Abstract Detail

Anatomy and Morphology

Ely, Francisca [1], Fernández, José David [1], Kiyota, Sayuri [3], Clark, Lynn [4].

Comparative leaf anatomy of 10 Venezuelan Andean species of Chusquea Kunth (Poaceae: Bambusoideae).

With approximately 175 described species, Chusquea is the most diverse genus among the American woody bamboos, with representatives in Central and South America, distributed from Mexico to Argentina and Chile. The tropical Andes are a hotspot of the genus, where a great diversity of species occur between 2,500-3,000 m asl, associated to cloud forests and high altitude tropical grasslands known as páramos. The aim of this study was to compare the leaf anatomy of Venezuelan Andean species of Chusquea associated to these ecosystems along a broad altitudinal gradient, from 1,750 to 4,000 m asl, in order to include as many cloud forest and paramo bamboo species as possible. A total of 10 species were studied: 7 scandent cloud forest bamboos, Chusquea aurea, C. fendleri, C. maculata, C. multiramea, C. purdieana, C. serrulata and C. uniflora and 3 shrub-like paramo ones, C. angustifolia, C. guirigayensis and C. spencei. Plant material used for this study consisted of fresh leaves, collected in the field and fixed in FAA. Fixed leaves were then used for free hand, cross sections of the median portion of the leaf blade and epidermal peels. All of the preparations were stained with alcian-blue-safranine 0.5% (7:3), mounted in aqueous glycerin (50% glycerin, 50% water) and examined with light microscopy. All of the species were hypostomatic with exception of C. fendleri which was amphistomatic, and they shared anatomical characteristics typical of Chusquea: a mesophyll of 3-4 layers of arm cells, with deep invaginations in the inner walls, and papillae on the subsidiary cells of the stomatal complex. Epidermal characters such as prickles, long and short hairs and silica bodies varied greatly among species. However, these variations did not appear to be related to life-form, habitat, or the altitude at which these species grew. In contrast, other anatomical characters such as the dimensions of the bulliform cells, cuticle thickness, length of the abaxial epidermal papillae, number and arrangement of the midvein vascular bundles, as well as the development and dimensions of the mesophyll fusoid cells did vary consistently between cloud forest and paramo bamboos, and became more accentuated along the gradient. We hypothesize that these differences could be related to variations in the air temperature and the quality of the incident radiation along the cloud forest - paramo gradient sampled.

1 - Universidad de Los Andes, Avenida Alberto Carnevali, Núcleo Pedro Rincón Gutiérrez La Hechicera, Facultad de Ciencias 3cer piso Laboratorio de Anat, Mérida, Mérida, 5101, Venezuela
2 - Universidad de Los Andes, Avenida Alberto Carnevali, Núcleo Pedro Rincón Gutiérrez La Hechicera, Facultad de Ciencias 3cer piso Laboratorio de Anat, Mérida, Mérida, 5101, Venezuela
3 - Université de Sciences Montpellier , Herbarium, Montpellier, France
4 - Iowa State University, Department Of Ecology, Evolution, And Organismal Biology, 251 Bessey Hall, Ames, IA, 50011-1020, USA

Keywords:
Altitude Gradient
Cloud Forests
Paramos
Woody Bamboos.

Presentation Type: Oral Paper
Session: 20, Anatomy and Morphology
Location: Fort Worth Ballroom 7/Omni Hotel
Date: Tuesday, June 27th, 2017
Time: 9:30 AM
Number: 20007
Abstract ID:338
Candidate for Awards:None