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Phytotelma refers to the water accumulated in certain plant structures that constitute the main natural microhabitats for the development of mosquitoes. This study aimed to identify native and exotic plants with phytotelmata and their mosquito fauna (Diptera, Culicidae) in a subtropical area of northeastern Argentina, looking for new records of plant-mosquito associations. The samples were collected bimonthly during 2015-2017 at two sites in each of three localities in the Formosa, Corrientes and Chaco provinces. Species of Apiaceae, Araceae, Arecaceae, Bromeliaceae, Fabaceae, Poaceae and Strelitiaceae were identified as having phytotelmata and all except the latter harbored mosquitoes. Most woody phytotelmata were found in native bamboo Guadua chacoensis (Poaceae), which harbored six culicid species mainly of the Sabethini tribe. The herbaceous phytotelmata with the highest abundance were found in native Aechmea distichantha (Bromeliaceae), which harbored four culicid species, most of the Culicini tribe. New records of culicids that inhabit native phytotelmata in Argentina include Haemagogus spegazzinii in Prosopis nigra and Culex coronator in Acrocomia aculeata, and in exotic phytotelmata include Wyeomyia codiocampa and Toxorhynchites theobaldi in Bambusa vulgaris. Furthermore, two species of the Microculex subgenus were found in Alocasia macrorrhiza and one in Aechmea miniata. The diversity of native plant species with phytotelmata is an important factor in supporting a diverse assemblage of Culicidae, playing a relevant role in the conservation of mosquito diversity. [ABSTRACT FROM AUTHOR]

BACKGROUND The present study combines morphological and anatomical studies, cell wall chemical composition analysis, as well as assessment of the nutritional value of Guadua chacoensis foliage leaves. RESULTS Foliage leaves of G. chacoensis are a promising source of forage because: (a) as a native woody bamboo, it is adapted to and helps maintain environmental conditions in America; (b) leaf anatomical studies exhibit discontinuous sclerenchyma, scarcely developed, while pilose indumentum, silica cells, prickles and hooks are also scarce; (c) it has a high protein content, similar to that of Medicago sativa, while other nutritional parameters are similar to those of common forages; and (d) glucuronoarabinoxylan, the major extracted polysaccharide, has one-third of the 4-linked β- d-xylopyranosyl units of the backbone substituted mainly with α- l-arabinofuranose as single stubs or non-reducing end of short chains, but also 5-linked α- l-arabinofuranose units, terminal β- d-xylopyranose and d-galactopyranose units, as well as α- d-glucuronic acid residues and small amounts of its 4- O-methylated derivative. CONCLUSION These results constitute the first report on this species, and as culms are utilized in constructions and crafts, the remaining leaves, when used as forage, constitute a byproduct that allows an additional income opportunity. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Fusoid cells have been interpreted as cells or intercellular spaces, according to different authors. Here, structural and ultrastructural evidence is provided relative to the origin and changes experimented by chlorenchyma cells (“arm cells”) to differentiate into fusoid cells with large intercellular spaces between them. Performed studies and observations were made using Light and Transmission Electron Microscopy. Fusoid cells in Guadua species die but do not remain intact; instead, they uniformly collapse, delimiting conspicuous intercellular spaces which are bigger and different in shape from these cells. In transverse sections of mature and expanded bamboo leaf blades, usually seen in anatomical descriptions, the so-called “fusoid cells” are actually conspicuous intercellular gas spaces delimited by successive collapsed (and rarely not collapsed) fusoid cells. Also, we hypothesize possible relations or links between fusoid cell shape, structural function and apoplastic transport in bamboo leaves. [ABSTRACT FROM AUTHOR]

Andrada, Aldo R.; Lozzia, María E. & Cristóbal, María E. 2007. “Contribución al conocimiento de Guadua chacoensis”. Lilloa 44 (1-2). Se llevan a cabo estudios citológicos en Guadua chacoensis (Rojas) Londoño & Peterson, en flores y frutos coleccionados en el ciclo que se inició en noviembre del 2006; el ciclo floral anterior fue hace 30 años. Se estudia la meiosis, y se determinaron los porcentajes de viabilidad y germinabilidad del polen y los de germinación de semillas. Se contaron 2n=46 cromosomas mitóticos y en la meiosis se observaron irregularidades.

Parrado, María Francisca y Nora De Marco, 2006. ?Floración de Guadua chacoensis (Poaceae: Bambuseae)?. Lilloa 43 (1-2). El objetivo de la presente comunicación es dar a conocer la floración de Guadua chacoensis (Rojas) Londoño y P. M. Peterson, en la provincia de Tucumán. En el Jardín Botánico de la Fundación Miguel Lillo crecen matas de esta especie que proceden de Iguazú, Misiones. Las mismas iniciaron su floración-fructificación en el mes de agosto de 2006, los registros anteriores son del año 1976. Estos datos nos permiten aproximar ciclos de floración de 30 años.

• Major amounts of glucuronoarabinoxylans (GAX) were obtained from bamboo shoots. • Exhaustive alkaline extraction and alternative extraction with DMSO were performed. • GAX showed acetylation mainly on C3, but also on C2 of some xylose units. • Arabinogalactans and pectins, mixed linkage glucans and xyloglucans were obtained. • The whole cell wall polysaccharide system from this raw material was characterized. Guadua is a genus of woody bamboos, native to the American continent, which comprises economically important species. Cell wall polysaccharides from young shoots of Guadua chacoensis showed glucuronoarabinoxylans (GAX) as the major hemicellulosic components (65%, of the recovered carbohydrates by extraction with aqueous solutions), which were obtained in major quantities with 1 M KOH (molar ratio Xyl:Ara:GlcA, 100:28:8). AGP and pectin polymers, as well as mixed linkage glucans and xyloglucans were present in smaller amounts (16% and 15%, respectively). Alternative extraction of GAX with solutions of DMSO allowed the characterization of alkali labile substituents, in particular, acetyl groups, which were linked mainly to C3 or, to a lesser extent, to C2 of some of the xylose residues. Besides, small amounts of phenolic compounds, released by saponification, were detected, linked to C5 of some α- l -arabinofuranose units. These results could be relevant for their use as a new resource for the food industry. [ABSTRACT FROM AUTHOR]