36 TOBACCO BREEDING. 



than the suckering plant, which condition is usually true in all such- 

 cases. 



The production of many large suckers is usually correlated with 

 the development of few. heavy, dark, and usually narrow, pointed 

 leaves. This condition is explained on the ground that the large 

 sucker branches take from the plants the elements of plant food 

 which otherwise would be utilized in the development of many 

 broad, round leaves. The possibility of securing nonsuckering types 

 of tobacco was suggested in the course of a series of experiments in 

 the improvement of cigar-wrapper tobaccos. In the selection of seed 

 plants great care was exercised to pick out those bearing the largest 

 number of rounded leaves with fine veins. In the course of the 

 study of the progeny of these plants it was observed that few suckers 

 were produced by the most desirable types of plants. The continued 

 observations on this subject have confirmed the conclusions that 

 there is a correlation between the number, shape, and character of 

 the leaves borne by individual plants and the number and size of 

 suckers produced by these plants. 



The number and size of the suckers produced by the plants in all 

 tobaccos is an important practical problem from several standpoints. 

 Owing to the dwarfing and otherwise injurious effect of the suckers 

 it is necessary to remove them by breaking them off. or to " sucker " 

 the plants, as the process is commonly called. There is great danger 

 of breaking, tearing, or injuring the leaves during the suckering 

 process, and this causes much loss in cigar-wrapper varieties, as the 

 injured cigar-wrapper leaf is rendered practically worthless. A care- 

 less laborer frequently causes great loss to the grower during the 

 process of suckering the plants. Owing to the fact that the suckers 

 do not develop on all of the plants at the same time and consequently 

 can not all be removed at once, it is necessary to go over the field 

 several times during the season in order to remove all of them. 



The cost of suckering is one of the important items of expense in 

 the cultivation of tobacco. Therefore the production of nonsuckering 

 types is an economic problem of great importance, not only by 

 reason of the reduction in the cost of growing the crop, but from the 

 fact that the nonsuckering types usually produce a larger yield of a 

 more desirable quality of tobacco than the suckering types. 



It has been found possible to produce uniform strains of different 

 varieties of tobacco having but few and small >uckers by saving the 

 seed from nonsuckering plants under bag. As an illustration of the 

 possibility of the growers producing such types the experience of one 

 of the writers in the improvement of the Connecticut Broadleaf 

 tobacco may be cited. In these experiments desirable plants were 

 selected for seed in 1903. producing round leaves of fine, silky texture 



96 



