SELECTION AMONG WHEAT 507 



best yield of grain or of fodder, or of grain and fodder combined. 

 This plant is being especially modified for many agricultural 

 regions possessing distinctive soil and climatic conditions, and 

 is more easily adapted to locality than are most plants. 



485. Selection among wheat. Wheat of many varieties has 

 been cultivated for thousands of years throughout a territory 

 ranging all the way from China to western Europe. The origi- 

 nal home of the plant is not known, but perhaps it was in 

 Mesopotamia, between the Tigris and Euphrates rivers. In 

 Europe systematic attempts to procure improved varieties of 

 wheat by selection date back well toward the beginning of the 

 nineteenth century. Some good varieties were originated in 

 our own country in the early sixties, but more wheat breeding 

 is now done in a single year in the Agricultural Experiment 

 Station of a great wheat-raising state, like Minnesota, than was 

 done in the whole United States prior to 1890. 



It will give some idea of the extreme care with which wheat 

 breeding is now conducted to give the barest outline of the 

 mode of procedure in the Minnesota Station. 



As a beginning, 10,000 good kernels of some desirable 

 variety of wheat, old or new, are carefully chosen. These 

 grains are planted 4 inches apart (or 5 inches for winter 

 wheat), one seed in a hill, and every plant receives a number. 

 About 95 per cent of the poorer plants are weeded out by 

 hand before harvesting the seed wheat, the heads of the re- 

 maining plants are cut off, and those of each plant are preserved 

 in an envelope. After drying, the heads are weighed, and those 

 of all but a few of the best-yielding plants are thrown away. 



The second season there are sown in a separate plot in the 

 wheat-breeding nursery about a hundred seeds from each of 

 the plants chosen. Each of these hundred-groups (centgeners), 

 sprung from a single mother plant, is given a distinguishing 

 number. When the wheat is mature the relative size and 

 strength of the plants in each plot are noted and recorded, 

 and by separately harvesting and weighing each little plot the 



