アメリカアリタソウの春化処理

Abstract

American wormseed (Chenopodium ambrosioides L. var. anthelminticum (L.) A. GRAY) has medicinal use and is also a source of essential oil (chenopodium oil), 45-70 percent of which is ascaridole.American wormseed seeds (in fact, they are utricle), vernalized at four temperatures, 35°, 25°, 15° and 5° for 5 days respectively, were sowed on April 6, 1957, using as the control non-treated seeds.1) The germination, especially the germination rate, was greatly influenced by the vernalization: the 35°-treated group hardly germinated, the germination rate of the 25°-treated group was generally equal to the control. But those of the 15°-treated and of the 5°-treated group increased over 10 percent more than the germination rate of the control.2) To clarify the effect of the vernalization on the plant development we examined the flowering season. The 35°-treated group and the 25°-treated one flowered about 4 days earlier than the control, but the flowering of the 15°-treated one was not different from that of the control, and that of the 5°-treated one was a little later than that of the control. Therefore American wormseed seems to pass through its vernalization phase at comparatively high temperatures, from 25° to 35°.3) As to the yield of air dried seeds, there was no difference between the treated groups and the control, but the content of essential oil in seeds was greatly influenced by the vernalization: that of the 35°-treated group and the 25°-treated one increased several percent and the 15°-treated one more than 10 percent, but that of the 5°-treated one less than the control. As for the content of ascaridole in essential oil, there is no difference between the treated ones and the control. According to the experiment in 1955 on seeds that were vernalized at 15° for 10 days and for 20 days, the content of essential oil in seeds increased 26 percent in the 10-daytreated group and 11 percent in the 20-day-treated groups, as compared with the control.From these effects, American wormseed vernalized at 15°, especially for about 10 days results in an increase in the yield of essential oil and is useful in cultivation. And the temperature in the vernalization phase of plants is not only related to development, but also seems to have great influence upon the content of the active constituent.