Wild-grown Plants Research Articles

Variación en grados de latencia en semillas entre colectas de chile piquín ( Capsicum annuum var. glabriusculum )

El chile piquín ( Capsicum annuum var. glabriusculum ) que se consume en México es, en su mayoría, recolectado de plantas silvestres. Esta actividad podría amenazar la diversidad genética de la especie. Idealmente, el chile piquín debería producirse intensivamente para proteger la población silvestre y satisfacer la demanda; sin embargo, la baja germinación de semillas de esta especie de chile ha sido tradicionalmente un problema para su establecimiento a nivel comercial. Las causas de lo anterior son desconocidas. Identificar las causas de la baja germinación y la diversidad entre colectas es, por tanto, de importancia. Se evaluaron 16 diferentes colectas de chile piquín provenientes de siete estados del país y del sur de Estados Unidos. Un estudio morfológico determinó que en las colectas evaluadas no existen diferencias ni barreras morfológicas que impidan la germinación apropiada de las semillas. Una cinética de imbibición determinó que no existen impedimentos físicos para el paso apropiado de agua al interior de las semillas; sin embargo, la germinación de las 16 colectas fue muy variable (0 a 66%), con un promedio de 15%. El pretratamiento de las semillas con la hormona AG3 (5,000 ppm), elevó la tasa promedio de germinación a 59% en 14 de las 16 colectas, mientras que los tratamientos de acondicionamiento con peróxido de hidrógeno y nitrato de potasio solamente mejoraron la germinación de semillas en dos y cuatro colectas, respectivamente. El presente trabajo corrobora que la limitante de germinación en semillas de chile piquín se debe a un fenómeno de latencia fisiológica, la cual puede romperse con aplicación exógena de AG3 a 5,000 ppm, cuyos efectos varían entre colectas.

English

Plant biotechnology enables the production of biomass under controlled conditions, providing the synthesis of raw material in a continuous and homogeneous way. The aim of the present study was to establish Hovenia dulcis callus cultures and to evaluate their antioxidant potential in comparison with wild grown and in vitro plants. The best results for compact calli were obtained with the supplementation of 1-naphthaleneacetic acid (NAA) at 2.5 mg L-1 and the use of benzylaminopurine (BAP) enhanced callus growth. The medium supplemented with 2.5 mg L-1 NAA + 0.65 mg L-1 BAP produced 115.3±28.2 mg of dry weight. The auxin NAA was responsible for the production of light-green compact callus, while picloram and 2,4-D promoted mixed (friable and compact) calli. Total polyphenols and total flavonoids were found in higher concentrations in wild grown plants, whereas the reduction capacity and DPPH radical scavenging assays recorded higher antioxidant activity in calluses extracts. The protocols established here represent a viable and effective way for producing substances with medicinal interest.   Key words: Tissue culture, total phenolics, total flavonoids, 2,2-diphenyl-1-picrylhydrazyl (DPPH), medicinal plant.

An Efficient In Vitro Propagation, Antioxidant and Antimicrobial Activities of Aphyllorchis Montana (Reichenb.f.)

An in vitro plant regeneration protocol was successfully established in Aphyllorchis Montana , a saprophytic achlorophyllous orchid by culturing immature seeds. Among the six basal media evaluated for seed germination, BM-TM medium was found to be the best followed by KC medium. After 40 days, all the media turned brown and the growths of the protocorms were arrested. Activated charcoal, 1 g/l in half strength BM-TM was found to be suitable for further development of protocorms. Half strength BM-TM medium was supplemented with different growth regulators either individually or in combinations for multiplication of shoots. Of the five cytokinins tested, TDZ at 6.8 μM was found to be most effective for multiple shoot induction yielding 17.24 ± 0.27 shoots after 10 weeks of culture. Addition of low concentration of NAA (1.3 μM) in MS medium supplemented with the cytokinin TDZ (6.8 μM) favoured shoot multiplication. A mean number of 27.56 ± 0.54 shoots with 3.92 ± 0.11 number of roots were produced per explant. The response of the seed derived protocorm to the different types of organic additives viz., peptone and yeast extract and coconut water was also evaluated. The addition of these organic additives to the medium containing TDZ enhanced the number of shoot regeneration. The plantlets were acclimatized in plastic pots containing sterilized vermiculite. The survival rate was 100 % when maintained in the culture room condition (25 ± 2 °C). Screening of the antibacterial, antioxidant activity and estimation of total phenolics and flavonoid content of methanolic extracts of micropropagated plants were also carried out and compared with that of the wild-grown plants. In all the tests, methanolic extract from wild-grown plants showed higher antioxidant, antimicrobial activity, total phenolics and flavonoid content than in vitro propagated plants.

