De novo in vitro shoot morphogenesis from shoot tip-induced callus cultures of Gymnema sylvestre (Retz.) R. Br. ex Sm

BACKGROUND: Gymnema sylvestre is a medicinal woody perennial vine known for its sweetening properties and antidiabetic therapeutic uses in the modern and traditional medicines. Its over-exploitation for the therapeutic uses and to meet the demand of pharmaceutical industry in raw materials supply for the production of anti-diabetic drugs has led to considerable decline in its natural population. RESULTS: An efficient system of shoot bud sprouting from nodal segment explants and indirect plant regeneration from apical meristem-induced callus cultures of G. sylvestre have been developed on Murashige and Skoog (MS) medium amended with concentrations of cytokinins. Of the three growth regulators tested, N6-benzylaminopurine (BAP) was the most efficient and 2.0 mg L-1 gave the best shoot formation efficiency. This was followed by thidiazuron (TDZ) and kinetin (Kin) but, most of the TDZ-induced micro shoots showed stunted growth. Multiple shoot formation was observed on medium amended with BAP or TDZ at higher concentrations. The produced micro shoots were rooted on half strength MS medium amended with auxins and rooted plantlets acclimatized with 87% survival of the regenerates. CONCLUSIONS: The developed regeneration system can be exploited for genetic transformation studies, particularly when aimed at producing its high yielding cell lines for the anti-diabetic phytochemicals. It also offers opportunities for exploring the expression of totipotency in the anti-diabetic perennial vine.

Kernel size and weight affected by three plant bioregulators applied at bloom to Non Pareil and Carmel almond cultivars

Background: The yield of almonds [Prunus dulcis (Mill.) D.A. Webb] could be low due to climatic problems and any factor improving kernel size and weight, such as the use of plant bioregulators (PBRs), should be beneficial. Results: Three plant bioregulators: 24-epibrassinolide (BL), gibberellic acid (GA3) and kinetin (KN) were applied at three spray concentrations to Non Pareil and Carmel cultivars, at two phenological stages during bloom, in the 2014 and 2015 seasons. The results showed significant differences (P b 0.0001). For total dry weight of Non Pareil, the best treatment was BL (30 mg·L-1), with an average of 1.45 g, while the control was 1.30 g, at pink button during 2015. For Carmel, the best dry weight was 1.23 g, achieved with BL (30 mg·L-1) at fallen petals in both seasons. The average dry weight of the controls varied between 1.13 and 1.18 g. The greatest almond lengths and widths in Non Pareil were 24.98 mm and 15.05 mm, achieved with BL (30 mg·L-1) and KN (50 µL·L-1) treatments, respectively, applied at pink button in 2015. In Carmel, the greatest length and width were 24.38 and 13.44 mm, obtained with BL (30 mg·L-1) applied at the stages of pink button and fallen petals, respectively, in 2015. The control reached lengths between 22.33 and 23.38 mm, and widths between 11.99 and 12.93 mm. Conclusions: The use of the bioregulators showed significant favorable effects on dry weight, length and width of kernels at harvest, in both cultivars.

Mannheimia haemolytica growth and leukotoxin production for vaccine manufacturing: a bioprocess review

Mannheimia haemolytica leukotoxin (LKT) is a known cause of bovine respiratory disease (BRD) which results in severe economic losses in the cattle industry (up to USD 1 billion per year in the USA). Vaccines based on LKT offer the most promising measure to contain BRD outbreaks and are already commercially available. However, insufficient LKT yields, predominantly reflecting a lack of knowledge about the LKT expression process, remain a significant engineering problem and further bioprocess optimization is required to increase process efficiency. Most previous investigations have focused on LKT activity and cell growth, but neither of these parameters defines reliable criteria for the improvement of LKT yields. In this article, we review the most important process conditions and operational parameters (temperature, pH, substrate concentration, dissolved oxygen level, medium composition and the presence of metabolites) from a bioprocess engineering perspective, in order to maximize LKT yields.

