Advanced search
Start date
Betweenand
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Seasonality and growth rings in lianas of Bignoniaceae

Full text
Author(s):
Lima, Andre C. [1] ; Pace, Marcelo R. [1] ; Angyalossy, Veronica [1]
Total Authors: 3
Affiliation:
[1] Univ Sao Paulo, Inst Biociencias, Dept Bot, BR-05588090 Sao Paulo - Brazil
Total Affiliations: 1
Document type: Journal article
Source: TREES-STRUCTURE AND FUNCTION; v. 24, n. 6, p. 1045-1060, DEC 2010.
Web of Science Citations: 18
Abstract

Lianas are one of the most important components of tropical forest, and yet one of the most poorly known organisms. Therefore, our paper addresses questions on the environmental and developmental aspects that influence the growth of lianas of Bignoniaceae, tribe Bignonieae. In order to better understand their growth, we studied the stem anatomy, seasonality of formation and differentiation of secondary tissues, and the influence of the cambial variant in xylem development on a selected species: Tynanthus cognatus. Afterwards, we compared the results found in T. cognatus with 31 other species of Bignonieae to identify general patterns of growth in lianas of this tribe. We found that cambial activity starts toward the end of the rainy season and onset of the dry season, in contrast to what is known for tropical trees and shrubs. Moreover, their pattern of xylem formation and differentiation is strongly influenced by the presence of massive wedges of phloem produced by a variant cambium. Thus, the variant cambium is the first to commence its activity and only subsequently does cambial activity progress towards the center of the regular region, leading to the formation of confluent growth rings. In summary, we conclude that: the cambium responds to environmental changes; the xylem growth rings are annual and produced in a brief period of about 2 months, something that may explain why lianas possess narrow stems; and furthermore, phloem wedges greatly influence cambial activity. (AU)