Plant Biology

Three grasses (Poaceae) of different C 4 subtypes, Paspalum dilatatum (NADP-malic enzyme [ME]), Cynodon dactylon (NAD-ME) and Zoysia japonica (phosphoenolpyruvate carboxykinase), occur in natural habitats that differ in annual rainfall. Their leaf characteristics were studied to identify traits related to drought tolerance. Plants were grown in pots, and water defi cit was gradually induced by withholding water. Leaves of Z. japonica had the greatest and P. dilatatum the lowest relative dry matter content. Transverse sections of leaves that developed during the water defi cit showed little change compared to control leaves, consistent with low phenotypic plasticity. Anatomical features distinguished the three species, with xeromorphic characteristics most strongly represented in Z. japonica . The leaf relative water content (RWC) decreased with the soil water content similarly for the three grasses. However, at 80% RWC, the leaf water potential was − 3.1 MPa for Z. japonica and only − 1.3 MPa for P. dilatatum and C. dactylon . Soluble amino acids, especially proline, increased as RWC decreased in leaves of C. dactylon and Z. japonica . Phenylalanine, valine, leucine, and isoleucine increased more in Z. japonica than in the other two species. The results provide evidence that C. dactylon and, especially, Z. japonica have evolved leaf traits better suited to arid habitats.

Scilla maderensis Menezes (Hyacinthaceae) is endemic to the Portuguese Archipelago of Madeira. The taxonomic proximity between Scilla L. and Urginea Steinh. genus, and also the knowledge that bulbs of Urginea maritima (L.) Baker (Scilla maritima L.) contain cardiac glycosides of the bufadienolide type, led us to a phytochemical and pharmacological study of S. maderensis. Extracts obtained from the bulbs were screened by TLC and tested in the isolated frog heart preparation. The TLC screening revealed spots with colours and R f values similar to those obtained for proscillaridin and scillaren A. In the frog heart preparation the extracts showed a positive inotropic effect and toxic doses induced the arrest of the heartbeat in systole. We can conclude that the bulbs of S. maderensis contain substances exerting pharmacological effects on the heart.

The endemic Hawaiian genus Brighamia (Campanulaceae) comprises two federally endangered, morphologically similar species, B. insignis from Kaua'i and Ni'ihau and B. rockii from Moloka'i. To assist the design of conservation management programs for these taxa, isozyme analyses were performed to assess the levels of genetic diversity at the population and species levels, including comparisons within and among seven natural populations and one ex situ collection each of B. insignis and B. rockii. Our sampling (N ϭ 80) represents ϳ41% of all known individuals in the wild. Isozyme analyses revealed levels of genetic variation comparable to those reported for other Hawaiian flowering plant taxa but low levels of genetic variation at the population and species levels when compared to flowering plants in general. Ex situ individuals (N ϭ 61) were genetically representative of natural populations and hence may appropriately serve as stock for population augmentations. The two morphologically similar Brighamia species were highly distinct genetically. The combination of morphological and ecological similarity with allozymic dissimilarity observed in Brighamia is unique among the Hawaiian taxa studied to date.

Ceramium tenuicorne (Kützing) Waern is a red alga that is widely distributed in the brackish Baltic Sea. We studied the growth response of Ceramium to low salinity and nutrient enrichment, using isolades from two regions of the Baltic Sea where the alga approaches its inner distribution limit. Ecotypic differentiation was observed in that differences in growth response among isolates corresponded to salinity conditions in their regions of origin. Isolates from the Gulf of Bothnia (4 psu) had inherently lower growth rates that were not increased when transferred to higher salinity, but were better adapted to very low salinity levels than isolates from the Baltic Proper (7 psu). Further, the results indicate that Ceramium from different regions of the Baltic Sea vary in their responses to nutrient enrichment. The observed differences may be best described as a quantitative difference in the proportion of isolates with hyposaline adaptation. The results indicate that the wide distribution of Ceramium in the Baltic Sea is better explained by the occurrence of locally adapted genotypes than by a generalist life strategy, and provide example of adaptive differentiation in a marine edge environment.

Symptoms of decline have been observed on dying coast live oak (Quercus agrifolia) trees in areas throughout southern California that are both infested and uninfested by the gold-spotted oak borer (GSOB). The purpose of this study was to identify and assess the pathogenicity of several anamorph species of the Botryosphaeriaceae, including Diplodia corticola, Dothiorella iberica and Diplodia agrifolia sp. nov., that were recovered consistently from symptomatic tissues. Species were identified morphologically and by phylogenetic analyses of the complete sequence of the internal transcribed spacer (ITS) of the rDNA and partial sequences of b-tubulin and elongation factor (EF1-a) genes. Results from morphological assessments and phylogenetic analyses support the erection of a new species closely related to D. mutila, described herein as Diplodia agrifolia sp. nov. Pathogenicity of all species was verified by wound inoculation of 1 y old coast live oak seedlings under controlled conditions. Isolates of D. corticola were the most aggressive tested, and isolates of D. agrifolia were the second most aggressive. Both species caused bleeding symptoms on inoculated seedlings. Seedlings inoculated with D. corticola died within 4 wk, with the pathogen progressing up and down through the xylem in advance of living phloem and moving throughout the taproot in 70% of inoculated seedlings. Colonization and re-isolation was successful for all species. All three fungal species represent newly recorded fungal pathogens of coast live oak in California. Results from the pathogenicity test suggest that these fungi play a role in the decline of coast live oaks throughout southern California.

