IT4 



GRAIN BREEDING 



centgener plots is 

 compared with that 

 of each of the other 

 nine, and the grain 

 from the four plots 

 in the test giving 

 greatest yields is re- 

 tained for increase 

 plots. 



In the fourth year 

 sufficient seed is se- 

 cured from the 

 centgener plots to sow broadcast at least one square rod 

 of each variety, after casting out light seed. These are 

 called increase plots. From the increase plots sufficient 

 seed is produced to sow a tenth of an acre from which the 

 yield of grain is sufficient to seed one acre. An accurate 

 record having been kept of this process for six successive 

 years, the variety becomes a pedigreed variety. 



Head-to-row Method. This method is used extensively 

 by plant improvers, and enables the operator to select in 



Fig. 60. Planting with a centgener machine. 



Fig. 61. Increase plots of different grains. Rows from single heads at extreme right. 



