Variability of metric and qualitative traits of Nitraria species in relation to ecological and climatic conditions of Siberian habitats

Resumo

The metric traits of shrubs, leaves, seeds, and flower parts have been studied in 19 Siberian populations of Nitraria sibirica Pall. and N. schoberi L. According to the obtained data, N. schoberi is characterized by larger shrubs (150–179 cm in height), leaves (15–30 mm in length, 5.7–8.8 mm in width), and seeds (up to 10 mm in length) and has rather wide (~2.5 mm) corolla petals. The size of anthers exceeds that of N. sibirica 1.2–1.5 times. The height of N. sibirica shrubs does not exceed 80 cm; the length of lamina, seed, and petals of corolla is 8–10, 3.7–7.4, and ~3.5 mm, respectively; and the size of anthers is 0.5–1 mm. Irrespective of habitat conditions, the stability of metric traits typical for both species has been shown to be rather high. The only dependence on climatic parameters is observed for the height of N. sibirica, which forms creeping forms in continental regions, especially in the mountains of the Altai Republic. Vegetative organs (laminas and young shoots) of N. sibirica are always more pubescent than those of N. shoberi.