Micropropagation, antioxidant properties and phytochemical assessment of Swertia corymbosa (Griseb.) Wight ex C. B. Clarke: a medicinal plant

Swertia corymbosa (Griseb.) Wight ex C. B. Clarke, a valuable medicinal plant, has been investigated for its regeneration potential using nodal explants. Out of a range of concentrations of cytokinins [6-benzyl adenine (BA), 6-furfurylaminopurine (Kn), 2-isopentenyl adenine (2iP), thidiazuron (TDZ), and zeatin (Z)] used as supplements with MS, BA at 4.40 μM concentration proved best for multiple shoot induction yielding 26.50 ± 0.26 shoots after 12 weeks of culture. Addition of low concentration of NAA (1.3 μM) in MS medium supplemented with the cytokinin BA (4.40 μM) favoured shoot multiplication. A mean number of 35.78 ± 0.81 shoots were produced per explant. Additive effect of BA (4.40 μM) in combination with Kn (4.64 μM) produced highest number of shoots (83.20 ± 4.29). Addition of GA3 (1.4 μM) to the above medium not only favored shoot elongation but also enhanced the number of shoots (113.98 ± 3.80). The microshoots were rooted successfully on half-strength MS medium supplemented with 9.8 μM of IBA. The plantlets were successfully transferred to hardening medium containing vermiculite with 87 % survival rate. Screening of the antibacterial, antioxidant activity and estimation of total phenolic and flavonoid content of methanolic extracts of micropropagated plants were also carried out and compared with that of the wild-grown plants. In all the tests, methanolic extract from wild-grown plants showed higher antioxidant, antimicrobial activity, total phenolic and flavonoid content than in vitro propagated plants. The content of secondary metabolites in wild-grown plants and in vitro propagated plants was determined by HPLC coupled with ESI-MS and the presence of loganic acid, swertiamarin, sweroside, gentiopicroside, isovitexin, amoroswertin, amarogentin, gentiacaulein, decussatin, and swertianin in the samples were confirmed. Gentiopicroside (40.726 mg/g) and swertianin (29.598 mg/g) were found to be the major compounds which may be responsible for the antimicrobial and antioxidant activities. The results of the present study confirmed the therapeutic potency of S. corymbosa used in the traditional medicine; in addition, the protocol for in vitro production developed in the present study could be applied for mass multiplication and for the conservation of germplasm.

Mechanisms underlying plant sexual dimorphism in multi‐trophic arthropod communities

A growing body of research documents the importance of plant genetic effects on arthropod community structure. However, the mechanisms underlying these effects are often unclear. Additionally, plant genetic effects have largely been quantified in common gardens, thus inflating the estimates of their importance by minimizing levels of natural variation. Using Valeriana edulis, a dioecious plant with genetically based sex determination, we conducted surveys and experiments on wild-grown individuals to document field patterns of arthropod association between the sexes and the mechanisms underlying these plant genetic effects. Three years of surveys revealed strong and consistent sex-biased arthropod association in wild-grown plants: female plants supported 4-fold, 1.5-fold, and 4-fold higher densities of aphids, aphid predators, and aphid-tending ants, respectively, compared to males. There was mixed evidence that the female bias for aphids was due to higher plant quality, while we found no difference between plant sexes in aphid preference or the top-down effects of predators and tending ants. Female bias for ants was due to both the greater attractiveness of female plants (direct effect mediated by floral nectar) and an independent, weaker effect of higher aphid abundance on females (density-mediated indirect effect). Conversely, the female bias for predators was driven solely by the greater attractiveness of female plants. We did not find interaction modification, i.e., ant-aphid and predator-aphid interactions were equivalent between plant sexes. Plant sex explained 0.24%, 2.28%, and 4.42% of the variance in aphids, predators, and ants, respectively, values comparable to but slightly weaker than those previously reported from common-garden studies. In contrast to the prediction of diminished plant genetic effects with increasing trophic level, we show how weak indirect effects on predators and parasitoids (via herbivores) can be complemented by strong direct effects via common plant traits (floral resources). In summary, we document direct and indirect effects of genetically based sex on a multi-trophic arthropod community that were expressed in wild-grown plants across multiple years.

