Wood anatomy of representatives of the Rosaceae from northern Siberia. 1. Spiraeoideae and Maloideae.

摘要

Descriptions are given of the wood anatomy of six species belonging to two genera of the Spiraeoideae (Sorbaria pallasii, S. sorbifolia, Spiraea betulifolia, S. dahurica, S. media, S. salicifolia) and four species belonging to four genera of the Maloideae (Cotoneaster melanocarpus, Malus pallasiana, Sorbocotoneaster pozdnjakovii, Sorbus sibirica) from the subarctic zone of Siberia. Sorbaria pallasii, Sorbocotoneaster pozdnjakovii, Spiraea betulifolia and S. dahurica have been characterized anatomically for the first time. The anatomical features of Malus pallasiana and Sorbocotoneaster pozdnjakovii show the lowest variability and those of Spiraea dahurica the highest. In both subfamiliers the proportion of solitary vessels shows the lowest variability, and the ray height shows the highest one. Wood anatomical features of north-Siberian Sorbaria and Spiraea are similar to the species from warmer regions. However, they have some distinctions. For example, the subarctic Sorbaria has more narrow multiseriate rays and septate fibres in addition to non-septate ones; in Spiraea media tyloses are formed in the vessels; S. media and S. salicifolia have helical thickening in the vessels and S. salicifolia has helical thickenings in the fibre-tracheids, Cotoneaster melanocarpus has higher multiseriate rays and scalariform perforation plates; Malus pallasiana has shorter vessel elements and narrower vessels; Sorbus sibirica also has shorter vessel elements and less frequent vessels. These differences are thought to be the result of ecological adaptation of the xylem.