PERPETUATING A NEW VARIETY 



203 



propagation there is little chance for reversion ; as we 

 have said in Chapter XII, the offspring resemble the im- 

 mediate parent much more surely and fully than in prop- 

 agation by seeds. Mr. Bull did not have any part in 

 producing the first Concord, but he did have an essential 

 part in preserving and propagating it. 



We are ready now to see the three different ways in which 

 the plant breeder makes heredity aid him in propagating a new 

 plant that he has produced. 



(1) He must guard his new plant carefully against 

 cross-fertilization with plants of the old variety from 

 which it came. Every 



corn breeder knows the 

 need of this care. 



(2) He must watch 

 several generations of 

 the new variety, if it 

 is propagated by seed, 

 selecting from each 

 generation, for further 

 propagation, only those 

 individuals that are true 

 to the new type, and 

 destroying those that 

 show a " reversion " to 

 the old type. This work, 

 too, is part of the work 

 of every corn breeder, 

 and of every farmer who 

 tries to improve his seed. 

 After a few generations 

 of plants, such care is 

 less necessary, because 



IMPROVED CRAB APPLE. 



