The research progresses and future prospects of Tetrastigma hemsleyanum Diels et Gilg: A valuable Chinese herbal medicine.

ETHNOPHARMACOLOGICAL RELEVANCE: Tetrastigma hemsleyanum Diels et Gilg, known as Sanyeqing in China, was an extensively used folk Chinese herbal medicine. This plant had been validated to be highly effective for treating high fever, pneumonia, hepatitis, gastritis, cervicitis, lymphatic tuberculosis, septicemia, and viral meningitis. AIM OF THE REVIEW: As a review in T. hemsleyanum, this article aims to provide a critical and comprehensive evaluation for future research as well as the development of new drugs. The possible uses and future research directions of this plant were also discussed. MATERIALS AND METHODS: A literature search was conducted on different scientific search engines, including Google Scholar, Science Direct, PubMed, Web of Science, and CNKI. Additional information was obtained from classic books about Chinese herbal medicine and scientific databases. RESULTS: T. hemsleyanum was a perennial herb climbing vine, which was mainly based on field cultivation. About 150 chemical compounds have been isolated from T. hemsleyanum, including flavonoids, phenolic acids, polysaccharides, triterpenoids, steroids, and organic acids. Studies on the physiological aspects of T. hemsleyanum have been focused on the effects of light and fertilizer on their growth, and few other studies have been conducted. The plant had widespread pharmacological effects on the immune system, as well as anti-tumor, anti-inflammatory, analgesic, and antipyretic. CONCLUSIONS: T. hemsleyanum was a valuable traditional Chinese medical herb with pharmacological activities that mainly affected the immune system. This review summarized its botanical description, cultivation techniques, physiology, ethnopharmacology, chemical components, and pharmacological functions. This information suggested that we should focus on the development of new drugs related to T. hemsleyanum. Meanwhile, it was important to emphasize the traditional use of T. hemsleyanum, avoiding over-harvesting that exerted a great impact on resource scarcity. And developing its new clinical usage and comprehensive utilize would augment the therapeutic potentials of T. hemsleyanum.

Vines avoid coiling around neighbouring plants infested by polyphagous mites.

Vines that coil around plants heavily infested with ambulate polyphagous mites can be heavily damaged by the mites. To explore whether vines avoid mite-infested plants, we observed the coiling responses of morning glory (Ipomoea nil var. Heavenly Blue) vines and bush killer (Cayratia japonica (Thunb) Gagnep) tendrils around nearby kidney bean (Phaseolus vulgaris L.) plants that were either uninfested or heavily infested with the two-spotted spider mite (Tetranychus urticae Koch). The proportions of I. nil vines that coiled around spider mite-infested and uninfested bean plants did not differ significantly; however, no C. japonica tendril coiled around spider mite-infested plants. The proportion of such tendrils was thus significantly lower than that around uninfested plants. The ability of C. japonica tendrils to avoid spider mite-infested plants would prevent serious "contact infections" by mites. We further found that tendril avoidance seemed to be attributable to the mite webs that covered infested plants; neither spider mite-induced bean volatiles nor spider mite intrusion onto tendrils seemed to explain the avoidance.

Left-right leaf asymmetry in decussate and distichous phyllotactic systems.

Leaves in plants with spiral phyllotaxy exhibit directional asymmetries, such that all the leaves originating from a meristem of a particular chirality are similarly asymmetric relative to each other. Models of auxin flux capable of recapitulating spiral phyllotaxis predict handed auxin asymmetries in initiating leaf primordia with empirically verifiable effects on superficially bilaterally symmetric leaves. Here, we extend a similar analysis of leaf asymmetry to decussate and distichous phyllotaxy. We found that our simulation models of these two patterns predicted mirrored asymmetries in auxin distribution in leaf primordia pairs. To empirically verify the morphological consequences of asymmetric auxin distribution, we analysed the morphology of a tomato sister-of-pin-formed1a (sopin1a) mutant, entire-2, in which spiral phyllotaxy consistently transitions to a decussate state. Shifts in the displacement of leaflets on the left and right sides of entire-2 leaf pairs mirror each other, corroborating predicted model results. We then analyse the shape of more than 800 common ivy (Hedera helix) and more than 3000 grapevine (Vitis and Ampelopsis spp.) leaf pairs and find statistical enrichment of predicted mirrored asymmetries. Our results demonstrate that left-right auxin asymmetries in models of decussate and distichous phyllotaxy successfully predict mirrored asymmetric leaf morphologies in superficially symmetric leaves.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.

Chloroplast avoidance movement is not functional in plants grown under strong sunlight.

