著者

鶴内 孝之 古屋 忠彦 村山 祥子 島野 至 松本 重男

出版者

日本雑草学会

雑誌

雑草研究 (ISSN:0372798X)

巻号頁・発行日

vol.33, no.3, pp.185-190, 1988-10-31

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1 . lvyleaf speedwell plants were grown in four air conditioning rooms at constant temperatures under natural day length, from 1982 to 1983. In the 15℃ room, they formed a pair of opposite leaves on each of the lower 4 to 6 nodes of the stems, and then an alternate leaf and a flower on each of the upper nodes. In the 20℃ room, they formed opposite leaves on the lower 5 to 7 nodes, and then an alternate leaf and a flower, but fruiting was not prominent. In the 25℃ room, they developed only opposite leaves without a transition to alternate leaf arrangement. In addition, vegetative growth continued and no flowers was produced (Fig. 2) . In the 30℃ room, they did not grow and died within 1 or 2 weeks. 2 . Germinating seeds of ivyleaf speedwell were treated in a 4℃ incubator for 8 or 26 days, and young green plants of ivyleaf speedwell and birdseye speedwell were grown in at air conditioning box at 10℃ under diffused sunlight for 16 or 28 days, from 1984 to 1985 (Table 1) . Thereafter the materials were transferred to the 15, 20 and 25℃ rooms. The exposure of the germinating seeds to 4℃ and of the green young plants to 10℃ promoted the transition from opposite to alternate leaf arrangement, flowering and fruiting. The most remarkable results were as follows : the ivyleaf speedwell plants did not flower in the 25℃ room (Fig. 2), but the exposure to the low temperatures of 4℃ and 10℃ for 26 (VL) or 28 (GL) days, promoted the transition from an opposite to an alternate leaf arrangement, as well as flowering and in some cases fruiting (Table 2) .