Kinetin Improves Barrier Function of the Skin by Modulating Keratinocyte Differentiation Markers

BACKGROUND: Kinetin is a plant hormone that regulates growth and differentiation. Keratinocytes, the basic building blocks of the epidermis, function in maintaining the skin barrier. OBJECTIVE: We examined whether kinetin induces skin barrier functions in vitro and in vivo. METHODS: To evaluate the efficacy of kinetin at the cellular level, expression of keratinocyte differentiation markers was assessed. Moreover, we examined the clinical efficacy of kinetin by evaluating skin moisture, transepidermal water loss (TEWL), and skin surface roughness in patients who used kinetin-containing cream. We performed quantitative real-time polymerase chain reaction to measure the expression of keratinocyte differentiation markers in HaCaT cells following treatment. A clinical trial was performed to assess skin moisture, TEWL, and evenness of skin texture in subjects who used kinetin-containing cream for 4 weeks. RESULTS: Kinetin increased involucrin, and keratin 1 mRNA in HaCaT cells. Moreover, use of a kinetin-containing cream improved skin moisture and TEWL while decreasing roughness of skin texture. CONCLUSION: Kinetin induced the expression of keratinocyte differentiation markers, suggesting that it may affect differentiation to improve skin moisture content, TEWL, and other signs of skin aging. Therefore, kinetin is a potential new component for use in cosmetics as an anti-aging agent that improves the barrier function of skin.

Kinetin inhibits proliferation of hepatic stellate cells by interrupting cell cycle and induces apoptosis by down-regulating ratio of Bcl-2/Bax / 华中科技大学学报（医学）（英德文版）

Liver fibrosis is an important health problem that can further progress into cirrhosis or liver cancer, and result in significant morbidity and mortality. Inhibiting proliferation and inducing apoptosis of hepatic stellate cells (HSCs) may be the key point to reverse liver fibrosis. At present, anti-fibrosis drugs are rare. Kinetin is a type of plant-derived cytokinin which has been reported to control differentiation and induce apoptosis of human cells. In this study, the HSCs were incubated with different concentrations of kinetin. The proliferation of rat HSCs was measured by MTT assay, cell cycle and apoptosis were analyzed by flow cytometry, and the apoptosis was examined by TUNEL method. The expression of Bcl-2 and Bax proteins was detected by immunocytochemistry staining. It was found that kinetin could markedly inhibit proliferation of HSCs. In a concentration range of 2 to 8 μg/mL, the inhibitory effects of kinetin on proliferation of HSCs were increased with the increased concentration and the extension of time (P < 0.01). Flow cytometry indicated that kinetin could inhibit the DNA synthesis from G0/G1 to S phase in a dose-dependent manner (P < 0.01). The apoptosis rates of the HSCs treated with 8, 4 and 2 μg/mL kinetin (25.62% ± 2.21%, 15.31% ± 1.9% and 6.18% ± 1.23%, respectively) were increased significantly compared with the control group (3.81% ± 0.93%) (P < 0.01). All the DNA frequency histogram in kinetin-treated groups showed obvious hypodiploid peak (sub-G1 peak), and with the increase of kinetin concentrations, the apoptosis rate of HSCs also showed a trend of increase. It was also found that kinetin could down-regulate the expression of Bcl-2, and up-regulate the expression of Bax, leading to the decreased ratio of Bcl-2/Bax significantly. The kinetin-induced apoptosis of HSCs was positively correlated with the expression of Bax, and negatively with the expression of Bcl-2. It was concluded that kinetin can inhibit activation and proliferation of HSCs by interrupting the cell cycle at G1/S restriction point and inducing apoptosis of HSCs via reducing the ratio of Bcl-2/Bax.

Effects of 6-benzylaminopurine and α-naphthaleneacetic acid on growth and isoflavone contents of Pueraria phaseoloides hairy roots / 生物工程学报

In order to study the effect of phytohormone on growth and isoflavones contents of Pueraria phaseoloides hairy roots, we cultured the hairy roots with different concentrations of 6-benzylaminopurine (6-BA) alone or in combination with α-naphthaleneacetic acid (NAA). Then we determined the effects of 6-BA alone or in combination with NAA on the growth and the contents of isoflavones compounds and levels of antioxidase activities of hairy roots by spectrophotometry. The results show that 6-BA inhibited the growth, and decreased biomass and total isoflavones compounds of P. phaseoloides hairy roots. Furthermore, the inhibition was increased with the concentrations of 6-BA. Compared with the controls, different concentrations of 6-BA in combination with NAA 2.0 mg/L could inhibit the growth of hairy roots and decrease the content of total isoflavone compounds, and also significantly enhanced the contents of soluble protein and levels of peroxidase (POD) activities, but decreased the activities of superoxide dismutase (SOD). DNA ladders detected by agarose gel electrophoresis can be observed after hairy roots of P. phaseoloides were cultured with 6-BA alone for 30 days, but can appear on the 20th day after culture with 6-BA in combination with NAA 2.0 mg/L. This result indicates that 6-BA or 6-BA in combination with NAA can both stimulate appearance of programmed cell death (PCD), and NAA may play a synergistic role on PCD.