Conventional methods to detect and assess the viability of plant pathogenic bacteria are usually based on plating assays or serological techniques. Plating assays provide information about the number of viable cells, expressed as colony-forming units, but are time-consuming and laborious. Serological methods, such as the enzyme-linked immunosorbent assay (ELISA) and immunofluorescence microscopy (IF), can be performed in a shorter timespan than most plating assays, but they do not discriminate between live and dead cells. Flow cytometry (FCM) in combination with fluorescent probe technology is a rapid, sensitive, and quantitative technique to detect microorganisms and assess their viability. Quantitative information on the presence and viability of plant pathogenic microorganisms is valuable for risk assessment regarding disease transmission and disease development. FCM has been applied successfully in the fields of food microbiology, veterinary science, and medical research to dete...

Bacterial resistance to antibiotics continues to be a grave threat to human health. Because antibiotics are no longer a lucrative market for pharmaceutical companies, the development of new antibiotics has slowed to a crawl. The World Health Organization reported that the 8 new bacterial agents approved since July 2017 had limited clinical benefits. While a cohort of biopharmaceutical companies recently announced plans to develop 2-4 new antibiotics by 2030, we needn’t wait a decade to find innovative antibiotic candidates. Essential oils (EOs) have long been known as antibacterial agents with wide-ranging arsenals. Many are able to penetrate the bacterial membrane and may also be effective against bacterial defenses such as biofilms, efflux pumps, and quorum sensing. EOs have been documented to fight drug-resistant bacteria alone and/or combined with antibiotics. This review will summarize research showing the significant role of EOs as nonconventional regimens against the worldwid...

The antihyperglycemic and hypolipidemic activities of Hibiscus schizopetalus (Mast) Hook (Malvaceae) flower and leaves extracts were investigated in alloxan-induced diabetic rats. The hypoglycemic activity of both the extracts (100mg/kg, body weight) was tested in fasting normal rat, glucose loaded rats. Observation on body weight was also recorded. The extracts showed a significant (P<0.001) reduction in blood glucose level in normal fasting rats. In glucose tolerance test, significant (P<0.01) decreased observed in all glucose loaded animals. While in alloxan induced diabetic rats, the percent blood glucose reduction was 59.94% and 45.14% in extracts treated groups. The results obtained were compared with the reference standard drug Tolbutamide (100mg/kg, body weight). The diabetic rats showed sign of decreased in their body weight during the treatment period. Cholesterol and triglycerides levels were significantly decreased (P<0.001) by HFE. The results obtained demonstrated the potential hypoglycemic activity of methanolic extracts of H. schizopetalus. There is need of bioassay-directed assay of the active principles responsible for the anti-diabetic activity. The methanolic extracts showed the presence of carbohydrates, alkaloids, steroids, terpenes, saponins and glycosides.

A phylogeny based on nrITS1 and trnL-F sequences resolves the Lejeunea tumida species group polyphyletic with individuals belonging in two clades either side of the basal-most node within Lejeunea. It is impossible for the Lejeunea tumida species group to be more polyphyletic and still be attributed to the same genus under the existing generic classification. A simulation-based approach to testing the null hypothesis of group monophyly rejects this at the P < 0.01 level of significance. Bayesian tests find very strong support for polyphyly, given the data. The monophyly of L. tumida s.s. + L. colensoana is fully supported; however, although Lejeunea tumida s.s. is nested within L. colensoana, this position is not supported. Both L. oracola and L. rhigophila are resolved as monophyletic. Whereas there is moderate support for the monophyly of L. rhigophila, there is no support for the monophyly of L. oracola. Neither is the monophyly of L. oracola + L. rhigophila supported in Bayesian or parsimony analysis.

Ethnopharmacological relevance: Before modern anticonvulsive drugs were developed people in central Europe used herbal remedies to treat epilepsy. Hundreds of different plants for this indication can be found in German herbals of the 16th and 17th centuries. Here we compile these plants and discuss their use from a pharmacological perspective. Materials and methods: Nine of the most important European herbals of the 16th and 17th century including Bock (1577), Fuchs (1543), Mattioli (1590), Lonicerus (1660, 1770), Brunfels (1532), Zwinger (1696), and Tabernaemontanus (1591, 1678) were searched for terms related to epilepsy, and plants and recipes described for its treatment were documented. We then searched scientific literature for pharmacological evidence of their effectiveness. Additionally the overlapping of these remedies with those in De Materia Medica by the Greek physician Dioscorides was studied. Results: Two hundred twenty one plants were identified in the herbals to be used in the context of epilepsy. In vitro and/or in vivo pharmacological data somehow related to the indication epilepsy was found for less than 5% of these plants. Less than 7% of epilepsy remedies are in common with De Materia Medica. Conclusions: Numerous plants were used to treat epilepsy in the 16th and 17th centuries. However, few of these plants have been investigated with respect to pharmacological activity on epilepsy related targets.

