Durham Carrot 



The Hutchinson variety of carrot is popular with market gardeners in New 

 England because of its vigorous plants with attractive roots. Its table 

 quality, however, is disappointing. A cross was made, therefore, between 

 Hutchinson and Morse's Bunching, a kind similar to the high quality Nantes 

 variety. It was planned to select from this cros^ a variety having roots of 

 long attractive shape and high table quality. The carrot has a composite 

 flower consisting of many small florets. Manipulation of such small flowers 

 by hand methods in controlled breeding work is difficult, though copious 

 crops of carrot seed result in the open field as a result of insect visitations 

 of the flowers. Hence, resort was made to insects for pollination of flowers 

 of carrots forced into bloom within the greenhouse during the winter. 

 Several plants of the two varieties to be crossed were enclosed within a 

 screened cage and houseflies"* were released in the cage for a pollinating 

 agent. The seeds from each plant were saved separately. When each lot of 

 seed was grown in a single row in the field as a progeny test, the Fj -hybrid 

 plants could be distinguished by their exceptional vigor and certain domi- 

 nant characteristics. Seed of the F^ -plants was raised in the greenhouse 

 during the winter. The procedure for this has alreadv been described. Thus 

 a second generation could be grown in the field the following summer. 

 Carrots of the desired size, shape, and rich orange color inside the root 

 were selected from the variable second generation. Each carrot was cut to 

 expose a cross section of the interior of the root before a final selection 

 was made for seed production. Usually eight or ten such selected carrots 

 were allowed to mass pollinate within a single cage. This has helped to 

 maintain vigorous lines of carrots down through the several generations 

 necessarv to establish the new^ varietv now called Durham Carrot. 



The Durham carrot (at left) is a medium long, high-quality variety which is 

 adapted to bunching or packaging. At the right is the cage in the greenhouse 

 where the carrots are grown for seed. Pollination is provided by house flies. 



* The Entomology Department rears houseflies for u?e in testing the effectiveness 

 of insecticides. Repeatedly, the entomologists have furnished flies for pollination of 

 vegetables. 



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