42 6 TUKEY 



easily and so effect the cross-fertilization from selected inbred lines to 

 produce seed stocks with hybrid vigor and other desired characters. But with 

 many other plants which carry both male and female parts in the same 

 flowers, as the onion, snapdragon, tomato, petunia, and carrot, the tedious 

 separation of male and female parts has made hybrid seed expensive and 

 difficult. Here again, however, the plant breeder has used his scientific skills 

 effectively. He has located individual plants which are by nature male-sterile, 

 as with male-sterile onions. He has found ways of producing lines of male- 

 sterile onions, which when planted with selected male-fertile lines produce 

 an abundant supply of hybrid onion seed. Other vegetable and flower plants 

 are responding to this approach, promising to revolutionize the seed trade. 



The plant breeder has learned, also, that certain varieties when used as 

 parents tend to stamp their offspring with desirable characters, while others 

 are inferior sires. He knows that the Deacon Jones apple transmits size, that 

 the Mills grape transmits high quality, and that the Lloyd George red rasp- 

 berry and the Premier strawberry are superior as parents. On the other hand, 

 the Baldwin and Rhode Island Greening apples and the Seckel pear, though 

 desirable in themselves, are most inferior parents. 



It may not be out of place to comment on the importance of the variety 

 and of those who serve by the creation of improved sorts. The variety is the 

 keystone of the industry. It is to the fruit industry what the new model is to 

 the automobile industry. Until the Concord grape, there was no grape culture 

 in America worthy of the name. The Bartlett (Williams) pear is the basis of 

 pear production, and the Montmorency cherry is virtually the entire sour 

 cherry industry. 



In Michigan prior to 1920 there were hundreds of acres of unproductive 

 land on which lived families of low income. The creation of new varieties of 

 blueberries by scientific plant breeding has developed an industry now ap- 

 proaching 4 million dollars in annual crop sales. A breeding program in 

 apricots promises to establish an apricot industry, and a red-centered straw- 

 berry suited to southwestern Michigan will ensure the maintenance of can- 

 ning and freezing outlets. It is apparent that plant breeding must become 

 increasingly more local. The general-purpose variety is useful, and that is 

 what is aimed at, but the future implies a variety not necessarily for a con- 

 tinent, nor for a large region, but rather for a given purpose in a restricted 

 locality. It implies breeding, not alone for specific details of improvement, 

 but with great imagination for entirely new industries. 



Pollination and fruit set. As recently as the 1890's, pollination and 

 fruit set were little understood by commercial fruit growers and their impor- 

 tance was poorly appreciated. Compatibilities and incompatibilities are now 

 better known. No one today would plant a solid block of Delicious apples, 

 Bartlett pears, Windsor sweet cherries, or J. H. Hale peaches. These varieties 

 have been found to be self-unfruitful for one reason or another. The modern 