Forty-five Brazilian populations of freshwater Audouinella were analysed using multivariate morphometrics. These populations were statistically related to seven type specimens. Five species are recognised on the basis of qualitative (plant colour and size, basal system type and branch angle) and quantitative (length and diameter of vegetative cells and monosporangia) characters. A. hermannii (syn. A. violacea) is characterised by a reddish colour, an irregular prostrate basal system, open branch angles (~ 25 °) and small monosporangia (G 15 #m in diameter). A. macroepora (syn. A. chalybea var. brasiliensis) is distinguished from the other Brazilian species by having a bluish colour, a basal system composed of well-developed rhizoids, narrow branch angles ( < 25°) and large monosporangia (~ 15 #m in diameter). A. meiospora is microscopic and has a reddish colour, a basal system composed of creeping filaments, narrow branch angles and small monosporangia. A. pygmaea (syn. A. leibleinii) is characterised by being bluish, having an irregular prostrate basal system, narrow branch angles and small monosporangia. A. tend& is distinct from the other species by having a reddish colour, an irregular prostrate basal system, open branch angles, small monosporangia and small vegetative cells (G 6 #m in diameter). An identification key and revised descriptions and synonyms are presented for the five species. A. meiospora and A, tenella are reported for the first time for Brazil. A. macrospora and A. pygmaea were the most widespread species and occurred in tropical and subtropical regions. A. meiospora was found at two sites in a tropical rainforest region, whereas A. hermannii and A. tenella were found at only one site. Selected physical and chemical environmental data (temperature, specific conductance, current velocity, turbidity, pH and dissolved oxygen) are presented for most species.

Bixa orellana L. (Bixaceae) seed extract, used in Africa as a dye, was employed to evaluate the onset of the possible topical localized responses of the rabbit skin in single application, after repeated application and after UV exposure. Histologic studies were also carried out to evaluate the possible damage and penetration of Bixa colouring matter into the rabbit hairless skin and into the hairs. The study showed that Bixa orellana has a good cutaneous tolerability and may encourage the use as a source of colouring matter in cosmetology.

Earlier descriptions of the Indo-Pacific red alga Portieria hornemannii lacked detailed information on its vegetative and reproductive development and morphology. An in-depth treatment is presented on the development of the uniaxial thallus and the formation of male, female and tetrasporangial nemathecia. Post fertilization events and carposporophyte development is described, confirming Kylin's presumption on the development of connecting filaments between the carpogonium and the auxiliary cell following fertilization. Phylogenetic analysis using chloroplast encoded rbcL and nuclear ribosomal LSU gene sequences, including members of Rhizophyllidaceae and their close relatives suggests a monophyletic family. Contarinia is resolved as the sister taxon of a clade uniting Nesophila, Ochtodes and Portieria. The relationships among the latter genera remain largely unresolved.

Six cunaxid species of three known genera, including one new species are reported for the first time from Iran. The known species are Coleobonzia saaymani , Coleoscirus simplex ), Coleoscirus buartsus Den Heyer, 1980b, Coleoscirus breslauensis Den Heyer, 1980b and Coleoscirus tuberculatus Den Heyer, 1978. The new species, Neoscirula sepasgosariani, is described and illustrated. A key for the Iranian Coleoscirinae is given.

Callus induction from petiole explants has been achieved in Alocasia micholitziana `Green Velvet'. The highest percentage (71%) of explants inducing callus was obtained on MS medium supplemented with 0.5 μM 2,4-D and 0.5 μM kinetin in the dark after 4 months of culture. Shoots were regenerated at the highest frequency of 33.3% under light condition when 0.5 μM BA was added to MS medium with the average of 7.8±2.3 shoots per callus explant. The callus-derived shoots rooted on hormone free MS medium and within 4 weeks the plantlets were ready for acclimatization. The regenerated plants appeared morphologically similar to mother plants.

