The utility of Bambusoideae (Poaceae, Poales) leaf blade anatomy for identification and systematics / A utilidade da anatomia da lâmina foliar para a identificação e sistemática de espécies de Bambuboideae (Poaceae, Poales)

Abstract Bambusoideae is a diverse subfamily that includes herbaceous (Olyreae) and woody (Arundinarieae and Bambuseae) bamboos. Species within Bambusae are particularly difficult to identify due to their monocarpic lifecycle and the often long durations between mass flowering events; whereas the herbaceous bamboos are pluricarpic, but often are found with no reproductive structures. The leaf blade anatomy of 16 sympatric species of native Brazilian bamboos (Olyreae and Bambuseae) from the Atlantic Rainforest was studied in order to detect useful features for their identification. All the studied species share the following features: epidermis with a single stratum of cells; adaxial bulliform cells; mesophyll with arm cells, rosette cells, and fusoid cells; and collateral vascular bundles. Herbaceous bamboos share two features: papillae scattered on the abaxial surface and parallel-sided arrays of bulliform cells; whereas woody bamboos share: centrally organized papillae and fan-shaped arrays of bulliform cells. Also within the woody bamboos, intercostal fibers and a midrib with only one vascular bundle (simple midrib) characterize the subtribe Arthrostylidiinae; whereas a midrib with more than one vascular bundle (complex midrib) and a stomatal apparatus with two pappilae per subsidiary cell characterize the subtribe Chusqueinae. There are also diagnostic features for the sampled species, such as: papillae shape, and the outline and structure of the midrib. An identification key for all the studied species is provided based on the anatomical features.

Resumo Bambusoideae é uma subfamília que inclui diversas espécies de bambus herbáceos (Olyreae) e lignificados (Arundinarie e Bambuseae). Bambus lignificados geralmente apresentam dificuldades de delimitação e identificação, devido principalmente ao ciclo monocárpico e longa amplitude temporal entre florações; enquanto que bambus herbáceos possuem ciclo pluricárpico, porém frequentemente são encontrados em estágio vegetativo. Foi estudada a anatomia da lâmina foliar de 16 espécies de Bambusoideae (Olyreae e Bambuseae), simpátricas e nativas do Brasil, visando levantar caracteres úteis para sua identificação. Todos os táxons estudados compartilham: epiderme uniestratificada; células buliformes na face adaxial; mesofilo com células invaginantes, células em roseta e células fusoides; e feixes vasculares colaterais. Bambus herbáceos compartilham: papilas dispersas na face abaxial e grupos de células buliformes organizadas paralelamente; enquanto que bambos lignificados compartilham: papilas organizadas em colunas centrais e grupos de células buliformes em forma de leque. Ainda dentre os bambus lignificados, fibras intercostais e nervura central com apenas um feixe vascular (nervura central simples) caracterizam a subtribo Arthrostylidiinae; enquanto que nervura central com mais de um feixe vascular (nervura central complexa) e aparelho estomático com duas papilas por célula subsidiária caracterizam a subtribo Chusqueinae. Há ainda caracteres anatômicos diagnósticos, tais como: forma da papila, e forma e estrutura da nervura central. Uma chave de identificação é fornecida baseada nos caracteres anatômicos relevantes à identificação das espécies estudadas.

The utility of Bambusoideae (Poaceae, Poales) leaf blade anatomy for identification and systematics.

Bambusoideae is a diverse subfamily that includes herbaceous (Olyreae) and woody (Arundinarieae and Bambuseae) bamboos. Species within Bambusae are particularly difficult to identify due to their monocarpic lifecycle and the often long durations between mass flowering events; whereas the herbaceous bamboos are pluricarpic, but often are found with no reproductive structures. The leaf blade anatomy of 16 sympatric species of native Brazilian bamboos (Olyreae and Bambuseae) from the Atlantic Rainforest was studied in order to detect useful features for their identification. All the studied species share the following features: epidermis with a single stratum of cells; adaxial bulliform cells; mesophyll with arm cells, rosette cells, and fusoid cells; and collateral vascular bundles. Herbaceous bamboos share two features: papillae scattered on the abaxial surface and parallel-sided arrays of bulliform cells; whereas woody bamboos share: centrally organized papillae and fan-shaped arrays of bulliform cells. Also within the woody bamboos, intercostal fibers and a midrib with only one vascular bundle (simple midrib) characterize the subtribe Arthrostylidiinae; whereas a midrib with more than one vascular bundle (complex midrib) and a stomatal apparatus with two pappilae per subsidiary cell characterize the subtribe Chusqueinae. There are also diagnostic features for the sampled species, such as: papillae shape, and the outline and structure of the midrib. An identification key for all the studied species is provided based on the anatomical features.

Anther and pollen development in some species of Poaceae (Poales).

Anther and pollen development were studied in Olyra humilis Nees, Sucrea monophylla Soderstr, (Bambusoideae), Axonopus aureus P. Beauv., Paspalum polyphyllum Nees ex Trin. (Panicoideae), Eragrostis solida Nees, and Chloris elata Desv. (Chloridoideae). The objective of this study was to characterise, embryologically, these species of subfamilies which are considered basal, intermediate and derivate, respectively. The species are similar to each other and to other Poaceae. They present the following characters: tetrasporangiate anthers; monocotyledonous-type anther wall development, endothecium showing annular thickenings, secretory tapetum; successive microsporogenesis; isobilateral tetrads; spheroidal, tricellular, monoporate pollen grains with annulus and operculum. Nevertheless, the exine patterns of the species studied are distinct. Olyra humilis and Sucrea monophylla (Bambusoideae) show a granulose pattern, whereas in the other species, it is insular. In addition, Axonopus aureus and Paspalum polyphyllum (Panicoideae) have a compactly insular spinule pattern, while Chloris elata and Eragrostis solida (Chloridoideae) show a sparsely insular spinule pattern. The exine ornamentation may be considered an important feature at the infrafamiliar level.

Developmental anatomy and morphology of the ovule and seed of heliconia (heliconiaceae, zingiberales).

The developmental anatomy and morphology of the ovule and seed in several species of Heliconia were investigated as part of an embryological study of the Heliconiaceae and to provide a better understanding of their relationships with the other families of the Zingiberales. Heliconia species have an ovule primordium with an outer integument of both dermal and subdermal origin. The archesporial cell is divided into a megasporocyte and a single parietal cell, which in turn are divided only anticlinally to form a single parietal layer, disintegrating later during gametogenesis. The embryo sac was fully developed prior to anthesis. In the developing seed, the endosperm was nuclear, with wall formation in the globular stage; a nucellar pad was observed during embryo development, but later became compressed. The ripe fruit contained seeds enveloped by a lignified endocarp that formed the pyrenes, with each pyrene having an operculum at the basal end; the embryo was considered to be differentiated. Most of these characteristics are shared with other Zingiberales, although the derivation of the operculum from the funicle and the formation of the main mechanical layer by the endocarp are unique to the Heliconiaceae.