[Analysis of reproductive ecological factors of endangered Rhodiola gannanica.] / ç”˜å—çº¢æ™¯å¤©æ¿’å±çš„ç”Ÿæ®–ç”Ÿæ€å­¦å› ç´ åˆ†æž.

To find effective ways for protecting and recovering an endangered species Rhodiola gannanica in Gannan, an important distribution region of this species in the eastern Tibetan Plateau of China, the breeding system, reproductive process, flowering phenological characteristics and other reproductive controlling factors were investigated. The results showed that there was a unique breeding system in R. gannanica, which was dioecious, and male flowers were also bisexual plants in the early stage of flower bud differentiation. While the sac of pistil was aborted in a certain stage with the development of flowers, the bisexual plants only played the role of males' functions. The outcrossing reproduction was observed, the pollination mode was mainly by wind, and the population flowering occurred in the season with abundant precipitation and high temperature. The bud satge appeared in early June, the florescence was in mid-June, and the flourishing florescence was in early July. The flo-wering duration of R. fastigiata was about 36 d, and the fruit ripening began in late August. The flo-wering time and the flowering duration of the bisexual plants were earlier than female plants. Due to the low pollination rate of the female plants, the buds and ovules were damaged and the 1-3 years young plants barely got flowering and fruiting, the rate of flowering and fruiting of the community only reached 11.0% and the rate of seed natural propagation was low (about 2.0%). 20.0%-25.1% buds of female plants were damaged from bud to flowering stages. 51.1%-65.0% flowers were aborted from flowering to fruiting stages. Only 10.1%-21.0% of ovules developed into seeds. The seed production of per female plant was 158.1, seed germination rate was 81.5% under artificial conditions, and seedling survival rate reached 36.0% in the first year. Our results revealed that seed quality was not the key ecological factor, while it was the pollen limitation, low seed production and the survival rate of seedling that resulted in the reproductive success and species endangered situation.

Approaches of Rhodiola kirilowii and Rhodiola rosea field cultivation in Poland and their potential health benefits.

Numerous researches have been carried out on plants of the Rhodiola species, especially Rhodiola kirilowii (Regel) Maxim. and Rhodiola rosea. Various compounds have been reported to be isolated from R. kirilowii and R. rosea, including cyanogenic glycosides, monoterpene alcohols and their glycosides, aryl glycosides, phenylethanoids, phenylpropanoids and their glycosides (salidroside and rosavins respectively), as well as flavonoids, flavonlignans, proanthocyanidins and gallic acid derivatives and the latter have free radical scavenging capacity. The benefits claimed for Rhodiola include adapogenic, neuroprotective, anti-depresive anti-tumour and cardioprotective activities. Currently, the adaptogenic activity of Rhodiola compounds are properties evaluated mainly in human clinical trials. The mechanism of the action of Rhodiola extracts include affecting the levels of cortisol and NO by interactions with glucocorticoid receptors directly or via the c-Jun N-terminal protein kinase (JNK) pathway. However, the natural populations of R. rosea in Poland are threatened; therefore, the cultivation of R. rosea and alternative species R. kirilowii might be a possible solution for producing these kinds of plants in Poland in sufficient quantities and quality for pharmaceutical purposes. Lack of proven interaction with other drugs and no confirmed adverse effects during clinical trials encourages further investigation. These herb preparations ought to be studied extensively to establish their position as potential drugs for a variety of diseases.

Improved mass multiplication of Rhodiola crenulata shoots using temporary immersion bioreactor with forced ventilation.

A temporary immersion bioreactor system was found to be suitable for mass shoot proliferation of Rhodiola crenulata. The shoot multiplication ratio and hyperhydration rate reached 46.8 and 35.4%, respectively, at a temporary immersion cycle of 3-min immersion every 300 min. Forced ventilation was employed in the temporary immersion bioreactor culture in order to decrease the hyperhydration rate, improve shoot quality and enhance the multiplication ratio. The highest multiplication ratio of 55.7 was obtained under a temporary immersion cycle of 3-min immersion every 180 min with the forced ventilation at an air flow rate of 40 l/h, and the hyperhydration rate was reduced to 26.1%. Forced ventilation also improved the subsequent elongation and rooting rate of these proliferated shoots, and the shoot cultures from the temporary immersion bioreactor formed complete plantlets when subcultured onto a rooting medium containing 5 µmol/l indole-3-acetic acid.