Kinetin inhibits apoptosis of aging spleen cells induced by D-galactose in rats

Kinetin (Kn) is a cytokinin growth factor that exerts several anti-aging and antioxidant effects on cells and organs. To investigate the mechanism underlying apoptotic events in aging cells induced by D-galactose (D-gal), we examined the effect of Kn delivered via nuchal subcutaneous injection on D-gal-induced aging and apoptosis in rats. Our results showed that interleukin (IL)-2 levels and mitochondrial membrane potential (DeltaPsim) were decreased by Kn in aging rats while IL-6 production and apoptosis increased. In addition, the expression of anti-apoptotic Bcl-2 was low while that of Bax was high in the aging group. After treated with Kn, compared with aging group, there showed obvious difference in Kn group with elevated IL-2, proliferation index, Bcl-2, DeltaPsim and decreased IL-6 and Bax in splenic lymphocyte. Based on these results, we concluded that Kn can effectively protect the rat spleen from aging, apoptosis, and atrophy.

Effect of kinetin on immunity and splenic lymphocyte proliferation in vitro in D-galactose-induced aging rats / 生理学报

The purpose of this paper is to study the effect of kinetin (Kn) on immunity and splenic lymphocyte proliferation in vitro of aging rats induced by D-galactose (D-gal). Fifty SD rats were randomly divided into five groups: control group, aging model group, Kn low dose group, Kn middle dose group and Kn high dose group. The aging model group was proposed by napes subcutaneous injection of D-gal (125 mg/kg) for 45 d, and anti-aging groups were intragastrically administered with 5, 10, 20 mg/kg of Kn respectively from day 11. IgG, IgA, IgM contents of serum, the apoptosis percentage, stimulation index (SI) and proliferation index (PI) of splenic lymphocyte in vitro were evaluated. The results showed that the apoptosis percentage of splenic lymphocyte in aging model rats was higher, the serum IgG, IgA and IgM contents, SI and PI were lower than control group. Kn significantly decreased the apoptosis percentage of splenic lymphocyte, while increased the serum IgG, IgA and IgM contents, SI and PI in aging model group. These results suggest that Kn could inhibit the apoptosis, while promote the proliferation of splenic lymphocyte, and then effectively enhance the immune power of the aging rats and slow down the aging process.

A novel combination of plant growth regulators for in vitro regeneration of complete plantlets of guar [Cyamopsis tetragonoloba (L.) Taub.].

A novel combination of plant growth regulators comprising indole-3-butyric acid (IBA), 6-benzylaminopurine (BA) and gibberellic acid (GA3) in Murashige and Skoog basal medium has been formulated for in vitro induction of both shoot and root in one culture using cotyledonary node explants of guar, (Cyamopsis tetragonoloba). Highest percentages of shoot (92%) and root (80%) induction were obtained in the medium containing (mg/L) 2 IBA, 3 BA and 1 GA3. Shoot regeneration from the cotyledonary node explants was observed after 10-15 days. Regeneration of roots from these shoots occurred after 20 to 25 days. The regenerated plantlets showed successful acclimatization on transfer to soil. This protocol is expected to be helpful in carrying out various in vitro manipulations in this economically and industrially important legume.

Somatic embryo-like structures of strawberry regenerated in vitro on media supplemented with 2,4-D and BAP.

Somatic embryo-like structures (SELS) were produced in vitro from leaf disk and petiole explants of two cultivars of strawberry (Fragaria × ananassa Duch) on Murashige and Skoog medium with different concentrations and combinations of 2,4‑dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP) and sucrose to check the embryonic nature of these structures histologically. A large number of SELS could be regenerated in both cultivars on media with 2 - 4 mg L-1 2,4-D in combination with 0.5 - 1 mg L-1 BAP and 50 g L-1 sucrose. Histological examination of SELS revealed the absence of a root pole. Therefore these structures cannot be strictly classified as somatic embryos. The SELS formed under the tested culture conditions represent malformed shoot-like and leaf-like structures. The importance of these results for the propagation of strawberries via somatic embryogenesis is discussed.

Biochemical markers assisted screening of Fusarium wilt resistant Musa paradisiaca (L.) cv. Puttabale micropropagated clones.

