[Microscopic identification of tibetan medicinal herb "Songdi" (Saxifraga umbellulata var pectinata)].

OBJECTIVE: To establish a method of microscopic identification of Tibetan medicinal herb " Songdi" (Saxifraga umbellulata var. pectinata). METHOD: The different characteristics and microscopic identification of 4 species of Songdi were compared, including the main variety (Saxifraga umbellulata var. pectinata ) and approximate varieties (S. unguiculata, S. przewalskii and S. tanguTi,) were studied and compared. RESULT: The botanical anatomy characteristics of Saxifraga umbellulata var. pectinata (including roots, stems, leaves, flowers, stalks and fruits) have been measured. The methods for powder identifications and transverse section of stems root and leaves of four species of Songdi were established. CONCLUSION: Four species of Songdi can be identified by the growth pattern of basal leaves, type of hair, type of inflorescence, number of flowers, proportion of tissue structures in stem, form of pollen grains.

Effect of temperature on the progamic phase in high-mountain plants.

Progamic processes are particularly temperature-sensitive and, in lowland plants, are usually drastically reduced below 10 °C and above 30 °C. Little is known about how effectively sexual processes of mountain plants function under the large temperature fluctuations at higher altitudes. The present study examines duration and thermal thresholds for progamic processes in six common plant species (Cerastium uniflorum, Gentianella germanica, Ranunculus alpestris, R. glacialis, Saxifraga bryoides, S. caesia) from different altitudinal zones in the European Alps. Whole plants were collected from natural sites shortly before anthesis and kept in a climate chamber until further processing. Flowers with receptive stigmas were hand-pollinated with allopollen and exposed to controlled temperatures between -2 and 40 °C. Pollen performance (adhesion to the stigma, germination, tube growth, fertilisation) was quantitatively analysed, using the aniline blue fluorescence method. Pollen adhesion was possible from -2 to 40 °C. Pollen germination and tube growth occurred from around 0 to 35 °C in most species. Fertilisation was observed from 5 to 30-32 °C (0-35 °C in G. germanica). The progamic phase was shortest in G. germanica (2 h at 30 °C, 12 h at 5 °C, 24 h at 0 °C), followed by R. glacialis (first fertilisation after 2 h at 30 °C, 18 h at 5 °C). In the remaining species, first fertilisation usually occurred after 4-6 h at 30 °C and after 24-30 h at 5 °C. Thus, mountain plants show remarkably flexible pollen performance over a wide temperature range and a short progamic phase, which may be essential for successful reproduction in the stochastic high-mountain climate.

[Pharmacognostic identification of Rodersia aesculifolia].

OBJECTIVE: To establish pharmacognostical methods of Rodersia aesculifolia. METHODS: Macroscopical, microscopic and physicochemical identification were used to authenticate this crude drug, and the identification characteristics were studied. RESULTS: There were some palea on the rhizoma superior extremity and some white flare dot on transverse section. Vascular bundle formed into interval circularity in rhizoma transverse section, and some small atypia bundle appeared in lateral of core. Xylem of root was tetrarch. A lot of starch grain and acicular cyrstal were observed in parenchyma cell. Brown cell was present as single or several linked. CONCLUSION: These characteristics can be used as identification basis for Rodersia aesulifolia Batal.