Chemical composition and antifungal activity of Hypericum perforatum subsp. angustifolium roots from wild plants and plants grown under controlled conditions

The medicinal properties of the aerial parts of Hypericum perforatum subsp. angustifolium have been extensively investigated, yet little is known about the chemical composition or potential uses of the root extracts. In this study, xanthone production in wild plants and plants grown under controlled conditions was investigated. Chemical analyses carried out on wild plants revealed that xanthones were mainly accumulated in the roots. We mainly detected 1,7-dihydroxyxanthone, paxanthone, 5-O-methyl-2-deprenylrheediaxanthone B, kielcorin. The roots of wild plants showed low xanthone accumulation. In the roots of plants grown under controlled conditions, xanthone accumulation was 27 times greater than that in the roots of wild-grown plants. Kielcorin was not detected in the roots of plants grown under controlled conditions. As xanthones are known for their antifungal activity, the extracts from both samples were tested against the human fungal pathogens Candida albicans, non-albicansCandida species, Cryptococcus neoformans, and dermatophytes. The root extracts from plants grown under controlled conditions showed greater antifungal activity, probably correlated with higher xanthone accumulation.

Characterization of Schoenoplectus pungens in a Great Lakes Coastal Wetland and a Pacific Northwestern Estuary

This study seeks to identify key components of structure and growth habit of Schoenoplectus pungens (bulrush) that allow it to thrive in severe environments. Schoenoplectus pungens, an emergent herbaceous plant growing in shallow, high energy freshwater and brackish coastal wetlands, occurs throughout North America and several continents. We observe the plant in ecologically distinctive Laurentian Great Lakes and Pacific Northwestern estuaries. Plant populations were characterized in terms of above-ground and below-ground biomass, stem density, diameter, height, and flexibility. Plants grown in flooded planters for research were compared with populations in their natural environments. The modulus of elasticity was found to be similar for planter- and wild-grown plants from fresh and brackish waters. Aerenchyma tissue, important for conducting oxygen to roots, increased with flooding and possibly reduced stem flexibility. Stem diameter and height increased as water depths or flooding increased, while below-ground biomass decreased. Soils ranging from coarse gravels to clays supported S. pungens. Most regeneration occurs as sprouts from rhizomes, not seedlings. Below-ground biomass accounted for a greater proportion of total biomass than above-ground biomass in most zones. This study collected large below-ground biomass samples that allowed for more effective evaluation of root and rhizome structure than traditional small samples.

Alternaria Black Spot of Crucifers: Symptoms, Importance of Disease, and Perspectives of Resistance Breeding