[Effects of different light and GA3 on the germination and seedling growth of Rhodiola sachalinensis].

OBJECTIVE: To improve germination rate and research the seed germination character of Rhodiola sachalinensis. METHODS: Made seed germinated under water or with moisture, at light or dark condition, effects of 6 different light qualities (black, white, blue, green, red and far red light) illumination on seed germination were studied. The seedling growth at different temperature were studied as well. RESULTS: The results indicated that light was required for Rhodiola sachalinensis seeds germinate, 83.3% germination rate at light and soaking in watercondition; Seed germination were improved to 84%, 70.7% and 52.0% respectively in white, red and green light quality illumination, the germination rate reached 84% after 9 h of white light illumination. Germination rate were 80% after 100 mg/L GA3 treatment for 3 h under dark condition. 20 degrees C was the optimal temperature for Rhodiola sachalinensis seedling growth, under with the plant height, fresh weight and dry weight of plant were the best. Seedling growth rate and the dry weight increased obviously at 35 d and 50 d. CONCLUSION: The experiment definited the best condition for Rhodiola sachalinensis seed germination and seedling growth, supplied basic data for large scale planting Rhodiola sachalinensis using seed propagation technology.

[Tissue culture and plant regeneration of Rhodiola henryi].

OBJECTIVE: To study the tissue culture and plant regeneration technologies and optimizing propagation system in vitro of Rhodiola henryi. METHOD: Orthogonal experiment designs were used in the study of Rh. henryi callus induction, shoot formation and rooting, and the data were analyzed by range analysis and variance analysis. RESULT: The optimal media to induce multiple callus from leaves were MS supplemented with 2,4-D 1.5 mg x L(-1) and 6-BA 0.5 mg x L the effect of the three factors was in sequence of explants > 2,4-D > 6-BA; The optimal media to induce multiple buds from stems were MS supplemented with 6-BA 1.5 mg x L\/1-1 NAA >6-BA; Plantlets were rooted on 1/2MS supplemented with IBA 1.0 mg x L-1, and rooting rate reached to 90% or more and transplant survival rate of plantlet reached 98% or more. CONCLUSION: An efficient system for tissue culture and plant regeneration of Rh. henryi was initially established.

High yield production of salidroside in the suspension culture of Rhodiola sachalinensis.

Salidroside has been identified as the most potent ingredient of the Chinese medicine herb, Rhodiola sachalinensis. Since the natural supply of this herb is rapidly decreasing, we established a compact callus aggregate (CCA) strain and culturing system for high yield salidroside production. Several callus strains induced from the explants originated from root, stem, leaf and cotyledon of R. sachalinensis were established and screened for rapid growth rate, high salidroside content and easy propagation in suspension culture condition. The CCA strain was established from a callus strain initiated from the cotyledon. The kinetics of dry weight accumulation and cellular salidroside content in various culture conditions for the strain was determined. For high salidroside production, the optimal inoculum amount was 10% and the optimal concentration for 6-benzylaminopurine and indole-3-butyric acid added in the liquid medium was 5 and 2.5 mg l-1, respectively. The acidic culture medium and a faster shaking speed favored the salidroside accumulation. The addition of 2,4-D, in the liquid MS medium and the utilization of L-tyrosol for chemical feeding enhanced salidroside production. Using a proper combination of culture condition and treatment, salidroside accumulation could reach 57.72 mg g-1 dry weight, that was 5-10-fold higher than that detected in field-grown plants. The corresponding salidroside yield was 555.13 mg l-1, a level suitable for cost effective commercial production to compensate the natural resource shortage of R. sachalinensis.