Plant growth promoting Pseudomonas aeruginosa from Valeriana wallichii displays antagonistic potential against three phytopathogenic fungi.

The soil nature and characterstics are directly related to the micro-organisms present, bio-mineralization process, plant type and thus having harmonius and interdependent relationships. Soil bacteria having antagonistic activity against phytopathogens, play an important role in root growth, overall plant growth and also their composition depends upon the plant species. Population explosion across globe has resulted in indiscriminate use of chemical fertilizers, fungicides and pesticides, thus posing serious risk to plant productivity and soil flora. Plant growth promoting rhizobacteria (PGPRs) are considered safer than chemical fertilizers as they are eco-friendly and sustain longer after colonization in rhizospheric soil. PGPRs are preferred as a green choice and acts as a superior biocontrol agents against phytopathogens. In the present study, a potential rhizobacteria, Pseudomonas aeruginosa (isolate-2) was isolated from the rhizosphere of a medicinal plant, Valeriana wallichi. The bacterial isolate exhibited qualitative tests for plant growth promoting determinatives. It was also subjected to in-vitro biocontrol activity against potential phytopathogens viz. Alternaria alternata, Aspergillus flavus and F. oxysporum. The antagonistic efficacy against F. oxysporum was 56.2% followed by Alternaria alternata to be 51.02%. The maximum inhibition of radial growth of F. oxysporum was 69.2%, Alternaria alternata (46.4%) and Aspergillus flavus (15%). The Pseudomonas aeruginosa exhibited plant growth promotion rhizobacterial activity which can be expoited as biofertilizers. This study deals with microbial revitalization strategy and offers promising solution as a biocontrol agent to enhance crop yield. Further, PGPRs research using the interdisciplinary approaches like biotechnology, nanotechnology etc. will unravel the molecular mechanisms which may be helpful for maximizing its potential in sustainable agriculture.

Diversity of endophytic plant-growth microorganisms from Gentianella weberbaueri and Valeriana pycnantha, highland Peruvian medicinal plants.

Microbial diversity in Peruvian mountain areas is poorly know, specially endophytic microorganisms of medicinal native plants from the Cordillera Blanca. So, nine bacterial and six fungal species were isolated from Gentianella weberbaueri and Valeriana pycnantha. According to 16S rDNA analysis, bacterial strains belong to genera Rahnella, Pseudomonas, Serratia, Rouxiella, and Bacillus; while ITS analysis showed that fungi belong to Pyrenochaeta, Scleroconidioma, Cryptococcus, and Plenodomus genera. Rahnella sp. GT24B and P. trivialis VT20B solubilized tricalcium phosphate and produced siderophores at 10 and 24 °C. Five bacteria strains produced indol-3-acetic acid (IAA) at 10 and 24 °C, where Rahnella sp. VT19B showed more production at 10 °C than 24 °C. Rahnella sp. GT24B, Serratia sp. VT28B, and Rahnella sp. GT25B inhibited Fusarium oxysporum growth up to 100, 78 and 74 %, respectively. R. inusitata VT25B and B. licheniformis GT10B showed high cellulolytic and proteolytic activities. On the other hand, only a few fungi moderately inhibited growth of F. oxysporum, and produced siderophores and cellulases. Most of bacteria inoculated on Medicago sativa "alfalfa" and Triticum aestivum "wheat" seeds got better root development, especially Rahnella sp. GT24B, Rouxiella sp.VT24B, Serratia sp. VT28B, and Rahnella sp. VT34B. Finally, this study is the first report of endophytic microorganisms associated to wild medicinal high-mountain Peruvian plants and it show a valuable microbial diversity and its possible role in promoting growth of crops and wild medicinal plants.

Biología de Valeriana pilosa R. &. P. (Valerianaceae): una especie en peligro de extinción de las altas montañas de Perú / Valeriana pilosa R. &. P. (Valerianaceae) biology: an endangered species in the high mountains of Peru

El estudio se realizó en un área de vegetación natural en Campo Alegre (3708 msnm), centro poblado de Huanico, distrito de Namora, Cajamarca (Perú), donde Valeriana pilosa R. & P. crece espontáneamente. Se describió la planta, la semilla, la regeneración natural, la fenología de las poblaciones, el área foliar y la asignación de la materia seca a los órganos de las matas adultas. Se realizaron pruebas de germinación y se evaluó el crecimiento de las plántulas. La planta vive en el pajonal, asociada, principalmente, a especies de Calamagrostis y Stipa. Se regenera mediante semilla, bajo la protección de las plantas acompañantes. La fenología de las poblaciones estuvo relacionada con la temperatura y la precipitación pluvial. El área foliar por mata fue de 925 cm2 y el índice de cosecha promedio de 35.8 por ciento. Mil semillas pesaron 0.2 g y tuvieron 43 por ciento de germinación. Las plántulas crecieron 5.6 mm mes-1.

