Polygonatum odoratum (Miller) Druce var. pluriflorum (Miq.) Ohwi (Convallariaceae)

The life-history characteristics of Polygonatum odoratum (Miller) Druce var. pluriflorum (Miq.) Ohwi (Convallariaceae) are described. This is a polycarpic perennial that occurs in Honshu, Shikoku and Kyushu in Japan, extending further to the Korean Peninsula and China. Polygonatum odoratum var. pluriflorum is a late starter in spring, its shoots sprouting in late April to early May, while the upper canopy layer is gradually expanding its foliage leaves and casting shade on the forest floor. Flowering starts in mid-May right after the aerial shoots sprout; flowers are axillary, with 0.8 to 2 cm pedicels; 1 to 2 flowers, white, greenish near the tip and 17-19 mm long, hang from several portions of the inflorescences of the angled stems, which attain 30-60 cm in height. This is a typical insect-pollinated plant, and white tubular flowers with a large nectary hang down from the inflorescence. Flowering occurs sequentially from bottom to top. The numbers of ovules and pollen grains per flower were 14-18 and 42 000-90 000, respectively, and pollen/ovule (P/O) ratios of 3000/5300 indicate that this is an outbreeding species. There is a tendency for the P/O ratios to decrease gradually in later flowering upper flowers within an inflorescence. The fruit set within an inflorescence also showed a similar tendency, that is, approximately 55.2% in lower flowers, 35.8% in middle flowers and 17.3% in upper flowers. As was reported in var. odoratum, there may be resource competition among flowers within an inflorescence.