FIELD RECORDS OF BREEDING WORK. 47 



ters from parent plants to progeny is shown in Plate VIII. A de- 

 tailed estimate of the plants in the field in respect to these charac- 

 ters is valuable only as a guide to the selection of the best type of 

 plants for a particular or a pedigree record, but must always be of 

 secondary importance to the judgment of the grower as regards the 

 general type of the plants and their adaptability for successful and 

 profitable production. 



In cigar-filler, smoking, and other varieties an intelligent selection 

 can only be made by the study of the cured and fermented leaves. 

 In this case it is necessary to save of plants that show in the field the 

 general physical characteristics desired several times the number that 

 will be necessary for seed. The leaves of these plants must be 

 primed and kept separate, properly labeled, hung in the curing shed 

 with the remainder of the crop so as to get normal curing conditions, 

 and carried thru the processes of fermentation with the bulk of the 

 crop. After the fermentation or sweating process has been com- 

 pleted, the samples from the individual plants can be tested, the seed 

 from the poor plants discarded, and the seed from the best plants 

 saved for planting. A description of the apparatus which has been 

 devised in the Office of Plant Breeding Investigations for testing the 

 burn or combustibility of cigar wrappers and for assisting in -the 

 comparison of the quality of cigar-filler and smoking tobaccos has 

 been published, as previously stated. In the study of the samples 

 from the individual seed plants it is absolutely necessary that they 

 all be brought under uniform conditions of moisture, heat, and 

 other conditions affecting the character of the leaves before the tests 

 are made. Final tests must always be confirmed by the use- of the 

 tobacco in cigars, pipes, or by other means of consumption for which 

 the tobacco is adapted. 



RECORDS OF BREEDING WORK MADE IN THE FIELD. 



The form of record blank used in the breeding work of the writers, 

 together with the directions for note taking and definition of terms, is 

 given here for the benefit of those who may wish to carry on system- 

 atic breeding work and keep a pedigree record of the parent plants 

 and their progeny. This plan of record keeping is being constantly 

 revised as the knowledge on the subject increases, but up to the pres- 

 ent time the plan described has been found to be very useful and 

 valuable, covering the most important characters and points neces- 

 sary for an adequate record. The plants finally selected for seed are 

 usually given a number for identification, this number being written 

 on a small, strong tag attached to the top of the plant below the paper 

 bag with a short piece of flexible wire. 



96 