Ethnopharmacological relevance: In particular five polypore species, i.e. Laetiporus sulphureus, Fomes fomentarius, Fomitopsis pinicola, Piptoporus betulinus, and Laricifomes officinalis, have been widely used in central European folk medicines for the treatment of various diseases, e.g. dysmenorrhoea, haemorrhoids, bladder disorders, pyretic diseases, treatment of coughs, cancer, and rheumatism. Prehistoric artefacts going back to over 5000 years underline the long tradition of using polypores for various applications ranging from food or tinder material to medicinal-spiritual uses as witnessed by two polypore species found among items of Ötzi, the Iceman. The present paper reviews the traditional uses, phytochemistry, and biological activity of the five mentioned polypores. Materials and methods: All available information on the selected polypore taxa used in traditional folk medicine was collected through evaluation of literature in libraries and searches in online databases using SciFinder and Web of Knowledge. Results: Mycochemical studies report the presence of many primary (e.g. polysaccharides) and secondary metabolites (e.g. triterpenes). Crude extracts and isolated compounds show a wide spectrum of biological properties, such as anti-inflammatory, cytotoxic, and antimicrobial activities. Conclusions: The investigated polypores possess a longstanding ethnomycological tradition in Europe. Here, we compile biological results which highlight their therapeutic value. Moreover, this work provides a solid base for further investigations on a molecular level, both compound-and target-wise.

Plants are fundamentally important to life. Key research areas in plant science include plant species identification, weed classification using hyper spectral images, monitoring plant health and tracing leaf growth, and the semantic interpretation of leaf information. Botanists easily identify plant species by discriminating between the shape of the leaf, tip, base, leaf margin and leaf vein, as well as the texture of the leaf and the arrangement of leaflets of compound leaves. Because of the increasing demand for experts and calls for biodiversity, there is a need for intelligent systems that recognize and characterize leaves so as to scrutinize a particular species, the diseases that affect them, the pattern of leaf growth, and so on. We review several image processing methods in the feature extraction of leaves, given that feature extraction is a crucial technique in computer vision. As computers cannot comprehend images, they are required to be converted into features by individually analyzing image shapes, colors, textures and moments. Images that look the same may deviate in terms of geometric and photometric variations. In our study, we also discuss certain machine learning classifiers for an analysis of different species of leaves.

Your article is protected by copyright and all rights are held exclusively by KNPV. This eoffprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".

Since the discovery of topolins as naturally occurring aromatic cytokinins (CKs), they have emerged as genuine alternatives to the long serving CKs such as benzyladenine, zeatin and kinetin in plant tissue culture (PTC). Globally, the past 15 years has witnessed a surge in the use of topolins and their derivatives in research laboratories. Topolins, especially the meta-topolin and its derivatives have been employed for culture initiation, protocol optimization and for counteracting various in vitro induced physiological disorders in many species. Evidence from various studies indicate the rising popularity and advantages (although not universal for all species) of topolins compared to other CKs. In this review, we assess the use of topolins in PTC with emphasis on their metabolism, structure-activity relations and effect on morphogenesis in vitro. In addition, the review provides a detailed list of species that have been used to study the effect of topolins in comparison with other CKs, the growth parameters affected and recommended concentrations are also provided.

We studied the breeding systems of four populations of Enterolobium cyclocarpum (guanacaste, earpod tree) in Costa Rica. Multilocus estimates of the outcrossing rate indicate that E. cyclocarpum is a predominant outcrossing species (t m ranged between 0.881 and 0.901) and biparental inbreeding is low (range between 0.058 and 0.079). Overall, our analyses showed significant differences in the gene frequencies between pollen and ovules and significant differences in pollen gene frequencies between the four populations. We also found significant differences in the pollen gene frequencies calculated for single trees in the same population. Outcrossing rates and pollen gene frequencies varied in two consecutive years in two populations of E. cyclocarpum. The correlated mating model revealed that there are differences in the correlation of paternity between populations and years. These findings indicate that there is variation in the average number of trees that father the seed crop of each tree and/or that some fathers are overrepresented in the seed crop of each tree. The implication of these findings for the development of strategies for conservation and management of this species are discussed.

Capparis decidua (Forsk.) is belonging to family Capparidaceae, yet important medicinal plant of Indian Medicinal Plants. In the traditional system of medicine, the bark has been shown to be useful in the treatment of coughs, asthma and inflammation; roots used in fever and buds in the treatment of boils. In Unani, leaves act as appetizer, helps in cardiac troubles, fruits used in biliousness. The plant is reported to contain Phytochemicals including alkaloids, terpenoids, glycosides and some fatty acids. In Unani, leaves act as appetizer, helps in cardiac troubles, used in biliousness; alveolaris and pyorrhea; Root bark is used as anthelmintic and purgative. The plant have significant pharmacological activities like hypercholesterolemic, anti-inflammatory and analgesic, antidiabeti, antimicrobial, antiplaque, antihypertensive, antihelmintic & purgativ activities. The review analyses phytochemical and pharmacological potential of medicinal plant (kair).

Agarwood is a valuable oleoresin obtained from wounded tree of various genus of Thymelaeaceae family especially from Aquilaria species. Agarwood is regarded as most treasured non-timber forest product used in fragrances as well as medicines. Quality of agarwood plays an important role to define its commercial value. Different countries use different grading pattern to define the quality of agarwood. More than 250 compounds have been identified so far, mostly sesquiterpenoids, chromones and volatile aromatic compounds. GC-MS is the considered as a best method for the identification of chemical profile of the agarwood by various authors. Present review discusses the various methods used to determine quality of agarwood and chemical constituents of infected agarwood tree.