The study was conducted in an area of natural vegetation in Campo Alegre (3708 m), Huanico, Namora district, Cajamarca (Perú), where Valeriana pilosa R. & P. (“valeriana”) grows spontaneously. Plant, seed, natural regeneration, phenology of populations, leaf area and dry matter allocation of the organs of adult bush were described. Germination tests were performed and the growth of seedlings was evaluated. The plant lives in the scrubland, mainly associated with species of Calamagrostis and Stipa. It is regenerated by seed, under the protection of companion plants. The phenology of populations was related to temperature and rainfall. The leaf area per plant was 925 cm2 and the average harvest index of 35.8 percent. Thousand seeds weighed 0.2 g and had 43 percent germination. Seedlings were grown 5.6 mm month-1.

Impact of Altitudes and Habitats on Valerenic Acid, Total Phenolics, Flavonoids, Tannins, and Antioxidant Activity of Valeriana jatamansi.

The changes in total phenolics, flavonoids, tannins, valerenic acid, and antioxidant activity were assessed in 25 populations of Valeriana jatamansi sampled from 1200 to 2775 m asl and four habitat types of Uttarakhand, West Himalaya. Significant (p < 0.05) variations in total phenolics, flavonoids, valerenic acid, and antioxidant activity in aerial and root portions and across the populations were observed. Antioxidant activity measured by three in vitro antioxidant assays, i.e., 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic) (ABTS) radical scavenging, 2,2'-diphenyl-1-picryylhydrazyl (DPPH) free radical scavenging, and ferric-reducing antioxidant power (FRAP) assays, showed significant (p < 0.05) differences across the populations. However, no clear pattern was found in phytochemicals across the altitudinal range. Among habitat types, (pine, oak, mixed forest, and grassy land), variation in phytochemical content and antioxidant activity were observed. Equal class ranking, neighbor-joining cluster analysis, and principal component analysis (PCA) identified Talwari, Jaberkhet, Manjkhali, and Khirshu populations as promising sources with higher phytochemicals and antioxidant activity. The results recommended that the identified populations with higher value of phytochemicals and antioxidants can be utilized for mass multiplication and breeding program to meet the domestic as well as commercial demand.

In vitro propagation of the Garden Heliotrope, Valeriana officinalis L.: influence of pre-chilling and light on seed germination.

Valeriana officinalis is an important medicinal herb commonly found in Kashmir valley. This study forms an important preliminary step for in-vitro micro propagation of V. officinalis from breaking the seed dormancy, inducing rapid seed germination and its subsequent micro propagation. We investigated the influence of pretreatment of V. officinalis seeds with reduced temperature and light on seed germination and in-vitro propagation. Culture of explants from cultivated seeds have demonstrated its potential for in vitro propagation and plantlet regeneration. Individual as well as combinations of treatments such as temperature and light availability influenced the germination of seeds variedly. Unchilled seeds of V. officinalis were given dip in GA3 (200 ppm) for 24, 48 and 120 h. Seeds treated with GA3 for 24 h and kept in darkness showed the best results, i.e. 48%. Seeds pretreated with GA3 for 120 h and incubated in dark showed 40% germination. Pre-chilling up to 72 h and kept in light showed maximum germination of 60% followed by 40% kept in darkness. Pre-chilling for 48 h resulted in 40 and 25% seed germination in light and darkness, respectively. GA3 pre-treatment for 72 h and 24 h pre chilling were most effective in inducing seed germination. Maximum shoot response was obtained on MS enriched with BAP (1 mg/L) + IAA (0.1 mg/L) combinations using shoot tips as explants. Multiple shoot regeneration from shoot apices was recorded on BAP (1 mg/L) and BAP (1 mg/L) + IAA (0.1 mg/L).

