VARIATION IN TOBACCO 



Change of Environment Seems not to Cause Breaking Up of Types — Crossing 



the Only Means of Producing New Types For Commercial Breeding, 



However, Both Heredity and Environment Must 



Be Taken into Consideration. 



H. K. Hayes 

 Plant Breeder, Connectieiit Ai^riciiltnral Experiment Station, New Haven, Conn. 



IN recent years many foreign ty]jes 

 of tobacco have been j^rown from 

 imported seed in the United States. 

 In most cases these have proved 

 very variable in their characters during 

 the early years of their development, 

 and this has led to a common belief 

 that a breaking up of type is caused by 

 the change of environment when seed 

 of southern tobacco is grown in the 

 north. 



Shamel', in a brief review of some of 

 the phases of tobacco breeding work, 

 says: "The writer believes that the 

 two cfiRcient means of inducing var- 

 iability as a source of new types are 

 of environment and crossing. 

 as the writer is concerned the 

 of environment — usually the 

 growing of southern seed in the north- 

 is the most effective means of inducing 

 variability." 



A recent article b\' Hasselbring- on 

 Cuban tobaccos gives a logical reason 

 f<jr the diversity of tyj^es which arc 

 found when Cuban seed is grown in the 

 United States. This writer shows that 

 there are many types of tobacco in 

 Cuba. As the seed is saved from suck- 

 ers which grow from the base of the old 

 roots and as these suckers do not show 

 the characteristics of the parent plants, 

 no attempts at seed selection have been 

 made. Furthermore, as the seedlings 

 are generally grown in the mountains 

 and sold to growers in all ])arts of the 



change 

 So far 

 chan<re 



island this diversity of types is con- 

 stantly maintained. 



Hasselbring also presents data on a 

 number of pure lines which were grown 

 botli in Cviba and in Michigan, and 

 shows that in these pure lines no break- 

 ing up of type occurred and that what- 

 ever modifications did apjjcar due to 

 the change of environment, appeared 

 alike in all of the plants of a given 

 strain. 



In 1908 the writer became interested 

 in the study of heredity in tobacco and 

 has had many opportunities to observe 

 the effects of environment on tobacco 

 characters. The results of these ob- 

 servations serve to corroborate the 

 belief that environment does not cause 

 a breaking u]) of type. 



(THAN VARIETIES USED. 



In 1910 an experiment was begun to 

 determine how many \'ears of se- 

 lection were necessary to develop 

 a t\'pe similar to the present Cuban 

 shade variety. During this season 

 about one hundred and fift>' ])lants 

 were grown at the Windsor Toliacco 

 Crowcrs' Corporation in Bloomfield 

 from seed sent from Cuba to the i:)lanta- 

 tion manager, J. B. Stewart. This 

 original seed was given a st'leelion ninn- 

 ber, \3. The variability tliis first year 

 was very large and only five or six of 

 the one hundred and fifty i)lants gave 

 ])romise of commercial \-aIue. Selfed 



'Shamel, .\. 1). Toliacco Brecdinj^ Amcr. Breeders Rc-jxnt, Vol. ft: 2M-115, 1")1(). 



^ HassclhririK', H. Tyix-sof Cuhan Tohhacco. Tlu' Botanical (lazcttf, Vol. 5.?; 1 l.vlift, 1012. 



40 