Chloroplast movement in nine climbing plant species was investigated. It is thought that chloroplasts generally escape from strong light to avoid photodamage but accumulate towards weak light to perform photosynthesis effectively. Unexpectedly, however, the leaves of climbing plants grown under strong sunlight showed very low or no chloroplast photorelocation responses to either weak or strong blue light when detected by red light transmittance through leaves. Direct observations of Cayratia japonica leaves, for example, revealed that the average number of chloroplasts in upper periclinal walls of palisade tissue cells was only 1.2 after weak blue-light irradiation and almost all of the chloroplasts remained at the anticlinal wall, the state of chloroplast avoidance response. The leaves grown under strong light have thin and columnar palisade tissue cells comparing with the leaves grown under low light. Depending on our analyses and our schematic model, the thinner cells in a unit leaf area have a wider total plasma membrane area, such that more chloroplasts can exist on the plasma membrane in the thinner cells than in the thicker cells in a unit leaf-area basis. The same strategy might be used in other plant leaves grown under direct sunlight.

Self-discrimination in the tendrils of the vine Cayratia japonica is mediated by physiological connection.

Although self-discrimination has been well documented, especially in animals, self-discrimination in plants has been identified in only a few cases, such as self-incompatibility in flowers and root discrimination. Here, were port a new form of self-discrimination in plants: discrimination by vine tendrils. We found that tendrils of the perennial vine Cayratia japonica were more likely to coil around neighbouring non-self plants than neighbouring self plants in both experimental and natural settings. The higher level of coiling around a physiologically severed self plant compared with that around a physiologically connected self plant suggested that self-discrimination was mediated by physiological coordination between the tendril and the touched plant as reported for self-discrimination in roots. The results highlight the importance of self-discrimination for plant competition not only underground,but also above-ground.

[Resource investigation on rare and endangered She medicine Tetrastigma hemsleyanum in Zhejiang Province].

OBJECTIVE: To investigate the resource of Tetrastigma hemsleyanum which was rare and endangered plant in She nationality in Zhejiang Province. METHODS: Using literature method, survey method, plots method and line method, the resource situation of artificial planting and wild resource in Zhejiang Province were investigated. RESULTS: It was a scarce and precious medicinal herb that wild resource was rare and endangered. There were artificial planting area about 104.55 hm2 which expected to produce 173.91 tons in Zhejiang Province. CONCLUSION: In the wild,it is relatively harsh to environmental requirements for growth. Generally speaking, it takes 3 - 5 years growth period to achieve the medicinal value. The wild resource is scarce and the market demand is increasing, which brings about artificial planting to develop rapidly.

Visualization of embolism formation in the xylem of liana stems using neutron radiography.

BACKGROUND AND AIMS: Cold neutron radiography was applied to directly observe embolism in conduits of liana stems with the aim to evaluate the suitability of this method for studying embolism formation and repair. Potential advantages of this method are a principally non-invasive imaging approach with low energy dose compared with synchrotron X-ray radiation, a good spatial and temporal resolution, and the possibility to observe the entire volume of stem portions with a length of several centimetres at one time. METHODS: Complete and cut stems of Adenia lobata, Aristolochia macrophylla and Parthenocissus tricuspidata were radiographed at the neutron imaging facility CONRAD at the Helmholtz-Zentrum Berlin für Materialien und Energie, with each measurement cycle lasting several hours. Low attenuation gas spaces were separated from the high attenuation (water-containing) plant tissue using image processing. KEY RESULTS: Severe cuts into the stem were necessary to induce embolism. The formation and temporal course of an embolism event could then be successfully observed in individual conduits. It was found that complete emptying of a vessel with a diameter of 100 µm required a time interval of 4 min. Furthermore, dehydration of the whole stem section could be monitored via decreasing attenuation of the neutrons. CONCLUSIONS: The results suggest that cold neutron radiography represents a useful tool for studying water relations in plant stems that has the potential to complement other non-invasive methods.

Requerimientos germinativos de enredaderas características del Chaco Serrano de Córdoba, Argentina / Germinating requirements of common vines from Chaco Serrano of Córdoba, Argentina

Vines are conspicuous elements of floras in different ecosystems. Patterns of distribution and ecology of this group has been studied at regional scales, mainly in tropical areas, but less is known about factors affecting their distribution at smaller scales. In this study, the germinating requirements of common vines from two plant communities (open shrubland and woodland) in xerophytic mountain forests (Chaco serrano) were studied. A total of 21 species were selected and classified as typical of woodland, shrubland, or indifferent. Experimental treatments were three temperature regimes (15-5ºC, 25-15ºC and 35-20ºC), in light (12-12h daily photoperiod) and in continuous darkness. Total germination percentage, the relative light germination (RLG) and germination rate (T50) were recorded. Among results we found that the temperature was the main factor triggering the germination process. No differences in the mean RLG and T50 between woodland and shrubland patches were found. The patterns observed in this work support the idea that, independently of patch type, germination is associated with temperature of the time of the year when most of the rainfall occurs. Germination of the studied species would be responding to macroclimate’s factors (seasonality of climate and rainfall), rather than to a microclimate. This indicates that differences in species composition between patches would not be due to the factors studied, rather than to characteristics of the later stages of the cycle life.

