VARIETIES OF WHEAT 



67 



obtained, whether from crossing, by selection from a field or 

 simply from the bin, seeds are planted individually in rows any 

 suitable distance apart, — usually four by four inches for spring 

 wheat and five by five for winter wheat. The larger the number 

 of individual plants the better. 

 If any plants are found among 

 those thus grown that possess 

 characteristics desirable to per- 

 petuate, one hundred seeds, more 

 or less, are planted as above 

 indicated in order to determine 

 the ability of the selected plant 

 to transmit its characteristics or 

 in the case of cross-bred varie- 

 ties by continued selection to fix 

 the t^'pe. This group of plants 

 from a single parent has been 

 given the name of centgener.^ 



Centgeners of a single strain are raised for three or more years, 

 when, if found promising, all the seed, or as much as may be 

 necessary, of the produce of the centgener, except the best one 

 or more plants, is sown in small plats to test its adaptability 

 under field conditions. If found satisfactory, the seed is rapidly 

 multiplied and distributed among farmers and commercial seed 

 growers. The plants reserved become mothers of centgeners 

 with the hope of obtaining still further improvement. 



1 Plant Breeding. By Willet M. Hays. U. S. Dept. Qf Agr., Div. of Veg. Pliys 

 and Path. Bui. 29 (i 901), p. 46. 



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Method of planting wheat in fielcl nur« 

 sery of Nebraska Experinnent Station. 

 (From photograph by Lyon.) 



