Ploidy dimorphism and reproductive biology in Stenodrepanum bergii (Leguminosae), a rare South American endemism.

This is the first report on chromosome numbers and the reproductive behaviour in Stenodrepanum Harms, a rare endemic and monotypic legume genus from the arid and salty areas of central-western Argentina. Sixty individuals belonging to two populations from two salty areas ("salinas") were surveyed and included mostly triploid (2n = 3x = 36) and only two diploid (2n = 2x = 24) plants. Meiosis in diploids is regular, with bivalent pairing and uniform and viable pollen. In contrast, meiosis in triploids is characterized by high trivalent pairing, with irregularly shaped pollen and variation in cytoplasm content and stainability, which is in agreement with an unbalanced segregation occurring in anaphases I and II. However, different triploid plants/individuals showed various degrees of pollen fertility, which may be attributed to particular genotypes. Research on reproductive biology events indicates sexual cross-pollinated reproduction enhanced by protogyny in both cytotypes. All plants produced seeds, but seedlings were only recovered from diploid plants pollinated with triploids, and even those eventually perished. Chromosome counts in these seedlings revealed aneuploid chromosome numbers owing to the combination of unbalanced gametes.

Intoxication of llamas by Astragalus punae in Argentina.

Several plants that contain indolizidine alkaloids, including swainsonine, are toxic to livestock, causing dysfunctional lysosomes and storage disease. Swainsonine induces a neurovisceral disease, known as locoism, in sheep, goats, and cattle, which occurs in several parts of the world, including, but not limited to, the western United States, China, and parts of Australia. In South America, locoism has been described in the Andean region of Argentina affecting sheep, cattle, and llamas. Intoxication by consumption of Astragalus punae was suspected in 4 llamas in Jujuy Province, northwestern Argentina. The grazing area contained abundant specimens of A. punae. The clinical course was ~15 d, and included moderate ataxia, incoordination of hindlimbs, and progressive loss of body condition. Microscopically, fine cytoplasmic microvacuolation was observed in the proximal convoluted renal tubules. Ultrastructurally, these changes consisted of severely dilated lysosomes. Swainsonine was detected in stem and leaf samples of A. punae at a concentration of 0.06%. Based on clinical history and signs, histologic and ultrastructural changes, and plant analysis, a diagnosis of swainsonine toxicosis caused by consumption of A. punae was made, which has not been reported previously, to our knowledge.

A New Species of Mimosa L. ser. Bipinnatae DC. (Leguminosae) from the Cerrado: Taxonomic and Phylogenetic Insights.

Mimosa carolina (Leguminosae), a new species from the Parque Nacional Chapada das Mesas, located in the northern limit of the Brazilian Cerrado, is described and illustrated. In addition, a phylogenetic reconstruction was performed to recover the position of this species in relation to the main clades of the genus Mimosa. This new species is assigned to sect. Habbasia ser. Bipinnatae and exhibits relevant morphological differences with all described species of this series, most notably the prostate habit, glabrous stems, and absence of internal spicules. Our results indicate that this new entity is clearly nested in a strongly supported clade with other striated-corolla species of ser. Bipinnatae. Therefore, ser. Bipinnatae appears to be monophyletic, and a morphologically and ecologically cohesive group within Mimosa. An updated identification key for this series is provided.

In Vitro Antifungal Activity of Peltophorum dubium (Spreng.) Taub. extracts against Aspergillus flavus.

Aspergillus flavus is a filamentous, saprophytic fungus, whose colonization occurs mainly in cereal grains and oilseeds once harvested. Under certain conditions, it could produce mycotoxins called aflatoxins, known as powerful human liver carcinogens. The aim of the present study was to describe the antifungal activity of extracts of Peltophorum dubium, a species from northern Argentina (Oriental Chaco), against A. flavus. The antifungal activities of different collection sites are reported. The extracts exhibited a minimum inhibitory concentration of 125 µg/mL, and the differences between the treatments and the inoculum control were 11 mm of P. dubium A and 10 mm of P. dubium F in colony growth. Moreover, hyphae treated with the extracts stained blue with Evans blue showed alterations in the membrane and/or cell wall, allowing the dye income. Bio-guided fractionation, High Performance Liquid Chromatography diode array ultraviolet/visible (HPLC UV/VIS DAD), and Ultra-High Performance Liquid Chromatography Electrospray Ionization Mass Spectrometry (UPLC ESI-MS) analyses were conducted to characterize the extracts and their active fractions. The HPLC UV/VIS DAD analysis allowed the determination of the presence of flavonoids (flavonols and flavones), coumarins, terpenes, and steroids. UPLC ESI/MS analysis of active fractions revealed the presence of Kaempferol, Apigenin, Naringenin, Chrysin and Daidzein.

