Biology of Geranium sibiricum (Geraniaceae) Flowering and Fruiting in the Novosibirsk Region

The flowering and fruiting of valuable medicinal plant Geranium sibiricum L. in the birch-pine forest in the Novosibirsk Region was studied. Synflorescence is compound dichasium. The period of flowering of one flower is 1—1.5 days. The continuous growth of the axes of generative shoots determines a long period of flowering and fruiting up to 2—2.5 months, up to the end of the seasonal vegetation of plants. G. sibiricum rarely produces intermediate flowers of a smaller size than bisexual ones, which, along with fertile stamens, have staminodes. The fruit of G. sibiricum is a capsule that forms within 20—25 days. An average of 3.4 ± 0.1 seeds ripen in one fruit. The real seed productivity of G. sibiricum is relatively high and averages 384.5 ± 50.56 seeds per plant. The 100-seed weight is 0.192 ± 0.003 g. Fruits and seeds are formed by 86 ± 1.9 % flowers per plant. The comparatively high seed productivity of G. sibiricum allows plants to successfully colonize disturbed habitats.