Alternaria Black Spot of Crucifers: Symptoms, Importance of Disease, and Perspectives of Resistance Breeding Alternaria black spot of cruciferous vegetables, incited by different species of Alternaria, remains an increasing threat to Brassicaceae crops throughout the world, including Poland. Brassica plants are attacked by conidia of A. brassicae (Berk.) Sacc., A. brassicicola (Schw.) Wiltsh., A. raphani Groves & Skolko, and A. alternata (Fr.) Kreissler. The pathogens have a wide spectrum of hosts, such as head cabbage, Chinese cabbage, cauliflower, broccoli, and other crucifers including cultivated and wild grown plants. Alternaria pathogens usually cause damping-off of seedlings, spotting of leaves of cabbages, blackleg of heads of cabbages, and spotting of cauliflower curds and broccoli florets. In oilseed rape, A. brassicae is the dominant invasive species, while in the cruciferous vegetables, both species, A. brassicae, and A. brassicicola are encountered. Infected seeds with spores on the seed coat or mycelium under the seed coat are the main means of distribution for these pathogens. The fungus can overwinter on susceptible weeds or crop debris and on seed plants, as well as on stecklings. Methods for disease prevention and control are based on combining agricultural management practices with chemical control. Using disease-free seeds or seeds treated with fungicides can greatly reduce disease incidence. After appearance of the first symptoms of disease, stringent fungicide spray program is an effective way to reduce losses. Many authors seem to agree, that the most economically feasible method of disease control is the development of resistant Brassicaceae crops varieties, as transgenic approach proved unsuccessful. Due to our increasing understanding of pathogen-host plant interactions, identification of resistance sources, and assessment of the resistance trait inheritance mode, breeding programs of Brassica crops for Alternaria resistance can be enhanced. This is of particular importance since recent years experience dynamic development of ecological and integrated plant production with an emphasis on plant biotic stress resistance. Highly resistant genetic resources have not been reported in Brassica cultivated species, although some varieties differ in their resistance/susceptibility level. Strong cross-incompatibility, polygenic background of the resistance (additive and dominant gene interactions), as well as the differences in ploidy between the Brassica species of interest, render the transfer of Alternaria resistance from the wild species into the cultivated forms difficult. Additionally, it is often connected with employment of in vitro hybridization techniques, including somatic hybridization, embryo and ovary rescue, or protoplast fusion.

Shoot regeneration and free-radical scavenging activity in Silybum marianum L.

The morphogenic potential and free-radical scavenging activity of the medicinal plant, Silybum marianum L. (milk thistle) were investigated. Callus development and shoot organogenesis were induced from leaf explants of wild-grown plants incubated on media supplemented with different plant growth regulators (PGRs). The highest frequency of callus induction was observed on explants incubated on Murashige and Skoog (MS) medium supplemented with 5.0 mg l−1 6-benzyladenine (BA) after 20 days of culture. Subsequent transfer of callogenic explants onto MS medium supplemented with 2.0 mg l−1 gibberellic acid (GA3) and 1.0 mg l−1 α-naphthaleneacetic acid (NAA) resulted in 25.5 ± 2.0 shoots per culture flask after 30 days following culture. Moreover, when shoots were transferred to an elongation medium, the longest shoots were observed on MS medium supplemented with 0.5 mg l−1 BA and 1.0 mg l−1 NAA, and these shoots were rooted on a PGR-free MS basal medium. Assay of antioxidant activity of in vitro and in vivo grown tissues revealed that significantly higher antioxidant activity was observed in callus than all other regenerated tissues and wild-grown plants.

Positive correlations between hypericin and putative precursors detected in the quantitative secondary metabolite spectrum of Hypericum

A spectrum of eight pharmacologically important secondary compounds, all putatively belonging to the polyketide pathway (hypericin, pseudohypericin, emodin, hyperforin, hyperoside, rutin, quercetin, and quercitrin) were analyzed in several hypericin-producing species of Hypericum by LC–MS/MS. Different organs such as leaves, stems and roots of wild-grown plants of Hypericum hirsutum L., Hypericum maculatum Crantz s. l., Hypericum montanum L., Hypericum tetrapterum Fr. collected in Slovakia and of Hypericum perforatum L. collected in India were examined individually. Highest contents of hypericin, pseudohypericin, and emodin were found in H. montanum, suggesting that there are alternative species to H. perforatum with high pharmaceutical value. Amounts of hyperforin and quercetin were highest in H. perforatum, whereas highest contents of hyperoside and quercitrin were found in H. maculatum. A significant positive correlation between hypericin and pseudohypericin as well as between hypericin and emodin was observed by Kruskal’s multidimensional scaling (MDS), indicating a parallel enhancement of emodin as a common precursor in the biosynthetic pathways of hypericin and pseudohypericin. Furthermore, MDS combined with principal component analysis (PCA) revealed strong correlations in the occurrence of pseudohypericin and emodin, pseudohypericin and quercitrin, hypericin and quercitrin, emodin and quercitrin, hyperoside and quercitrin, rutin and quercetin, and, hyperforin and quercetin. On the other hand, rutin showed a negative correlation with emodin as well as with quercitrin. Furthermore, hierarchical agglomerative cluster analysis (HACA) clustered hypericin and pseudohypericin, grouping emodin at equal distance from both. Considerable infraspecific variability in secondary compound spectrum and load of different populations of H. maculatum from Slovakia underscores the need for detailed studies of genotypic variation and environmental factors in relation to polyketide biosynthesis and accumulation.