[The research of Valeriana amurensis seed germination characteristics].

OBJECTIVE: To study the effect of different treatments on the Valeriana amurensis seed germination rate. METHODS: Used different chemical reagents and seed soakings on the routine germination test and the orthogonal test of the Valeriana amurensis seed, calculated the germination rate under different germination condition. RESULTS: Valeriana amurensis treated with different chemical reagends had different germination rate. The suitable immersion time could enhance Valeriana amurensis seed germination rate. Different treatment time, different disposal temperature, different germination temperature would have an impact on the Valeriana amurensis seed germination rate. CONCLUSION: In order to raise the Valeriana amurensis seed germination rate, use appropriate treatment on the seed before plant seeds; The seed growing must under suitable time and temperature.

Developmental and cytogenetic analyses of pollen sterility in Valeriana scandens L.

Valeriana scandens presents perfect and pistillate flowers, the latter with sterile anthers. The species is composed of two varieties with different ploidy; V. scandens var. scandens (2n = 28) and V. scandens var. candolleana (2n = 56), both of which occur in RS, Brazil. Crosses between these varieties may give rise to hybrids with pollen sterility. In this study, we analyzed the microsporogenesis and microgametogenesis of sterile and fertile anthers, and also investigate whether pollen sterility is caused by an irregular meiotic process. Developmental analysis using light microscopy and scanning electron microscopy showed that sterile anthers develop similarly to fertile anthers until the end of meiosis. After this stage, sterile tetrads do not separate as a consequence of exine fusion between adjacent microspores, which is similar to sterile pollen of Brassica ms-cdl1 mutants. In addition, vacuolated immature pollen grains degenerate after separation. The cytogenetic analysis of the microspore mother cell (MMC) showed that the diploid population of V. scandens var. scandens (2n = 28) has pollen sterility that is not caused by a cytogenetic disturbance. The MMCs analyzed from prophase I to tetrad stage showed a regular meiotic process, indicating the phenotype of V. scandens sterile pollen is a postmeiotic process formed by fusion of exine between opposite microspores.

Root colonization by symbiotic arbuscular mycorrhizal fungi increases sesquiterpenic acid concentrations in Valeriana officinalis L.

In some medicinal plants a specific plant-fungus association, known as arbuscular mycorrhizal (AM) symbiosis, increases the levels of secondary plant metabolites and/or plant growth. In this study, the effects of three different AM treatments on biomass and sesquiterpenic acid concentrations in two IN VITRO propagated genotypes of valerian ( VALERIANA OFFICINALIS L., Valerianaceae) were investigated. Valerenic, acetoxyvalerenic and hydroxyvalerenic acid levels were analyzed in the rhizome and in two root fractions. Two of the AM treatments significantly increased the levels of sesquiterpenic acids in the underground parts of valerian. These treatments, however, influenced the biomass of rhizomes and roots negatively. Therefore this observed increase was not accompanied by an increase in yield of sesquiterpenic acids per plant. Furthermore, one of the two genotypes had remarkably high hydroxyvalerenic acid contents and can be regarded as a hydroxyvalerenic acid chemotype.

[HPLC fingerprint of the antiarrhythmic fraction of Valeriana officinalis].

OBJECTIVE: To establish HPLC fingerprints of the Antiarrhythmic fraction of Valeriana officinalis. METHODS: Agilent C18 (250 mm x 4.6 mm, 5 microm) column was used and the acetonitrile-water was chosen as the mobile phase in a gradient mode. The column temperature was 380 degrees C and the detection wavelength was 218 nm. The detection time was 70 min, and the flow rate was 1.0 mL/ min. RESULTS: Fifteen characteristic peaks were indicated in HPLC fingerprints. The relative retention time and the ranges of relative areas of the common peaks were also determined. CONCLUSION: This method is simple and accurate with a good reproducibility and provides a reference standard for the quality control of Valeriana officinalis.

Control of development and valepotriate production by auxins in micropropagated Valeriana glechomifolia.

