Affiliation:
1. Instituto de Pesquisa Jardim Botânico do Rio de Janeiro, DIPEQ, R. Pacheco Leão 915, Rio de Janeiro, RJ 22460-030, Brazil.
2. Embrapa Clima Temperado, BR 392 km 78, Pelotas, RS 96010-971, Brazil.
Abstract
Baccharis L. is an important genus in the high-altitude environments of South America. In the State of Rio de Janeiro, southeastern Brazil, the greatest richness is found at montane and high-montane ecological refuges, known as high-altitude grasslands. The high altitude provides several environmental factors that turn the high-altitude grasslands into singular tropical habitats. In this article we describe the leaf anatomy of six shrubby species of Baccharis, pointing out ecological aspects of the structures, and testing the use of statistical analyses to compare the species. Using light and scanning electron microscopy, we compared the anatomical features of the leaves and performed a cluster and principal component analyses. The results show novel features in the leaf anatomy for the genus, such as an undulated cuticle, three secretory ducts in the midrib, secretory ducts associated with the xylem, and biseriate glandular trichomes with an irregular organization of the cells. Our statistical analyses indicate that the anatomical features of the leaves, especially trichomes, are useful for distinguishing the different species, whereas others, such as isobilateral mesophyll, amphistomatic leaves, and an epidermis with thick cell walls correlate with their high-elevation habitat.
Publisher
Canadian Science Publishing
Subject
Plant Science,Ecology,Ecology, Evolution, Behavior and Systematics
Cited by
3 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献