1994 Volume 34 Issue 4 Pages 298-306
In the present work, we have developed a laboratory exercise suitable for teaching asexual reproduction in Japanese junior high schools. Twenty-three species of familiar flowering plants, all of which are wild herbaceous plants, were used. Leaves of these plants were cut near the base of their stalks from the stems or stems and roots of these plants were cut into pieces of about 1 cm in length.
These plant cuttings were placed on two layers of wet filter paper and kept in a plastic box for 10 days at 25°C under L : D=12 : 12 light regime. The light intensity of 2 klux was obtained from fluorescent lamps. In 14 species, adventitious buds or roots sprouted from some cuttings of these plants. Among the 14 species, the formation of adventitious buds and roots was observed well in both the stem and root segments of Rorippa indica (Brassicaceae). The formation of adventitious buds and roots was also observed in the stem segments of Oxalis corniculata (Oxalidaceae), Trifolium repens (Leguminosae), Achyranthes japonica (Amaranthaceae) and Pinellia ternata (Araceae).
Trials of the developed exercise in science classes were done at a junior high school located in Tokyo. Enough plant materials could be collected in the yard of the school. The experimental method of the exercise seemed to be easy for the junior high school students. The students could understand the result of the exercise and readily connected it to the asexual reproduction of the plants. Thus, the exercise developed in the present work is useful for teaching the asexual reproduction of higher plants at the junior high school level.