An efficient protocol was standardized for screening of panama wilt resistant Musa paradisiaca cv. Puttabale clones, an endemic cultivar of Karnataka, India. The synergistic effect of 6-benzyleaminopurine (2 to 6 mg/L) and thidiazuron (0.1 to 0.5 mg/L) on MS medium provoked multiple shoot induction from the excised meristem. An average of 30.10 ± 5.95 shoots was produced per propagule at 4 mg/L 6-benzyleaminopurine and 0.3 mg/L thidiazuron concentrations. Elongation of shoots observed on 5 mg/L BAP augmented medium with a mean length of 8.38 ± 0.30 shoots per propagule. For screening of disease resistant clones, multiple shoot buds were mutated with 0.4% ethyl-methane-sulfonate and cultured on MS medium supplemented with Fusarium oxysporum f. sp. cubense (FOC) culture filtrate (5–15%). Two month old co-cultivated secondary hardened plants were used for screening of disease resistance against FOC by the determination of biochemical markers such as total phenol, phenylalanine ammonia lyase, oxidative enzymes like peroxidase, polyphenol oxidase, catalase and PR-proteins like chitinase, β-1-3 glucanase activities. The mutated clones of M. paradisiaca cv. Puttabale cultured on FOC culture filtrate showed significant increase in the levels of biochemical markers as an indicative of acquiring disease resistant characteristics to FOC wilt.

In vitro seed germination of economically important edible bamboo Dendrocalamus membranaceus Munro.

An in vitro propagation protocol using mature seeds of D. membranaceus was successfully established. Scarcity of seeds in bamboos because of their long flowering periods and irregular seed set resulting in low viability and germination potential, motivated us to undertake the present study. The effects of sterilants, light conditions, exogenous application of plant growth regulators and temperature in overcoming germination barriers in ageing seeds of bamboo were studied. It was found that HgCl2 (0.1%) along with bleach (15%) was more effective in raising aseptic cultures. Dark conditions, high temperatures around 30 °C and soaking of seeds in GA3 solution (50 ppm) overnight stimulated high percent of seed germination with corresponding increase in shoot length (2.7±0.7 mm) and number of sprouts (2.1±0.7) per explants during culture initiation. 6-benzylaminopurine acted synergistically with kinetin to give optimum germination rate of 70±13.9% as compared to 63.13% when used individually. For prolonged maintenance of cultures, 2% sucrose was found to be suitable for promoting photomixotrophic micropropagation. Following this procedure, about 65% survival of plantlets could be achieved during hardening. Biochemically seeds consume starchy endosperm for emergence of radicle which is taken as a sign of germination as also evident from the present study. Loss of viability and vigour after a year was confirmed by Tetrazolium chloride test. Micropropagation protocol developed here will ensure regeneration of large number of plants in a relatively short time. Conclusively, in vitro propagation protocol developed in D. membranaceus using mature seeds as an explants is reported for the first time.

Effect of kinetin on ovary and uterus in D-galactose-induced female mouse model of aging / 生理学报

The present study was to investigate the effect of kinetin on ovary and uterus of D-galactose-induced female mouse model of aging. Aging female mice model caused by D-galactose were used as model group, the aging model mice intragastrically administered with kinetin solution (daily 25 mg/kg or 50 mg/kg) were used as kinetin groups, and the mice with solvent as normal group (n = 20). To detect the effects of kinetin, estrous cycle, estradiol content, ovarian and uterine wet weight and organ index, SOD and GSH-Px activities, MDA and total protein contents, as well as the reserve function of ovaries were examined. The results showed that, kinetin-induced changes in two kinetin groups were observed, compared with the model group: (1) the estrous cycle was shortened; (2) serum estradiol content was significantly increased; (3) the wet weights of the ovary and uterus were increased significantly; (4) SOD and GSH-Px activities of ovary and uterus were significantly higher; (5) the MDA contents of the ovary and uterus were reduced significantly; (6) total protein contents of the ovary and uterus were increased significantly; (7) the numbers of mature oocytes in fallopian tubes were increased significantly. The results show that kinetin can protect ovary and uterus against oxidative damage, prevent low estrogen secretion caused by ovarian oxidative damage, shorten the estrous cycle in mice, and eventually maintain ovarian and uterine vitalities.

