FIXING GOOD TRAITS 



propagated indefinitely from roots or from the 

 grafting of cions; so that in practice the failure 

 to breed true from seed has little significance. 



Probably it is the fact of the relative unimpor- 

 tance that our cultivated plants should breed true 

 from seed that chiefly explains the failure of plant 

 breeders in the past to fix the type of the best 

 known fruits and vegetables and flowers. 



The same reasoning obviously applies to the 

 newly developed varieties. While so much work 

 remains to be done in the way of developing 

 new types of fruit and flower, the most practiced 

 experimenters will probably feel that they have 

 not time and energy to spare for the fixing of the 

 new races already developed. 



We shall have occasion to call attention to 

 various exceptions to this rule in the course of 

 our subsequent studies; particularly with refer- 

 ence to certain annual plants. Here by "line" 

 breeding for a few generations we may fix the 

 new traits almost as firmly as the old traits are 

 fixed in wild species. Again we shall learn in due 

 course of new hybrid fruits like the sunberry, the 

 primus berry, and the phenomenal berry that are 

 fixed as to their chief properties from the very 

 first hybrid generation. But as regards most of 

 the new forms of fruit and flower that we have 

 hitherto described, the rule holds with full force. 



[247] 



