@article{oai:kindai.repo.nii.ac.jp:00005005, author = {杉野, 守 and 芦田, 馨}, issue = {20}, journal = {近畿大学農学部紀要, Memoirs of the Faculty of Agriculture of Kinki University}, month = {Jan}, note = {Beggar-ticks is a non-native weed distributed widely in Japan. The plants within one field population flower simultaneously in the autumn. They initiate flower primordia in the latter part of August and flower toward the end of September in the Osaka district. We studied the flowering responces of plants to the length of the day. Results showed that beggar-ticks is a qualitative short-day plant. When young plants were exposed to a short photoperiod for more than three or four days, even cotyledonary seedlings initiated flower primordia that were visible 10 to 20 days after the first short day, but they remained vegetative under continuous long days. The critical daylength for short days seemed to be about fourteen hours. When the number of short days was insufficient, flowering did not occur (with one to two or three short days). The percentage of plants that initiated flowers was low and their flowering stage was not advanced when long days followed short-day treatment of less than ten to twenty days. A long day intercalated into the inductive short days sometimes accelerated the flowering, suggesting the formation of some stimulative precursor or the other substance during the long day too short to inhibit flowering., application/pdf}, pages = {13--23}, title = {雑草の発育生理学的研究(第2報) : アメリカセンダングサの短日および長日に対する花成反応}, year = {1987}, yomi = {スギノ, マモル and アシダ, カオル} }