LUTHER BURBANK 



of its second-generation members, so that these 

 cannot breed true. 



When you wish to fix a dominant quality, there- 

 fore, you must save the seed of each individual 

 and plant it in separate plots. Only in this way 

 can you determine which individual is a pure 

 dominant, and hence will breed true. If you mix 

 the seeds of your dominants, you may go on for 

 generations, groping blindly in the effort to fix 

 a new race, without success. 



It is highly important to get these relations of 

 dominant and recessive factors in Mendelian 

 heredity clearly in mind. Indeed, the principle 

 that mutually exclusive pairs of qualities are inde- 

 pendently segregated and redistributed in the sec- 

 ond generation of a hybrid progeny doubtless ex- 

 ceeds in importance all other aspects of the 

 problem of plant development. It was through 

 independent discovery of this law of heredity that 

 Mr. Burbank was enabled to make the major part 

 of his conquests in the domain of practical plant 

 breeding. 



DEALING WITH COMPLEX FACTOBS 



If you have grasped the essential principles of 

 this Mendelian inheritance, your effort to com- 

 bine the qualities of two different varieties of 

 species of plant will represent a comparatively 

 simple experiment so long as you have only one 

 or two characters in mind. Suppose, by way of 

 illustration, that you have in your garden a gladi- 



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