Plant-derived compounds are regarded as a substantial source for novel lead structures to develop medicines and biocides natural products. Concurrent with greater awareness towards the use of synthetic chemicals in agricultural practice, the application of integrated pest management programs has also increased. In recent years, there has been considerable public pressure to reduce the use of synthetic fungicides in agriculture. Although, the use of synthetic fungicides in plant disease control has been successful in improving agricultural output, several of these have been found to exhibit sideeffects in the form of carcinogenicity, detrimental effects and other residual toxicities. The alternative choice therefore would be the use of botanical fungicides, which are found to be largely nonphytotoxic, systematic and easily biodegradable in nature. The present study is a summary of review literature during past decades which focused on bioactive compounds isolated from plants against plant pathogenic fungi.

Globally, harmful algal blooms (HABs) caused by marine phytoplankton pose a significant threat to human health and result in enormous economic loss. Many strategies have been implemented for their detection, management, and control. One such instrument is the red-tide acoustic sensing system (RASS) which utilizes a backscattered acoustic signal to detect microalgal cells in the water column, proving to be a cheap and easy tool for the HABs detection. In the current study, five RASSs were deployed at fish farms located in HAB-occurring areas of South Korea during the summer of 2018, and their performance examined for the HABs detection. From 26 July to 6 August 2018, the dinoflagellate Cochlodinium polykrikoides was the most abundant HAB species across all locations. A standard curve between the relative received level (RRL) of acoustic intensity as measured by RASS and cell densities of HAB species was constructed (R 2 = 0.846) and was successfully applied to quantify the HAB cell density. The RRL values noticeably increased from July 25, 2018 and decreased from August 1. The RRL values corresponding to warning level of HABs (≥ 100 cells mL −1) were not measured after August 5. The highest 22 RRL was recorded on July 29, which corresponded to 2,782 cells mL −1. To evaluate the efficacy and accuracy of the RASS, a significant correlation (R 2 = 0.997) between HAB cell abundance and backscattered acoustic signals was confirmed. Results from our study show that the RASS can produce accurate, real-time bloom data, providing significant advantages for the warning of HABs.

Perennial biofuel crops such as Miscanthus and switchgrass are thought to increase soil organic matter and therefore may increase soil nitrogen (N) mineralization rates. Our objective was to evaluate a range of N-mineralization indices for soils with established biofuel crops and compare these results with soils in a traditional corn and soybean rotation. We sampled surface soil (0-10 cm deep) from switchgrass (6 years after establishment) and Miscanthus plots (5 years) in a high-organic-matter Mollisol. The longest potential N mineralization index, a 24-day incubation, was significantly greater in Miscanthus soils compared to switchgrass and corn-soybean. In addition, 7-day anaerobic N and potassium chloride-extractable ammonium N were both greater in Miscanthus soils compared to switchgrass and corn-soybean. Our results do support our hypothesis that N-mineralization rates are greater in soils under biofuel production.

Plants deploy a finely tuned balance between growth and defence responses for better fitness. Crosstalk between defence signalling hormones such as salicylic acid (SA) and jasmonates (JAs) as well as growth regulators plays a significant role in mediating the trade-off between growth and defence in plants. Here, we specifically discuss how the mutual antagonism between the signalling of auxin and SA impacts on plant growth and defence. Furthermore, the synergism between auxin and JA benefits a class of plant pathogens. JA signalling also poses growth cuts through auxin. We discuss how the effect of cytokinins (CKs) is multifaceted and is effective against a broad range of pathogens in mediating immunity. The synergism between CKs and SA promotes defence against biotrophs. Reciprocally, SA inhibits CK-mediated growth responses. Recent reports show that CKs promote JA responses; however, in a feedback loop, JA suppresses CK responses. We also highlight crosstalk between auxin and CKs ...

A typical character of plants is the production and storage of usually complex mixtures of secondary metabolites (SM). The main function of secondary metabolites is defense against herbivores and microbes; some SM are signal compounds to attract pollinating and seed dispersing animals or play a role in the symbiotic relationships with plants and microbes. The distribution of SM in the plant kingdom shows an interesting pattern. A specific SM is often confined to a particular systematic unit, but isolated occurrences can occur in widely unrelated taxonomic groups. This review tries to explain the patchy occurrence of SM in plants. It could be due to convergent evolution, but evidence is provided that the genes that encode the biosynthesis of SM appear to have a much wider distribution than the actual secondary metabolite. It seems to be rather a matter of differential gene regulation whether a pathway is active and expressed in a given taxonomic unit or not. It is speculated that the...

