Homobaric and heterobaric leaves in different cerrado physiognomies and relations between leaf anatomy and gas exchanges

• Grant number: 14/12482-2
• Support Opportunities: Regular Research Grants
• Start date: October 01, 2014
• End date: March 31, 2017
• Field of knowledge: Biological Sciences - Botany - Plant Morphology
• Principal Investigator: Tatiane Maria Rodrigues
• Grantee: Tatiane Maria Rodrigues
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated researchers: Amanda Cristina Esteves Amaro ; Carmen Sílvia Fernandes Boaro ; Silvia Rodrigues Machado

Abstract

Bundle-sheath extensions (BSE) in heterobaric leaves display important roles in water conduction, responses to water stress and light transmission to inner layers of the mesophyll, improving the photosynthetic performance. On the other hand, homobaric leaves, lacking BSE, provide greater lateral movement of gases. Plant species bearing heterobaric leaves occur preferentially in deciduous forests while homobaric leaves are dominant in evergreen forests. In addition, most of the species from the understory in tropical forests present homobaric leaves, whereas the emergent species or plants growing in forest gaps have heterobaric leaves. Our aim is to investigate the distribution of plant species with homobaric and heterobaric leaves in cerradão and cerrado stricto sensu in order to associate the presence/absence of BSE to the plant habit, physiological indexes, stomata density and environmental light condictons. In each area, a 20mX20m square will be delimited. Samples of expanded leaves will be prepared for studies under light and scanning electron microscopes. The leaf area and dry mass will be measured in order to obtain the specific leaf weight. The gas exchange indexes and light conditions of the environment will be measured by IRGA (Infra Red Gas Analyser). The distribution of homobaric and heterobaric leaves among herbs, shrubs and trees and between cerradão and stricto sensu cerrado will be evaluated by Chi-square test. The physiological and ultrastructural features of the different leaf types will be submitted to variance analysis and Tukey test (5% significance); for the comparison between Cerrado physiognomies will be employed a combined analysis. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RODRIGUES, TATIANE MARIA; ESTEVES AMARO, AMANDA CRISTINA; FERNANDES BOARO, CARMEN SILVIA; MENDES, KATIANE REIS; DE MELO SILVA, STEFANY CRISTINA; FERREIRA JUNIOR, VALDEMIR; MACHADO, SILVIA RODRIGUES. Four distinct leaf types in the Brazilian Cerrado, based on bundle sheath extension morphology. BOTANY, v. 95, n. 12, p. 1171-1178, DEC 2017. (14/12482-2)

MENDES, KATIANE REIS; MACHADO, SILVIA RODRIGUES; ESTEVES AMARO, AMANDA CRISTINA; MELO SILVA, STEFANY CRISTINA; FERREIRA JUNIOR, VALDEMIR; RODRIGUES, TATIANE MARIA. Distribution of homobaric and heterobaric leafed species in the Brazilian Cerrado and seasonal semideciduous forests. FLORA, v. 225, p. 52-59, NOV 2016. (14/12482-2)