SINGLE-GERM BEET SEED 



Sugar Beet Is Being Made to Produce Single-germ Seeds Instead of Multiple-germ 

 Seed Balls — Labor Thus Saved Will Mean Gain of Several 

 Million Dollars Annually to Industry. 



C. 0. TOWNSEND 



Bureau of Plant Industry, U. S. Department of Agriculture, Washington, D. C. 



THE effort to produce a strain 

 of sugar beets that will bear 

 only separate seed germs, in- 

 stead of the seedballs con- 

 taining several germs, which ordinarily 

 characterize the sugar beet, arose from 

 a desire to reduce the cost of producing 

 sugar beets and beet-sugar. 



The term "seed ball," as applied to 

 beet seeds, implies a combination of 

 seeds into a mass having a more or 

 less rounded appearance. Each germ 

 arises from a single flower, and when 

 they are in clusters of two or more, 

 as is usually the case, a multiple-germ 

 seed arises; whereas if the flower stands 

 by itself on the stem, a single-germ 

 seed results. If two or more single 

 flowers stand very close together but 

 do not arise from the same point as in 

 the case of the flower clusters, each will 

 produce a single-germ seed. Even if 

 the flowers are so close together that 

 the seeds slightly adhere in the process 

 of development, they are easily sepa- 

 rated and readily distinguished as 

 single-germ seeds. It appears, there- 

 fore, that the arrangement and distri- 

 bution of the flowers on the seed stalk 

 determine whether the seeds are to be 

 single-germ seeds or whether they are 

 to be parts of multiple-seed balls. One 

 can determine in practically all cases, 

 even before the flower and buds are open, 

 whether they will produce single-germ 

 seeds or whether they will be parts of a 

 multiple-seed ball. 



More than 95 per cent, of the beet 

 seed of commerce is composed of 

 multiple-germ seed balls, the germs of 

 which are so closely welded together by 

 nature that they cannot by any known 

 means be separated without injury to the 



germ. In other words, less than 5 per 

 cent, of the seed balls of commercial beet 

 seed consist of a single germ. The 

 number of germs in the remaining 95 per 

 cent, or more of seed balls varies from two 

 to seven germs per ball. Hence the 

 mmiber of germs produced normally as 

 single-germs, that is, not welded into 

 combination with other germs, does not 

 exceed 1 per cent, of the total number of 

 germs produced by any commercial 

 seed-producing plant that has come 

 under the observation of the writer. 



METHOD OF PROCEDURE 



The fact that almost every beet 

 seed plant that matures seed produces 

 a few one-germ seeds shows that we 

 did not create anything new by our 

 work, despite a popular belief to the 

 contrary. We simply took advantage of 

 a tendency to produce single germs, 

 and selected with a view to getting an 

 increase in this tendency. Our goal is 

 the production of a strain of sugar beets 

 which will yield only one-germ seeds. 



The principal value of such a strain 

 lies in the economy of labor it wordd 

 make possible. It is an established 

 fact that the best results in beet growing 

 are produced when each beet plant 

 stands alone and 8 inches or more from 

 every other beet plant. Remembering 

 the construction or make-up of com- 

 mercial beet seed, it is apparent that 

 the only way to have each beet stand 

 by itself, so long as multiple-germ seed 

 balls are planted, is to pull out by hand 

 all beets but one at regular intervals in 

 row. This is called hand thinning and 

 is the most expensive and laborious 

 single operation in sugar beet growing, 

 costing from $5 to $8 per acre, or 



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