The cloning of the jellyfish gfp (green fluorescent protein) gene and its alteration for expression in subcellular locations in transformed plant cells have resulted in new views of intracellular organization and dynamics. Fusions of GFP with entire proteins of known or unknown function have shown where the proteins are located and whether the proteins move from one compartment to another. GFP and variants with different spectral properties have been deliberately targeted to separate compartments to determine their size, shape, mobility, and dynamic changes during development or environmental response. Fluorescence Resonance Energy Transfer (FRET) between GFP variants can discern proteinu protein interactions. GFP has been used as a sensor to detect changes or differences in calcium, pH, voltage, metal, and enzyme activity. Photobleaching and photoactivation of GFP as well as fluorescence correlation spectroscopy can measure rates of diffusion and movement of GFP within or between compartments. This review covers past applications of these methods as well as promising developments in GFP imaging for understanding the functional organization of plant cells.

Folk medicine practitioners in Peril employ plant preparations as wound-healing agents on superficial and internal wounds (gastric ulcers). The results of a scientific evaluation of the wound-healing activity of nine plants found in the Amazon jungle near Iquitos and in the Andes mountains is presented. The species studied were: Peperomia galioides, Mentzelia cordifolia, Mutisia acuminata, Himatanthus sucuuba, Spondias mombin, Eleutherine bu[bosa, Muehlenbeckia tamnifolia, Anredera diffusa and Jatropha curcas. These plants have also been examined for their toxicological properties, their effect on blood pressure, smooth muscle and capillary permeability. Significant wound-healing activity was detected in Peperomia galioides, Anredera diffusa and Jatropha curcas. Extracts from Peperomia galioides and Anredera diffusa had no effect on cell proliferation and did not exhibit mutagenic activity.

The R gene family determines the timing, distribution and amount of anthocyanin pigmentation in maize. This family comprises a set of regulatory genes, consisting of a cluster of several elements at the R locus, on chromosome 10, the Lc and Sn gene lying about two units Rdistal and 8 o n chromosome 2. Each gene determines a tissue-specific pigmentation of different parts of the seed and plant. The proposed duplicated function of R, Sn, Lc and B loci is reflected in cDNA sequence similarity. In this paper an extensive analysis of the predicted proteins of the R, Sn, Lc and B genes together with a search for putative sites of post-translational modification is reported. A comparison with the PROSITE database discloses several Nglycosylation and phosphorylation sites, as well as the basic Helix-Loop-Helix (HLH) domain of transcriptional activators. Sn, Lc, and R S show a high conservation of these sites, while B is more divergent. Analysis of the 5' leader of mRNA sequences discloses the presence of five ATG triplets with two upstream open reading frames (uORFs) of 38 and 15 amino acids and a loop structure indicating a possible mechanism of control at the translational level. It is conceivable that possible mechanisms acting at the translational and post-translational level could modulate the expression and the activation of these transcription factors. Northern analysis of various tissues of different R alleles highlights a strict correlation between pigment accumulation in different tissues and the expression of the regulatory and structural genes suggesting that the pattern of pigmentation relies on a mechanism of differential expression of the members of the Rfamily. Analysis of the Sn promoter discloses the presence of several sequences resembling binding sites of known transcription factors (as GAGA and GT) that might be responsible for the spatial and light-induced expression

Jaborandi (Pilocarpus sp.;) is a shrub or small tree 3-7.5 m tall that can be found in native stands or as isolated individuals throughout Brazil. The leaves of jaborandi contain the alkaloid pilocarpine, widely used in ophthalmology for treatment of certain types of glaucoma and more recently for xerostomia. This paper discusses the current systems of production of jaborandi leaves in Maranhao, Northeastern Brazil. On one side, the extractivism practiced by indigenous people and peasants; on the other, the plantation recently established, as the result of heavy investment by a pharmaceutical company. In the extractive system, the non-sustainable exploitation of the drug-rich leaves of this plant species may have produced considerable damage to the native populations over time, reducing the size of the populations, and impoverishing their gene pools. The following potential effects of the plantation are discussed; contribute to diminishing the pressure on wild populations; impact on the local people currently involved in the extractivism; and its impacts on the local economies. Jaborandi (Pilocarpus sp., Rutaceae): Uma Esp6cie Nativa e Sua Rfipida Transforma~o em Cultura. Jaborandi (Pilocarpus sp.) ~ um arbusto ou arvoreta de 3-7.5 m de altura, que pode ser encontrado em formaf6es nativas ou como indfviduos isolados em vdrias partes do Brazil. As folhas do jaborandi cont~m o alcal6ide pilocarpina, largamente utilizado em oftalmologia, no tratamento de certos tipos de glaucoma. Este trabalho mostra vdrios aspectos dos atuais sistemas de produfao de folhas de jaborandi no Maranh~o, Nordeste do Brasil. De um lado, o sistema extrativista praticado por comunidades indigenas e camponeses; do outro, a plan-tagSo, recentemente implantada como resultado de significativo investimento por parte de uma industria farmac~utica, buscando domesticaf~o desta esp~cie nativa. No sistema extrativista, a explorag8o extrativa das folhas de jaborandi pode estar produzindo danos considertiveis its populaf6es nativas, reduzindo o tamanho dessas populag6es e empobrecendo suas bases gen(ticas. A plantafao, por outro lado, levanta quest6es em relafao ~ sua contribuifao para diminuir a pressao sobre as populagSes nativas, sobre o futuro do povo atualmente envolvido no extrativismo, e os seus efeitos na economia local.

