8 VALUE OF FIKST-GENEKATION HYBRIDS IN CORN. 



It was natural that investigators should follow out what appeared 

 to be the more logical and scientific method. The fact that yields 

 could be materially increased by simply crossing two varieties was 

 lost sight of. Great strides have been made in the knowledge and 

 possibilities of corn improvement by selection, but until the past- 

 few years the possibility of utilizing the vigor of first-generation 

 hybrids of corn has remained almost exactly where it was left by the 

 pioneer experimenters. 



PECULIAR HABITS OF THE CORN PLANT. 



Even after the increased vigor of first-generation hybrids became 

 recognized as a general principle it was not appreciated that the 

 peculiar habits of the corn plant made its commercial application 

 to this crop entirely feasible. Corn is peculiar among the important 

 crop plants in being wind-pollinated and in having the male and 

 female flowers on widely separated parts of the plant. This com- 

 bination of characters permits the production of crossed seed in 

 large quantities by the simple expedient of planting two varieties 

 together and removing the tassels from the plants of one variety, 

 which will then produce only hybrid seed. The importance of this 

 fundamental ditTerence between the flowering habits of corn and 

 those of other crops has not been sufficiently appreciated. Systems 

 of breeding developed for other plants have been applied to corn, 

 diverting attention from this more simple method of im})rovement 

 made possible by the peculiar habits of the plant. The use of first- 

 generation hybrids will doubtless be found applicable to other crops, 

 but in few will its utilization be so easily accomplished as with corn. 



FIRST-GENERATION HYBRIDS CONFUSED WITH HYBRID 



VARIETIES. 



The utilization of crossing as a means of securing increased yields 

 was further retarded by the failure to realize that the high performance 

 of the generation immediately following a cross is not maintained in 

 subsequent generations. Much effort has been expended in attempt- 

 ing to establish hybritl varieties, overlooking the possibilities of the 

 direct use of hybrid seed of the first generation. The fact that few 

 of the hybrid varieties have been found to have permanent value 

 should not prevent the appreciation of the vigor that immediately 

 follows the crossing. 



Until recently hybrids were usuafly made by hand-pollination and 

 the quantity of first-generation seed was necessarily small. That 

 the plants from this seed were especially vigorous and productive 

 aroused the hope that a happy combination of varieties had been 

 discovered, and attention was at once centered on the increase of the 



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