Analysis of flavonoid glycosides with potential medicinal properties on Bauhinia uruguayensis and Bauhinia forficata subspecies pruinosa.

Several Bauhinia species are widely used in Southern South America in the treatment of infections, pain and several diseases including diabetes. Flavonoid compounds based on quercetin and kaempferol glycoside derivatives are believed to be responsible for their therapeutic properties. To investigate this, we have studied two native species from Argentina: B. uruguayensis (BU) and B. forficata subsp. pruinosa (BF). We have analyzed the major polyphenol components in hydro-methanolic extracts of leaves, by high performance liquid chromatography tandem mass spectrometry. Chromatographic analysis yielded five main compounds in BF, corresponding to rutinosides and rhamnosides derivatives of kaempferol and quercetin, which are considered chemotaxonomic markers and responsible for antioxidant activity. The presence of kaempferitrin, an antidiabetic agent, has been confirmed. In extracts of BU, four major compounds were identified as rhamnosides and galloyl derivates from quercetin and kaempferol. One of these compounds, quercitrin-3-rhamnoside may confer anti-inflammatory and analgesic properties to BU extracts.

Diversity and conservation of legumes in the Gran Chaco and biogeograpical inferences.

The Gran Chaco is a wide ecologic-geographic region comprising northern Argentina, western Paraguay, southern Bolivia and the southwestern extreme of Brazil. This region exhibits extreme temperatures, annually regular frosts, and sedimentary soils; it has been dramatically threatened by agriculture expansion in recent decades. Therefore, increasing knowledge of plant diversity is critical for conservation purposes. We present a Legume checklist of the Gran Chaco ecoregion including conservation status of its endemic species. Leguminosae is the third most diverse plant family in the Neotropics. Assuming a rigorous spatial definition of the Gran Chaco, we recorded 98 genera, 362 species, and 404 specific and infraspecific taxa. Endemic/typical taxa were 17%, comparable to adjacent tropical plant formations, and they were found in higher percentages in Caesalpinioideae (24%) and Cercidoideae (33%) than Papilionoideae (11%) subfamily. We also analyzed the plant diversity comparing lineages and subregions. The Gran Chaco Legumes are predominantly widespread generalists, or they belong to either Chaco sensu stricto or Neotropical Seasonally Dry Tropical Forest (SDTF) lineages. Though the Humid Chaco registered the highest species richness, Dry Chaco and Sierra Chaco, the most threatrened subregions, exhibited the highest percentages of exclusive and proper Chaco-lineage species. These results suggest that diversification of Legumes has been most relevant in Dry Chaco and Sierra Chaco, probably by their more demanding and harsh environmental conditions limiting the dispersion of generalists or intrusive-invading species. This study is paramount to reach an improved delimitation of the Gran Chaco ecoregion in transitional areas with the SDTF and Cerrado formations. Conservation status is critical in genera of high economic interest, such as Arachis, Mimosa and Prosopis. At least one third of endemic taxa exhibit a critical status of conservation or are endangered, many of them being relevant to inbreeding program or exhibiting multiple economic uses.

Genetic diversity and differentiation among Prosopis alba (Leguminosae) populations from dry valleys of Bolivia with different levels of human disturbance and altitude.

The fast expansion of human population around La Paz, Bolivia (3,200-4,100 m.a.s.l.) triggered new suburban settlements in nearby areas in valleys and mountain feet. The white mesquite, Prosopis alba Griseb. (Leguminosae), is a resource (originally used by native communities) that is strongly affected by changes in land use. A gradient in the level of disturbance is found moving away from the La Paz city toward less altitude areas. The main objective of this study was to characterize genetically three P. alba populations with different levels of human disturbance located at different altitudes in Bolivia, in order to provide some guidelines for management and conservation of these species. Based on 10 SSR loci, the populations showed high level of genetic diversity in comparison with other forest species. The population less disturbed and situated at the lowest altitude was the most variable (H e  = 0.51-0.42), whereas the less variable was the most disturbed and situated at the highest altitude. Heterozygote excess was observed in all populations. Most of genetic diversity (99%) is contained within populations. Genetic differentiation among populations is low (1%), suggesting low gene flow among populations. No evidence of recent bottlenecks events was detected. The estimates of the effective population size were low in all populations. The results are in agreement with the hypothesis that genetic diversity is reduced by the impact of anthropic disturbance in the population located at higher altitude in comparison with the lightly disturbed situated at lower altitude and farther from urban settlements.