We describe two newly discovered fungi living on the adaxial leaf surface of plants belonging to the Convolvulaceae, Ipomoea asarifolia and Turbina corymbosa. The fungi apparently are epibionts because hyphae were never observed to penetrate epidermal cells or stomata of their respective host plants, and most remarkably are intimately associated with secretory glands on the leaf surface. Hyphae and structures resembling chlamydospores and synnemata (but lacking conidia), formed by both fungal species are phenotypically nearly indistinguishable after in vitro growth or when examined in vivo on the leaf surface. Phylogenetic trees based on aligned DNA sequences from nuclear genes for b-tubulin (tubB) and RNA Polymerase II subunit 1 (rpbA), and the mitochondrial gene for ATP synthase F0 subunit A (atp6), grouped the fungal species in a clade within the Clavicipitaceae. Clavicipitaceous fungi isolated from the two different plant species could be distinguished by their atp6 and rpbA sequences, and nuclear genes for c-actin (actG), translation elongation factor 1-a (tefA), and 4-(c,c-dimethylallyl)tryptophan synthase (dmaW), the determinant step in ergoline (i.e. ergot) alkaloid biosynthesis. Based on these findings we propose a new fungal genus, Periglandula, gen. nov., and describe two new species, Periglandula ipomoeae sp. nov., from host plant I. asarifolia, and Periglandula turbinae sp. nov., from T. corymbosa.

Photon flux density (PFD) and water availability, the daily and seasonal factors that vary most in tropical environments, were examined to see how they influenced expression of crassulacean acid metabolism (CAM) in 3year-old Clusia shrubs native to Panama. Instead of the commonly used single-leaf approach, diel CO 2 exchange was measured for whole individual canopies of plants in large soil containers inside a naturally illuminated 8.8 m 3 chamber. In well-watered C. rosea, a mainly constitutive CAM species, nocturnally fixed CO 2 contributed about 50% to 24 h carbon gain on sunny days but the contribution decreased to zero following overcast days. Nonetheless, CO 2 fixation in the light responded in such a way that 24 h carbon gain was largely conserved across the range of daily PFDs. The response of C. rosea to drought was similarly buffered. A facultative component of CAM expression led to reversible increases in nocturnal carbon gain that offset drought-induced reductions of CO 2 fixation in the light. Clusia cylindrica was a C 3 plant when well-watered but exhibited CAM when subjected to water stress. The induction of CAM was fully reversible upon rewatering. C. cylindrica joins C. pratensis as the most unambiguous facultative CAM species reported in the genus Clusia.

Gouania longipetala is commonly used in Cameroonian traditional medicine to manage women fertility and menopausal complaints. However, despite this use, the estrogenic properties of Gouania longipetala (G. longipetala) have not been studied until now. The present study was aimed to assess estrogenic activities of the stem bark aqueous (GLA) and ethanolic (GLE) extracts of G. longipetala in post menopause-like model of ovariectomized (Ovx) Wistar rats. Animals were either sham-operated or Ovx. 84 days after ovariectomy, animals were divided into seven groups of five animals and were daily treated for 28 days with distilled water (10mL/kg) for group 1, 2% solution of Tween 80 (10mL/kg) for group 2, estradiol valerate (1mg/kg) for group 3, GLA (45 or 180mg/kg) and GLE (40 or 160mg/kg) for groups 4 to 7 respectively. Sham-operated animals daily received distilled water (10mL/kg). During the experimental period, the body weight was registered every week. At the day 29, blood pressure was registered by invasive method while uterine and vagina morphometry as well as body, uterine and abdominal fat weights changes were analyzed. Serum levels of total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol were determined. Moreover, oxidative stress markers such as nitrites, reduced glutathione (GSH) and malondialdehyde (MDA) were measured in homogenized liver and aorta. Compared with the sham control, vagina and uterine dystrophy and elevated blood pressure were observed in Ovx rats treated with vehicles. Biochemical parameters showed a significant increase of total cholesterol, triglycerides, LDL-cholesterol and MDA as well as a significant decrease of nitrites and GSH in Ovx animals treated with vehicle as compared to sham group. GLA and GLE displayed estrogen-like effects on vagina and did not affect uterine wet weight and epithelial height compared with vehicle groups. Both extracts displayed anti-atherogenic properties by reducing AI, AIP and LDL-cholesterol level as compared to vehicles groups. GLA and GLE significantly prevented the increase of MDA induced by ovariectomy as compared to rats treated with vehicles. This study showed that GLA and GLE exhibited estrogenic effects by providing vaginal lubrication, by modulating blood pressure and improving lipid profile, oxidative status and endothelial function and may not have an undesirable influence on the endometrium in ovariectomized rats.