Effect on different concentrations of exogenous hormones on baicalin in Scutellaria baicalensis callus / 中国中药杂志

<p><b>OBJECTIVE</b>To determine the content of baicalin in Scutellaria baicalensis callus induced by different doncentrations of exogenous hormones.</p><p><b>METHOD</b>HPLC system was adopted to determine baicalin in S. baicalensis callus. Chromatographic conditions: ODS column was adopted, with methanol-water-phosphate (47: 53: 0.2) as the mobile phase. The flow velocity was 1 mL x min(-1), the detective wavelength was 280 nm, and the temperature of column was room temperature.</p><p><b>RESULT</b>S. baicalensis callus induced by 6-BA 1.0 mg x L(-1) + NAA 0.5 mg x L(-1) showed the highest baicalin content, up to 49.78 mg x g(-1).</p><p><b>CONCLUSION</b>The experiment is such a simple, rapid and stable method for determining the baicalin content that it can be used for determining the baicalin content in S. baicalensis callus.</p>

Study on optimization of induction system of test-tube tuberous roots from leaves of Rehmannia glutinosa / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effect of sucrose and plant growth substances of different concentrations on the induction of test-tube tuberous roots of Rehmannia glutinosa, in order to establish an efficient system for the induction of test-tube tuberous roots from leaves of R. glutinosa.</p><p><b>METHOD</b>Leaves from test-tube seedlings of 85-5 R. glutinosa were used as explants. After rooting induction, they were transferred to medium with orthogonal design for inducing test-tube tuberous roots of R. glutinosa.</p><p><b>RESULT AND CONCLUSION</b>NAA played a significant role in induction of test-tube tuberous roots of R. glutinosa, followed by sucrose and 6-BA. With leaves from test-tube seedlings as the explants, the optimal medium for inducing test-tube tuberous roots of R. glutinosa was MS + BA 3.0 mg x L(-1) + NAA 0.1 mg x L(-1) + sucrose 7%. The study provides an efficient induction system for studies on artificial seeds and secondary metabolism with test-tube tuberous roots of R. glutinosa.</p>

Cytokinin preconditioning enhances multiple shoot regeneration in Pongamia pinnata (L) Pierre - a potential, non-edible tree seed oil source for biodiesel

An efficient, highly reproducible protocol for multiple shoot induction and plant regeneration of Pongamia pinnata has been successfully developed using cotyledonary node explants. This study also demonstrates that preconditioning of explant stimulates production of multiple shoots from cotyledonary nodes of P. pinnata. The highest direct shoot regeneration (90 percent) with an average of 18.4 +/- 3.1 shoots/explant were obtained when cotyledonary node explants were excised from seedlings germinated on Murashige and Skoog (MS) media supplemented with benzyladenine (BA) 1 mg l-1, and subsequently cultured on MS media with 1 mgl-1 thidiazuron (TDZ). Scanning electron microscope observations of cotyledonary node (CN) explants excised from pre-conditioned and normal seedlings, revealed larger buds with rapid development in BA-preconditioned CN explants. The addition of adenine sulphate significantly increased the average number of shoots per explant. The highest direct shoot regeneration (93 percent) with an average of 32.2 +/- 0.93 shoots/explant was obtained from BA-preconditioned CN when cultured on MS media supplemented with 1 mg l-1 TDZ and 200 mg l-1 adenine sulphate (ADS). Repeated shoot proliferation was observed from BA preconditioned CN explants up to 3 cycles with an average of 15 shoots/explant/cycle when cultured on MS media supplemented with 1 mg l-1 TDZ and 150 mg l-1 L-glutamine, thus producing 45 shoots/CN explant. Shoots were elongated on hormone free MS media and rooted on 1/2 MS media supplemented with 1 mg l-1 of IBA. Rooted shoots were successfully acclimatized and established in soil with 80 percent success. The highly regenerative system developed in this investigation for this important tree could be a useful tool for genetic transformation.

Characteristics of fructification and seed ripening of Panax stipuleanatus / 中国中药杂志

Characteristics of fructification and seed ripening of Panax stipuleanatus were studied in this paper with a view to better understand the species' biological characteristics and promote cultivation. Dynamic of fructification and types of fruits were observed in a period of 80 days. The seeds' biological characteristics were evaluated by observing embryo's vitality and changes in form in a period of 225 d. The findings and conclusions were as follows: A plant produces an average of (38.7 +/- 6.5) seeds; Seeds become fully mature 80 days after setting fruit, and fruits grow more rapidly in 0-40 days with an increase of 1 500.83% in fresh weight. Three types of fruits were found, that is mono-seed type, bi-seeds type and triple-seeds type, and the proportion is 9.53%, 58.66%, 1.81%, respectively. The seeds are (5.16-6. 52) mm in length and (3.12-4.95) mm in width. The weight of 1000 seeds is (0.648 +/- 0.014) g with a moisture content of (55.23 +/- 0.49)%. The after-ripening of embryo in Panax stipuleanatus is morphological form, embryos develop 75 days after the seeds' detaching from mother plant and become mature in 165-180 days with the ending of the process of after-ripening. The vitality of embryo reaches 70% , and the length of embryo is (3.217 +/- 0.406) mm and the width (0.872 +/- 0.165) mm. The seeds will germinate in 195 d.

