. Cyclopedia of American horticulture, comprising suggestions for cultivation of horticultural plants, descriptions of the species of fruits, vegetables, flowers and ornamental plants sold in the United States and Canada, together with geographical and biographical sketches, and a synopsis of the vegetable kingdom . fruit on numeroustrees, and then take seed for planting from that treewhich by the examination of many fruits is found toshow the most decided general tendency toward seed-lessness. Limitations of Selection. —Selection is by many horti-culturists considered to have been the most im
. Cyclopedia of American horticulture, comprising suggestions for cultivation of horticultural plants, descriptions of the species of fruits, vegetables, flowers and ornamental plants sold in the United States and Canada, together with geographical and biographical sketches, and a synopsis of the vegetable kingdom . fruit on numeroustrees, and then take seed for planting from that treewhich by the examination of many fruits is found toshow the most decided general tendency toward seed-lessness. Limitations of Selection. —Selection is by many horti-culturists considered to have been the most importantfactor in the development of our cultivated plants, andsome go so far as to assert that all other factors areof minor importance. Both crossing and selection,however, have their definite and distinct places in anyrational system of plant-breeding. When used alone inthe improvement of plants, selection depends upon theadding up of small, insignificant variations throughmany generations, which in the end may possiblyresult in marvelous differences; but by this method thebreeder has no way to force the change, and must besatisfied with slight variation and long-continued selec-tion. When marked changes and new creations aredesired it is to crossing or to chance sports that at-tention must be 1842. Aquilegia flowers, illustrating the process ofemasculation. a, mature bud showing stage which should be selectedfor emasculation; 6, similar bud with the tips of thecorolla pried apart and the stamens removed; c, a budopened naturally, too old to operate on; d, a bud of thestage shown in a and 6, with corolla removed to showthe internal organs: e, a bud the same as in d, but withthe stamens removed; f, the same as e, but older, at theage when pollination normally takes place ; g, pistilshortly after fecundation, the remnants of the stamenshaving fallen away. Improvement by Means of Crossing.—Aside fromselection, crossing has played the most important rolein the form
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyo, bookyear1906