Ethnopharmacological relevance: The essential oil (EO) from Cymbopogon citratus (DC) Stapf is reported to have a wide range of biological activities and is widely used in traditional medicine as an infusion or decoction. However, despite this widely use, there are few controlled studies confirming its biological activity in central nervous system. Materials and methods: The anxiolytic-like activity of the EO was investigated in light/dark box (LDB) and marble-burying test (MBT) and the antidepressant activity was investigated in forced-swimming test (FST) in mice. Flumazenil, a competitive antagonist of benzodiazepine binding and the selective 5-HT 1A receptor antagonist WAY100635 was used in experimental procedures to determine the action mechanism of EO. To exclude any false positive results in experimental procedures, mice were submitted to the rota-rod test. We also quantified some neurotransmitters at specific brain regions after EO oral acute treatment. Results: The present work found anxiolytic-like activity of the EO at the dose of 10 mg/kg in a LDB. Flumazenil, but not WAY100635, was able to reverse the effect of the EO in the LDB, indicating that the EO activity occurs via the GABA A receptor-benzodiazepine complex. Only at higher doses did the EO potentiate diethyl-ether-induced sleeping time in mice. In the FST and MBT, EO showed no effect. Finally, the increase in time spent in the light chamber, demonstrated by concomitant treatment with ineffective doses of diazepam (DZP) and the EO, revealed a synergistic effect of the two compounds. The lack of activity after long-term treatment in the LDB test might be related to tolerance induction, even in the DZP-treated group. Furthermore, there were no significant differences between groups after either acute or repeated treatments with the EO in the rota-rod test. Neurochemical evaluation showed no amendments in neurotransmitter levels evaluated in cortex, striatum, pons, and hypothalamus. Conclusions: The results corroborate the use of Cymbopogon citratus in folk medicine and suggest that the anxiolytic-like effect of its EO is mediated by the GABA A receptor-benzodiazepine complex.

The paper describes studies of post-fire succession in heathland vegetation in N.E. Scotland, dominated by Calluna vulgaris. A preliminary model (Legg, 1978) suggested good agreement between simulation of succession on the basis ofa Markov chain and observations of stands at different stages of development after burning, at least in the earlier stages. Vegetation transitions are currently being recorded in permanent plots on burnt areas. First results confirm the view that (a) the post-fire succession has the properties ofa Markov process, (b) this type of model remains valid when constructed from records of actual transitions, rather than data obtained by inference from evidence of transition. Comparing successional events in stands where, at the time of burning, the Calluna population was in pioneer-, building-, mature-and degenerate phases, shows that transition matrices generally agree with the Markov hypothesis, but not in the case of stands where Calluna was degenerate when burnt. The composition of establishing vegetation ! year after fire is not confined to species normally associated with the early stages of succession, but reflects the composition of the stand before burning. Redevelopment after fire is described in terms of an initial floristic composition of species with strategies permitting early re-establishment, selected by the recurrence of the fire factor. Subsequent transitions represent changes in their relative abundance due to differing growth properties and competitive interactions. This interpretation applies only under conditions of recurrent incidence of fire (normally once in 10-15 yr). If fire does not recur, Calluna stands pass into the degenerate phase, where changes in the nature of relay floristics may come into play (e.g. with tree colonization).

Weeds reduce crop productivity through competion for nutrients, water, light and space, and impact negatively on commercial crops. Honeybush tea (Cyclopia spp.) is an industry mainly focused on the organic cultivation of tea, using mechanical weeding control methods. To date, no studies have investigated the impact of weeds in honeybush plantations This study quantified the impact weeds have on honeybush plant survival, growth, yield, and economic value in order to identify a cost-effective and efficient integrated weed management system. Impacts of different weeding treatments were assessed at harvest on Cyclopia subternata Vogel 18 months after planting. The use of a synthetic woven mulch in combination with inter-row weeding resulted in significantly higher yield, larger plants, best growth rate and reduced weed biomass. Crop survival under this treatment was also greatly improved.

The biased amino acid composition and aperiodic (random coil) configuration of Group 1 late embryogenesisabundant (LEA) proteins imply that these proteins are capable of binding large amounts of water. While Group 1 LEAs have been predicted to contribute to osmotic stress protection in both embryonic and vegetative tissues, biochemical support has been lacking. We have used Saccharomyces cerevisiae as a model system to test the putative osmoprotective function of a wheat Group 1 LEA protein, Em. We demonstrate that expression of Em protein in yeast cells is not deleterious to growth in media of normal osmolarity and attenuates the growth inhibition normally observed in media of high osmolarity. Enhanced growth is observed in the presence of a variety of osmotically active compounds indicating that Em protein is capable of mitigating the detrimental effect of low water potential in a relatively non-specific manner. These results are the first biochemical demonstration of an osmoprotective function for a Group 1 LEA and suggest that the yeast expression system will be useful in dissecting the mechanism of protection through structure-function studies.