CHAPTER LXXXI 

 APPLICATIONS OF THE PRINCIPLES OF HEREDITY 



473. Applied Mendelism. In the region about Pullman, 

 Washington, which is one of the best wheat-growing countries 

 in the world, the farmers had for years tried out many varieties 

 of wheat in order to decide which was the most profitable to 

 grow. They found only one variety that was at all satisfactory, 

 and that had serious faults. This variety was known as the 

 " Little Club " and had the advantage over others that the 

 straw was strong enough to withstand the summer storms and 

 that the head remained closed after the grain was ripened, 

 thus preventing loss before harvesting. The one great draw- 

 back of the Little Club wheat was the fact that when planted 

 in the fall, it would sometimes be frozen during the severe 

 winters (once in about every three or four years) ; and although 

 the farmers could get a better crop by planting in the fall, they 

 could not afford to lose every third or fourth planting. The prob- 

 lem was, therefore, to combine the good stem and head qualities 

 of the Little Club with the frost-resisting qualities of some 

 other variety. Mr. W. J. Spillman, of the United States Depart- 

 ment of Agriculture, at that time agriculturist of the experiment 

 station at Pullman, began a series of experiments in crossing, 

 or hybridizing, the Little Club wheat with other varieties. 



He found that whichever plant (variety) was used as the 

 pollen parent, the next generation always showed the same 

 kinds of combinations of qualities. This is in accordance with 

 what we have learned as Mendel's Law of Dominance. 



He also found that in the offspring of the hybrids every 

 possible combination of characters shown by the grandparents 

 occurred. This is in accordance with the Law of Segregation. 



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