LC‐MS analysis of 13,28‐epoxy‐oleanane saponins in Maesa spp. extracts with antileishmanial activity

Saponins are natural products that are well known for a wide range of biological activities. For saponins of Maesa balansae, selective antileishmanial activity has been described. In view of their pharmacological interest, several Maesa species from the National Botanical Garden of Meise (Belgium) and wild-grown plants from Vietnam were screened for their antileishmanial potential and saponin content. Different parts of the plants (mainly leaves and twigs) were collected, dried and extracted. Plant extracts were evaluated by liquid chromatography/mass spectrometry (LC-MS) using electrospray ionisation in the negative ion mode and their saponin content was compared with those of Maesa balansae (maesabalides) and Maesa lanceolata (maesasaponins). Several Maesa species (M. ambigua, M. argentea, M. brevipaniculata, M. japonica and M. perlarius) showed potent antileishmanial activity (<0.1 microg/mL) and indeed contained known maesasaponins and maesabalides. However the leaves of M. argentea also revealed two new compounds. Two saponins with [M - H]- ions at m/z 1465 and 1477 were characterised. Their mass spectrometric fragmentation pattern revealed a structure that was the same or closely related to maesasaponin V.3 and VI.2, respectively, but had a glycan part with one additional hexose residue. Several known as well as new saponins from Maesa species active against leishmaniasis were characterised using LC-MS.

Chemical Composition of the Essential Oils from Cultivated and Wild Grown St. John's Wort (Hypericum perforatum)

The GC, GC/MS analysis revealed more than 80 individual components in the volatile fractions of St. John's Wort (Hypericum perforatum L.) grown in Greece, from which 69 have been identifed. Germacrene D was the main component found in the hydrodistilled oils from wild-grown (22.8%) and cultivated plants (16.9%), respectively, followed by 2-methyloctane (10.8–17.8%), β-caryophyllene (6.6–10.3%), α-pinene (5.2–10.1%) and bicyclogermacrene (4.1–4.8%). Fourteen of the constituents characterized in the oils of wild-grown plants were not detected in the oils of cultivated plants.

An empirical test of partner choice mechanisms in a wild legume–rhizobium interaction

Mutualisms can be viewed as biological markets in which partners of different species exchange goods and services to their mutual benefit. Trade between partners with conflicting interests requires mechanisms to prevent exploitation. Partner choice theory proposes that individuals might foil exploiters by preferentially directing benefits to cooperative partners. Here, we test this theory in a wild legumerhizobium symbiosis. Rhizobial bacteria inhabit legume root nodules and convert atmospheric dinitrogen (N2) to a plant available form in exchange for photosynthates. Biological market theory suits this interaction because individual plants exchange resources with multiple rhizobia. Several authors have argued that microbial cooperation could be maintained if plants preferentially allocated resources to nodules harbouring cooperative rhizobial strains. It is well known that crop legumes nodulate non-fixing rhizobia, but allocate few resources to those nodules. However, this hypothesis has not been tested in wild legumes which encounter partners exhibiting natural, continuous variation in symbiotic benefit. Our greenhouse experiment with a wild legume, Lupinus arboreus, showed that although plants frequently hosted less cooperative strains, the nodules occupied by these strains were smaller. Our survey of wild-grown plants showed that larger nodules house more Bradyrhizobia, indicating that plants may prevent the spread of exploitation by favouring better cooperators.

