CHAPTER X. 



IMPROVEMENT OF PLANTS. 



'* Those tvho improve plants are true benefactors." 



— GOFF. 



Variation, heredity, and selection form the 

 basis of all plant improvement. 



1. Variation. — It is evident that the first re- 

 quisite toward the improvement of plants must 

 be the power to vary ; for were it not possible 

 for plants to vary, no change could take place. 

 It is these individual differences that make one 

 plant more desirable than another, and \\i2iX. fur- 

 nish the starting-point for the improvement of 

 the existing type, or for the oinginatioji of a new 

 variety. 



2. Heredity, — While variation furnishes the 

 starting-point, the desired characteristics would 

 be of no avail in plant improvement were it not 

 possible for them to be transmitted by heredity. 



3. Selection. — By continued selection through 

 a number of generations, the characteristics fur- 

 nished by variation are preserved and accumu- 

 lated through heredity. 



^.—IMPROVEMENT OF EXISTING TYPES. 



When the object desired is simply to improve 

 a given variety, individual plants can be found 



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