Valeriana glechomifolia is a plant species endemic to southern Brazil that accumulates valepotriates, which are terpene derivatives, in all of its organs. Valepotriates are the presumed sedative generic components of the pharmaceutically used species of Valeriana. The influence of various concentrations of the auxins indole-3-acetic acid, indole-3-butyric acid and alpha-naphthaleneacetic acid on the growth of micropropagated V. glechomifolia was investigated under conditions of transient and continuous exposure. Changes in the development of roots and shoots as well as the production of the valepotriates acevaltrate, valtrate and didrovaltrate (analyzed by high-performance liquid chromatography) were evaluated. The best performance in valepotriate production, growth and survival under ex vitro conditions following plant acclimatization was achieved in the continuous presence of 5.71 microM IAA. When cultured in medium containing IAA plants produced stable levels of valepotriates throughout the entire cultivation period.

Essential oil of Valeriana officinalis L. cultivars and their antimicrobial activity as influenced by harvesting time under commercial organic cultivation.

The essential oil content and the composition of subterranean parts of two valerian (Valeriana officinalis, L.) cultivars Select and Anthose, from certified commercial organic fields, were determined by hydrodistillation, followed by gas chromatography (GC) and GC/mass spectrometry analysis. Eight and fourteen month old cv. Select had 0.67 and 0.87% essential oil, while similar aged cv. Anthose contained 0.97 and 1.1% essential oil. Forty-three and fifty-three components from cv. Select and cv. Anthose oils were detected, respectively. The oil composition significantly varied due to the cultivar type, plant age, and/or harvesting time. The major components for cv. Select were valerenal, bornyl acetate, 15-acetoxy valeranone, valerenic acid, and camphene, while cv. Anthose had valerenal, (-)-bornyl acetate, alpha-humulene, camphene, 15-acetoxy valeranone, and valerenic acid. With further aging of the plants, the valerenal, valerenic acid, and alpha-humulene contents increased. The oil of cv. Select had a strong antimicrobial effect against Aspergillus niger, Escherichia coli, Staphylococcus aureus, and Saccharomyces cerevisiae, while cv. Anthose showed low or no activity against all test microbes, including Pseudomonas aeruginosa, suggesting that the inhibitory activity of valerian oil depends on the cultivar and its developmental stage. The oil profile of our cultivars did not match the literature proposed chemotype profiles.

Comparative study of differentiation levels and valepotriate content of in vitro cultures and regenerated and wild plants of Valeriana edulis ssp.procera.

Valepotriate content levels in samples of in vitro cultures of Valeriana edulis ssp. procera were compared with those of roots and rhizomes of wild plants in the reproductive stage. Rhizomes and roots of regenerated and wild plants showed a similar valepotriate content. The data obtained support the hypothesis that valepotriate production in V. edulis spp. procera is closely related to rhizome and root differentiation. The large-scale propagation of this endangered plant may offer an attractive alternative for its production for medicinal purposes.

Valepotriate content in different in vitro cultures of Valerianaceae and characterization of Valeriana officinalis L. callus during a growth period.

Different in vitro cultures of Valerianaceae were analysed for valepotriate content [(iso)valtrate, acevaltrate, didrovaltrate] in a study on properties of production in vitro (plant species, growth conditions, differentiation level, valepotriate content of the medium after growth). The in vitro cultures were: callus cultures of Valeriana officinalis L., Valerianella locusta L. and Centranthus ruber L.DC.; a suspension culture of Valeriana officinalis L. and a root organ culture of Centranthus ruber L.DC. All of the cultures produced valepotriates in vitro in different amounts. None of the media that had served for growth contained any valepotriates. In order to characterize the in vitro growth more precisely different parameters were analysed at different time intervals during a growth period in one of the cultures (callus culture of Valeriana officinalis L.). These different parameters were: fresh and dry weight, lipid and nitrogen content and (iso)valtrate content. This study during a growth period was performed on two media differing in plant hormone content.

[Chemical weed control in the cropping of medicinal plants. Part 1: Valerian (Valeriana officinalis L.) (author's transl)]. / Chemische Unkrautbekämpfung in Arzneipflanzenkulturen. 1. Mitteilung: Baldrian (Valeriana officinalis L.).

More than 40 herbicides have been tested in field trials with valerian over a period of several years. The following herbicidies have proved best suited: chloropham for application in autumn after planting, metobromurone for spraying in the early spring at the commencement of sprouting, nitrofen or a nitrofen-simazine compound preparation for application in May. The utilization of a sequence of herbicides led to a 90% reduction of the weed cover and a 65% reduction of the manual work needed for weed control. The yield and the essential oil and valepotriate contents of valerian were not impaired. The results from residue analyses are presented.