Liquid culture system for shoot multiplication and secoiridoid production in micropropagated plants of Centaurium erythraea Rafn

An efficient shoot multiplication method from shoot tips of Centaurium erythraea using liquid Murashige and Skoog (MS) medium supplemented with indole-3-acetic acid (IAA) (0.1 mg l −1) and 6-benzylaminopurine (BAP) (1.0 mg l −1) was developed. Under these conditions, almost 60 microshoots per explant were produced within 4 weeks. This is three times more as compared to shoots obtained on agar-solidified medium. Shoots taken from liquid culture were rooted with frequency 85% and 77% on hormone-free full-strength and half-strength MS medium, respectively within 6 and 4 weeks. The plantlets were transferred into soil and they survived acclimatization with 90% success, producing healthy plants, morphologically similar to plants derived from shoots grown on solid culture during their multiplication stage. The shoots of 10-week-old micropropagated plants of C. erythraea accumulated secoiridoid glucosides (gentiopicroside, swertiamarin and sweroside) up to 149 mg g −1 dry weight. The value was significantly higher than those achieved for other tested plant materials, such as shoot cultures and aerial parts of wild-grown plants. It is hoped, that the system using liquid shoot culture could be useful for large-scale micropropagation of C. erythraea plants with high production of pharmacologically important products.

Bryophyllum pinnatum Kurz. – A NEW CUT FLOWER SPECIES. I. AESTHETIC VALUE

Flowers of succulent plants are seldom being used as cut flowers, although they were appreciated in the past. This report summarizes the results of a five years study conducted upon wild grown plants as weed. B. pinnatum (syn. Kalanchoe pinnata: common name: los botoncitos) flowering from December till March in the climatic conditions of the state of Puebla, México, forming beautiful groups in the rural landscape. From such stands samples were taken to evaluate the aesthetic value of the inflorescence under ordinary room conditions. Shoots with first flowers opened were used whenever possible. The following data were collected: total length of flowering stalk, length of lateral inflorescences, total initial and final fresh weight, number of lateral inflorescences, number of flowers opened and buds present at weakly intervals, dry weight of the inflorescence components at the end of the experiment (only 1999-2000). Plants giving inflorescences in the shadow or at greenhouse conditions produced greenish buds with fading red-brownish colors on both parts of the inflorescence. Inflorescences from sunny sites placed at room conditions, in few days started fading its red color. Inflorescences kept in water or in dry-vase produced constantly new opened flowers in both the southern and northern windows exposition. The collapse of stalk tissue was more pronounced when kept in dry vase. No collapse of peduncle tissue was noticed. The gradient of fresh mass at the and of experiment was: stalk > flowers > peduncles > opened flowers > closed flowers > calyx. Generaly, the vase life and the aesthetic appreciation were better when the inflorescences were kept in southern exposition.

DRYING OF MEDICINAL PLANTS WITH SOLAR ENERGY UTILISATION

ABSTRACT In the paper, a potential of solar energy for drying of medicinal plants in Polish conditions is estimated and development of solar drying technologies is presented. The results of economic assessment of flat-plate solar collectors applied for drying of medicinal plants on a farm are promising. In some specific conditions, e.g. drying of wild grown medicinal plants in remote areas, even application of photovoltaic modules for driving of a fan of a solar dryer is a profitable option and enables easy control of the drying air temperature.

Germination of Seeds of Various Herbaceous Species under Leaf Canopy

The seeds of 100 herbaceous species were exposed for germination under the leaf canopy, giving great preponderance of far red radiation. The responses of various species differ greatly; the majority of them demonstrated more or less inhibition of germination, as compared with the diffuse white light control. An attempt was made to determine the relations between the degree of inhibition and various features of the examined species (together with the previously tested ones, their number was 130). The positive photoblastic seeds were always inhibited; among the indifferent and negative photoblastic seeds the inhibition was less frequent. There seems to be no relation between taxonomic position and occurence of inhibition. The inhibition of germination is much more frequent among wild-grown plants than among cultivated ones. Almost all the wild plants of open habitats showed strong inhibition; the common weeds of cultivated areas demonstrated more diversity.