CHAPTER X 



RESULTS WITH HYBRIDIZATION 



Perhaps no cultivated plant has yielded so many inter- 

 esting results of both practical and purely scientific value, 

 as a result of hybridization, as the corn plant. Corn freely 

 hybridizes, thus offering many opportunities for the selec- 

 tion of natural hybrids. The plant is so easily manipu- 

 lated in artificial crossing, that almost any one may succeed 

 with it who would fail with other crops. Not only have 

 important results been secured bearing on the improve- 

 ment of yield in quality of corn, but also interesting scien- 

 tific data relating to the hereditary laws governing plants 

 and animals, have also been secured with com. 



DEGREES OP RELATIONSHIP 



74. When pollen of a maize plant falls from its own 

 tassel on its own silk, this is called " inbreeding." When 

 pollen from one variety is used to fertilize another variety, 

 it is called " broad breeding." There are several interme- 

 diate grades of relationship, which may be summarized as 

 follows : — 



1. Inbreeding (pollen from own tassel). 



2. Close breeding (pollen from sister plant, that is, 



plant from the same ear) . 



3. Narrow breeding (pollen from plants of the same 



variety). 



101 



