398 GENETICS IN RELATION TO AGRICULTURE 
of seed potatoes. It is transmitted through the seed. (4) It is doubtful if any 
method of seed selection will prevent the “running out’ of seed potatoes under 
certain conditions.” 
Other Crops in Which Bud Selection May Apply.—It is claimed that 
many desirable varieties of roses, carnations, chrysanthemums, violets 
and other plants which are cultivated for their flowers originated as 
bud sports. The best florists are very critical regarding the character- 
istics of their stock and sports are soon discovered. The importance of 
propagating from typical, healthy plants is generally appreciated. 
Many of the roses used for forcing winter blooms produce two types of 
shoots which are known to the horticulturist as blind and flowering 
wood. For some years the Bureau of Plant Industry conducted ex- 
periments on the selection of buds from the two types of shoots, but it 
became apparent that the diversity among individual plants in regard 
to their flowering habits, whether propagated from blind or from flowering 
wood, was greater than the diversity between the progeny of flowering 
wood plants as compared with the progeny of blind wood plants. Asa 
result of fertilizer experiments with the variety, My Maryland, Blake 
inferred that there was a real basis for production of improved strains 
by bud selection. But he points out that it would require time and much 
care in selection and that the average florist can hardly attempt to do 
more than to note the relative vigor of his plants at various stages and 
propagate from the best producers that are not especially favored by 
particular environmental conditions. 
The strawberry is so important commercially and comes into bearing 
so soon when propagated from offsets that if bud selection were effective 
in producing improved strains it would be of tremendous practical value. 
But the results of experiments indicate that the individual differences so 
frequently observed in strawberry plants are merely modifications. Whit- 
ten reports that bud selection of strawberry plants during a period of 
15 years has given no gain in the total productiveness of the plots 
which originated from high-productive plants over the plots which 
originated from low-productive plants of the same variety. The experi- 
ment began by selecting six plants that yielded four times the amount of 
fruit of six low-producing plants all of the Aroma variety. Each 
succeeding year selections in the high-yielding plot were made from the 
highest plants and in the low-yielding plot from lowest-yielding plants. 
It is possible that in some varieties of strawberries bud mutations occur 
more frequently than in others. But in order to find a high-yielding 
plant whose high-producing character would be maintained among its 
vegetative offspring it would probably be necessary to test hundreds of 
individual high-producing plants. Hybridization offers much greater 
promise in the production of high-yielding strains of strawberries. 
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