Estudio farmacobotánico de Ipomoea purpurea (L) Roth (Convolvulaceae) / Pharmacobotanical study of Ipomoea purpurea (L.) Roth (Convolvulaceae)

Ipomoea purpurea (L.) Roth (Convolvulaceae) es una especie que se desarrolla en las zonas tropicales de ambos hemisferios. Por el atractivo de sus flores pertenece al grupo conocido como "Common morning glory", especies empleadas por diversos grupos nativos en rituales mágico - religiosos y popularmente como alucinógeno, analgésico, antiinflamatorio y purgante, entre otros. Dada la gran similitud de I. purpurea con otras especies del mismo género (características ecológica, morfológicas y fitoquímicas), se plantean actualmente discusiones de identificación incluso a nivel taxonómico. El objetivo de este estudio es determinar las principales características diagnósticas para la identificación de I. purpurea y registrar sus atributos morfoanatómicos generales. Se trabajó con material fresco proveniente de INTA Castelar y ejemplares de herbario. Se analizaron las hojas, tallos, raíces, flores y semillas. Se realizaron disociados leves, fuertes, raspados, reducción a polvo, cortes transversales, improntas de epidermis y peeling. Se realizaron reacciones histoquímicas para almidón, lípidos y antocianos. El material se observó mediante microscopía de luz clara, contraste de fase (DIC) y luz polarizada y se realizó microscopía cuantitativa. Entre los caracteres principales pueden mencionarse: en las hojas, epidermis con estomas paracíticos y anomocíticos, tricomas tectores unicelulares de tres tamaños diferentes, tricomas glandulares pluricelulares, drusas. En los tallos se observaron los mismos tricomas que en las hojas y tubos laticíferos. En la raíz, laticíferos, almidón y drusas. En la flor, tricomas tectores similares a los de las hojas pero con base ensanchada y tricomas glandulares, drusas, antocianinas y granos de polen equinados-pantoporados. En las semillas, esclereidas, lípidos, granos de almidón de diferente tamaño y de formas esférica y ovoidal, ambos con hendidura presente, drusas y cavidades, aparentemente, de tipo esquizógeno. Los tres tamaños diferentes de tricomas tectores, los tricomas glandulares y las cavidades presentes en la semilla constituyen la primera observación para esta especie. Este estudio proporciona datos relevantes para I. purpurea y provee elementos de diagnóstico para ser empleados en la diferenciación respecto de otras especies taxonómicamente afines. (AU)

Leaf venation pattern to recognize austral South American medicinal species of "cow's hoof" (Bauhinia L., Fabaceae)

ABSTRACT The leaves extracts of some species of Bauhinia L. s.l. are consumed to treat diabetes, inflammation, pains and several disorders in traditional medicine in austral South America. Despite its wide use and commercialization, sale is not controlled, and botanical quality of samples is not always adequate because of plant misidentification and adulteration. Here, we characterized leaf vein pattern in nineteen taxa to contribute to the recognition and commercial quality control of plant material commercially available. The vein characters intercostal tertiary and quinternary vein fabric, areole development and shape, free ending veinlet branching and marginal ultimate venation allowed to distinguish the main medicinal species in the region.

Sale of medicinal herbs in pharmacies and herbal stores in Hurlingham district, Buenos Aires, Argentina

In this paper, the sale of medicinal plants was described in the urban city of Buenos Aires, Argentina. Semi-structured interviews were conducted with pharmacists and herb store owners about different characteristics of retail. Likewise, different types of retailers were compared, and the phytomedicine degree of acceptance was consulted. The percentage of customers who buy medicinal plants in herb stores is higher than in pharmacies. The five most demanded species were: "malva" (Malva sp.), 18%; "manzanilla" (Matricaria recutita), 13%; "tilo" (Tilia sp.), 12%; "cuasia" (Picrasma crenata), 8%; and "boldo" (Peumus boldus), 7%. In like manner, the most demanded mixes of species were those that had slimming properties, 21%; digestive, 17%; sedative and diuretic, 13%. Of the 32 most frequently requested species, only 13 are native. Phytomedicines were widely accepted in the different kinds of retail stores. It was also emphasized that, contrary to the usual assumption, the choice to consume plants is cultural rather than economic. Due to the acceptance observed in the use of phytomedicines, it must be emphasized the potential that Argentina possesses for the development of this industry.