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PLANT GROWTH 



been described in scientific literature in recent years. It has 

 become an important field of study, and many attempts have 

 been made to increase the number of mutations. 



Two important commercial apple bud mutations (called 

 sports) appeared on trees of the Delicious variety; one was 

 called the Golden Delicious and another was the origin of 

 the Starking variety. Nursery men paid fancy prices for 

 these sports. These finds caused agricultural periodicals to 

 suggest careful search for bud sports. 



Fig. 23. Domesticated varieties derived from the wild cabbage, Brassica oleracea 

 (A) , a native of Europe. B is kale, Brassica oleracea acephala; C, kohlrabi, B. oleracea 

 caulo-rapa; D, Brussels sprouts, B. oleracea gemmifera; E, pointed-head cabbage, B. 

 oleracea capitata; F, round-head cabbage, B. oleracea capitata; G, cauliflower, B. 

 oleracea botrytis. (From Transeau et al., Textbook of Botany. By permission of 

 Harper Bros., 1940.) 



Fruits with commercial value have long lists of bud sport 

 varieties. Hundreds of varieties of bud sports of roses and 

 thousands of varieties of chrysanthemums have been de- 

 veloped. It must be remembered that these are the only 

 ones recorded in literature. Most people do not observe 

 their plants with the care necessary to detect differences, and 

 doubtless many have been observed but not recorded. With 

 the increased interest in the science of gardening we may 

 expect the number of reported bud sports of plants to be 

 amazing. Any unusual shape, size, color, or rate of growth 

 should be studied as a possible valuable bud sport. 



