrossing 

 of these most productive strains, and by continuing the tests from year 

 to year the work will "tend toward the selection of the best producing 

 ears for all or average seasons." According to Hartley, "The choice 

 of a high yielding variety is important; the choice of high yielding ears 

 is even more important." The remnant system combines this result with 

 the advantages attendant upon intercrossing of distinct strains. Rye, 

 clover, beets, timothy and other grasses are suited to this method of 

 breeding. It was with rye that Rimpau first employed the system 

 that later came to be known as the German method of broad breeding. 