Application of SPSS orthogonal design in tissue culture of Anoectochilus roxburghii / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effect of the different constitutions of plant hormone on the development of Anoectochilus roxburghii.</p><p><b>METHOD</b>A. roxburghii were harvested after having been cultured for 60 days. An orthogonal design was used to study the effect of NAA and 6-BA on the leaf number, eustipe number, lateral branch number of the stem tip and stem section, and the height of the stem tips. All of the data were processed by SPSS.</p><p><b>RESULT AND CONCLUSION</b>It is reported for the first time that NAA could make different development of A. roxburghii at low concentration ( < 1 mg L(-1)) and high concentration ( > 1 mg L(-1)). The optimum constitution of MS medium was NAA 0.5 mg L(-1) + 6-BA 1 mg L(-1) for the growth of the stem tip of A. roxburghii, and NAA 1 mg L(-1) + 6-BA 2 mg L(-1) for the differentiation of bud and the formation of lateral branch of the stem section. The different concentrations of NAA and 6-BA had different effects on the growth and differentiation of the stem tip and the stem section of A. roxburghii.</p>

Effects of seed priming on drought tolerence in Prunella vulgaris / 中国中药杂志

<p><b>OBJECTIVE</b>To explore an effective way to increase drought tolerance of Prunella vulgaris seed.</p><p><b>METHOD</b>The treatment of drought stress to P. vulgaris seeds was made by the different concentrations of PEG solutions. Primed seeds germinated under 25% PEG.</p><p><b>RESULT</b>As concentrations of PEG increasing, seed germination percentage, germination index and vitality index reduced. Primed with 20%-25% PEG, 300-500 mg x L(-1) GA3 and 1.6%-2.0% KNO3-KH2PO4 could enhance three population seeds germination index and vitality index under drought stress. Treated with NaCl, seeds germination percentage and germination index of two population increased, which came from Nanjing Zijinshan and Anhui Jinzhai, respectively, while those of seeds from Gansu Chengxian reduced.</p><p><b>CONCLUSION</b>Treated with PEG, GA3, KNO3-KH2 PO4 under proper concentration, seed vigor, seed resistance under drought stress would increase.</p>

Primary study on shapes of fruits and germination characters of seeds of Radix et Rhizoma Rhei / 中国中药杂志

<p><b>OBJECTIVE</b>To explore the difference of the shapes of fruits and germination characters of seeds of Rheum palmatum, R. tanguticum and R. officinale.</p><p><b>METHOD</b>The seeds of three Rheum species including wild and cultivation one were collected from different regions. Character of the fruits appearance were observed. The purification, weights per thousand seeds, content of moisture, seed vigor and different germination rates of Radix et Rhizoma Rhei were measured. The germination rates of the seeds of R. palmatum were determined under different temperature and hormone treatment .</p><p><b>RESULT</b>It was markedly variant in shapes of the fruits, rates of germination and all quality characters of the three category of Radix et Rhizoma Rhei. As reported, the size of the fruit and seed and weights per thousand seeds of R. officinale was the biggest. The seed vigor and germination rate of R. palmatum caltivated in Ming county of Gangsu were 95.7% and 94% respectively. The rate of seed vigor was closely correlated with the rate of germination for other species. Results indicated that temperature had some effects on the germination, and there were obvious difference in the active effect of gibberellin, kinetin and 6-benzyl aminopurine on the germination of the seed. Our experimental results showed that the kinetin concentration of 50 x 10(-6) g x L(-1) had the most active effect, and its rates of germination increase 18 percent than the control one.</p><p><b>CONCLUSION</b>Significant differences exist in the shapes of fruits, rates of germination of the seeds of Rheum, which are affected by the factors of temperatures and hormones. The result of this study provides scientific evidences for identify, growth and cultivation of Rheum.</p>