Las enredaderas son elementos conspicuos de la flora de diferentes ecosistemas. Numerosos estudios basados en patrones de distribución y ecología de este grupo de plantas se han realizado a escala regional, se conoce poco sobre los factores que afectan su distribución a nivel local. Se estudiaron los requerimientos germinativos de 21 enredaderas del Bosque chaqueño serrano de Córdoba, las cuales fueron clasificadas en típicas de bosques, matorrales e indiferentes. Se llevaron a cabo experimentos de germinación en tres regímenes de temperatura (15-5ºC, 25-15ºC y 35-20ºC), en luz (12-12hr luz-oscuridad) y oscuridad permanente. Se registró el porcentaje final de germinación, el índice de germinación relativa a la luz (GRL) y la velocidad de germinación (T50). La temperatura fue el principal factor regulador del proceso germinativo. El GRL y el T50 no registraron diferencias entre fisonomías. Los patrones observados apoyan la idea de que la germinación de este grupo de plantas estaría respondiendo a factores macroclimáticos (estacionalidad del clima y las precipitaciones), más que a un microclima (factores asociados a la fisonomía del sitio). La composición diferencial de enredaderas en los parches de bosques y arbustos no estaría explicada por los factores estudiados, sino por características de las etapas posteriores a la semilla.

[Germinating requirements of common vines from Chaco Serrano of Córdoba, Argentina]. / Requerimientos germinativos de enredaderas características del Chaco Serrano de Córdoba, Argentina.

Vines are conspicuous elements of floras in different ecosystems. Patterns of distribution and ecology of this group has been studied at regional scales, mainly in tropical areas, but less is known about factors affecting their distribution at smaller scales. In this study, the germinating requirements of common vines from two plant communities (open shrubland and woodland) in xerophytic mountain forests (Chaco serrano) were studied. A total of 21 species were selected and classified as typical of woodland, shrubland, or indifferent. Experimental treatments were three temperature regimes (15-5 degrees C, 25-15 degrees C and 35-20 degrees C), in light (12-12h daily photoperiod) and in continuous darkness. Total germination percentage, the relative light germination (RLG) and germination rate (T50) were recorded. Among results we found that the temperature was the main factor triggering the germination process. No differences in the mean RLG and T50 between woodland and shrubland patches were found. The patterns observed in this work support the idea that, independently of patch type, germination is associated with temperature of the time of the year when most of the rainfall occurs. Germination of the studied species would be responding to macroclimate's factors (seasonality of climate and rainfall), rather than to a microclimate. This indicates that differences in species composition between patches would not be due to the factors studied, rather than to characteristics of the later stages of the cycle life. 1523. Epub 2012 December 01.

[Callus cultivation and determination of flavonoids from Tetrastigma hemsleyanum].

OBJECTIVE: The feasibility of producting flavonoids from callus of Tetrastigma hemsleyanum was investigated through callus induction, proliferation, differentiation and determination of flavonoids. METHODS: The leaves of sterile plantlet, leaves and stems of wild plants were used as explants to induce calluses; The root tuber, the leaves and calluses were selected for the determination of flavonoids. With ethanol as the solvent, the total flavonoids were extracted by ultrasonic and determined by spectrophotometry at 500 nm after stained with NaNO2-Al(NO3) 3. RESULTS: The optimum medium where the calluses were induced was 2/3MS +2.0 mg/L 6-BA +2.0 mg/L NAA; MS +2.0 mg/L 6-BA +2.0 mg/L NAA was the optimum for callus proliferation; for callus root differentiation, the optimum medium was 1/2MS +1.0 mg/L 6-BA +1.0 mg/L NAA. The content of total flavonoids was 31.121 mg/g in root tuber, 12.830 mg/g in leaves while it was up to 18.088 mg/g in calluses. CONCLUSION: The calluses had a high level of total flavonoids, it could produce flavonoids through the calluses induced by Tetrastigma hemsleyanum in a large scale. In that case, the pressing requirement in medical market will be solved.

[Effects of nitrogen supply on Parthenocissus tricuspidata seedling morphology and nitrogen allocation].

With hydroponic culture, this paper studied the effects of different nitrogen (N) supply levels (0, 0.15, 0.3, 0.45, 0.6, 0.75 g N x L(-1)) on the seedling morphology and N allocation of Parthenocissus tricuspidata. The results showed that lower N supply retarded the development of P. tricuspidata seedling's branch; while higher N supply had significant effects in promoting the seedling's early branching and lowering the branching position on the main stem. Supplying higher amount of N increased the plant biomass and the N concentration in root, leaf and stem significantly. Compared with stem and root, leaf had the highest biomass, accounting for 50% of the total biomass, and the highest N accumulation, accounting for 60%-70% of the total accumulated N.