Richardson: Wheat Breeding 



131 



obviously invoh'c as little labor as 

 possible, and take up a minimum of 

 time. To be completely effective, the 

 selection must be continuous and unin- 

 terrupted, i. (?., the selection must be 

 kept up year after year to counteract 

 any tendency on the part of the wheat 

 to degenerate. 



A method which has the merit of 

 being continuous and of requiring a 

 small amount of labor is the following : — 



A field of the variety which it is 

 desired to improve by mass selection is 

 carefully inspected at harvest -time, and 

 sufficient of the best-developed heads 

 from robust, well-developed, prolific 

 plants is selected to yield, on hand- 

 threshing, about five pounds of graded 

 grain. This seed may be sown at seed- 

 time, say in 1915, in one strip of the 

 drill, on approximately one-tenth of an 

 acre, as a " stud ' ' plot. At harvest-time 

 a similar process of selection of the best 

 heads from the strongest plants in the 

 "stud" plot is carried out, and the 

 produce of the selection is reserved to 

 form the "stud" plot of 1916. The 

 balance of the "stud" plot of 1915 is 

 harvested and sown as the "seed" plot 

 of 1916 on an area of approximately two 

 acres. In 1916 the process is repeated. 

 The best selected heads of the 1916 stud 

 plot become the stud plot for 1917, and 

 the balance of the stud plot becomes the 

 "seed" plot of 1917. The 1916 seed 

 plot of two acres is harvested and sown 

 on, say, 30 to 40 acres as a "bulk" 

 plot for 1917, from which seed for the 

 whole farm is obtained. Thus, after 

 three years, the selection becomes 

 automatic. The small stud plot has 

 been selected for three years, and repre- 

 sents the "elite" plants of a race which 

 is gradually approaching a pedigreed 

 character. 



The full effects of the process would 

 not be felt for at least three years — the 

 time taken for the "stud" plot to be- 

 come the "bulk" plot. 



INDIVIDUAL SELECTION. 



The method could be made more 

 systematic by making the unit plot a 

 single row of specially-selected plants, 

 and rigorously selecting each season the 

 very best plants of each row. 



WHEAT ANTHER 



It is made up of four pollen-sacs, which 

 are about ready to burst at the 

 lower ends, releasing th^ translucent 

 pollen grains that are visible inside, 

 and letting them fall on the stigma 

 below. (Fig. 15.) 



