落葉広葉樹林の林床へのエゾエンゴサク種子の播種または塊茎の移植

Abstract

Large and aesthetic populations of native plant species such as Erythronium japonicum, Corydalis ambigua, Gagea lutea, Cardiocrinum cordatum var. glehnii, and Trillium camschatcense impart a beautiful color to the floors of broad-leaved deciduous forests in Hokkaido, Japan. In this study, we revealed that the effects of seed sowing, tuber age, and transplanting depth of tubers in Corydalis ambigua on the germination and growth of tubers in the following year. In May, immediately after the seed collection, seeds were sown both in pots in the flame house and in the deciduous forest floor. Pots were watered adequately and the soil surface in the forest floor was well prepared. In the following spring, 66% of the seeds germinated in pots and 36% - 45% of the seeds germinated in the forest floor. Both the 1-year-old tubers and the 2-year-old tubers were transplanted at a depth of 2 cm or 8 cm in the autumn immediately after the root emerging from tubers, and then more than 89% of both tubers that were transplanted at a depth of 2 cm or 8 cm sprouted leaves in the following spring.Tubers transplanted at a depth of 8 cm tended to grow more than tubers transplanted at a depth of 2 cm. Dry weight of 1-year-old tubers that experienced one growing season increased by 3 - 7 times to their initial dry weight,and by 3 - 5 times in the 2-year-old tubers. About 50% of the 2-year-old tubers transplanted in autumn flowered in the following spring and have average of about 3 flowers. However no 1-year-old tuber flowered in the next year.