. Day length and crop yields. Plants; Crop yields; Plant photoperiodism. Leaf fall of the tuliptree and many others may be delayed when the photoperiod is long. profitable production. New and more specifically adapted varieties of soybeans are constantly being selected, so increasing acreages of this very important crop are being grown more economically through- out wider and wider areas. Recent experiments to develop sugar-beet seed furnish one of the most striking examples of the possibilities of securing newer and better varieties of a crop that is very sensitive in its responses to photo-
. Day length and crop yields. Plants; Crop yields; Plant photoperiodism. Leaf fall of the tuliptree and many others may be delayed when the photoperiod is long. profitable production. New and more specifically adapted varieties of soybeans are constantly being selected, so increasing acreages of this very important crop are being grown more economically through- out wider and wider areas. Recent experiments to develop sugar-beet seed furnish one of the most striking examples of the possibilities of securing newer and better varieties of a crop that is very sensitive in its responses to photo- period and temperature. Only a few years ago the United States imported from Europe nearly all the sugar-beet seed needed. While developing strains of sugar beets resistant to curly top it became necessary to multiply as rapidly as possible the stocks of seed within the United States. Previous experience in the southwestern United States indicated that field plantings made in late summer or early fall would success- fully overwinter and produce seed. This method of production depends in part upon exposure of the plants during winter months to moderately low temperatures. This exposure does not injure the plants, but it preconditions them so that they will develop seed the following summer. Such a procedure eliminates many labor-consum- ing operations characteristic of the European method and results in the efficient production of profitable yields of seed. On the basis of the knowledge that the production of sugar-beet seed is favored by long photoperiods, especially at certain tempera- tures or after a rather short exposure to relatively low temperatures, it has been possible to select localities that are much better suited to 12. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Parker, M. W. (Marion Wesley)
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Keywords: ., bookcentury1900, bookpublisherwashingtondcusd, booksubjectplants
