Laboratory of Plant Physiology, Department of Agriculture, Faculty of Agriculture, Kinki University
Laboratory of Plant Physiology, Department of Agriculture, Faculty of Agriculture, Kinki University
出版者 名前
近畿大学農学部
出版社 カナ
キンキ ダイガク ノウガクブ
出版社 ローマ字
Kinki daigaku nogakubu
出版年(from)
1987
雑誌名
近畿大学農学部紀要
雑誌名(英)
Memoirs of the Faculty of Agriculture of Kinki University
号
20
ページ
13 - 23
発行年
1987-01-01
ISSN
04538889
抄録
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.