BUD VARIATION IN LEMONS 



Tree Grown from a Single Bud Will Produce Several Types of Fruit, Which Can 



In Turn be Propagated — Importance of Careful Selection of Budwood 



for Propagation — Profits of Lemon Industry Can be 



Much Increased by Bud Selection.^ 



A. D. Shamel 

 Office of Horticulture and Pomology, Bureau of Plant Industry, U. S. Department o f 



Agriculture; Riverside, Cal. 



THE study of the remarkable bud 

 variations of the Washington 

 navel orange in California or- 

 chards^ was begun by the vi^riter 

 in 1909. This investigation led to a 

 similar study of the bud variations of 

 other citrus varieties. In 1911, at 

 Corona, Cal., a systematic study of 

 the bud variations of the Eureka lemon 

 (Citrus limonum Risso) was begini by 

 the writer and his associates. Later, 

 these studies were extended to include 

 the variations of the Lisbon and Villa- 

 franca varieties. The performance rec- 

 ords and observations of trees of these 

 three varieties of lemons have all been 

 secured in citrus orchards near Corona. 

 Commercial performance records have 

 been secured by cooperators in several 

 lemon orchards in the different citrus 

 districts of California, so that at the 

 present time there is available for study 

 a large amount of reliable data concern- 

 ing these varieties and their behavior. 

 The individual lemon tree perform- 

 ance records are now being prepared 

 for publication by the Bureau of Plant 

 Industry of the U. S. Department of 

 Agriculture. Until this publication has 

 been completed, we will be unable to 

 present the performance records, notes 

 or other data for use elsewhere. For 

 this reason I shall not attempt in this 

 paper to give any details of the results 

 of the investigational work, and will 



only discuss some general observations 

 in the hope of emphasizing the desira- 

 bility of further similar systematic 

 investigations of bud variations in 

 citrus fruits grown in other regions, 

 and in all other plants propagated 

 vegetatively. 



OBJECT OF STUDY 



The object of these studies is to 

 determine the extent and frequency of 

 bud variations in lemon varieties, the 

 comparative commercial value of the 

 various strains arising from bud varia- 

 tions, the development of methods for 

 isolating the best strains and controlling 

 variability in them through bud selection . 



Before attempting a scientific study 

 of the causes of bud variability, it was 

 decided to determine definitely the 

 actual conditions in established orchards 

 with respect to bud variation. This 

 study was begun without any prejudice, 

 one way or another, and with little or 

 no knowledge of the phenomena of bud 

 variation in plants. 



The work of the writer, previous to 

 taking up these studies, was confined to 

 studies of plants propagated from seed. 

 In order to prevent any possibility of 

 bias in the study of the variability of 

 plants propagated vegetatively, no at- 

 tempt was made to review the small 

 amount of available literature on this 

 subject. Our observations and con- 



^ Read by title at the thirteenth annual meeting of the American Genetic Association, New 

 York City, December 27, 1916. 



2 See Shamel, A. D., Bud Variation. Journal of Hereditv, Vol. vii, pp. 82-87, February, 

 1916; Washington Navel Orange, ibid.. Vol. vi, pp. 435-445, October, 1915. See also Improve- 

 ment of CaHfornia Orange Groves, Journtal of Heredity, Vol. vii, p. 493, November, 1916, 

 and Cooperation in Production of California Graoefruit, ibid., Vol. vii, pp. 524-527, November, 

 1916. 



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