Comparative morphology and evolution of the anther and the pollen grain of Cyperaceae

• Grant number: 14/05726-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: June 01, 2014
• End date: May 31, 2016
• Field of knowledge: Biological Sciences - Botany - Plant Morphology
• Principal Investigator: Simone de Pádua Teixeira
• Grantee: Juca Abramo Barrera San Martin
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Cyperaceae is considered the third largest family of monocotyledonous comprising 104 genera, with about 5,000 widely distributed species. Cyperaceae together with Thruniaceae and Juncaceae form the Cyperid clade. The family has important cytological features as holokinetic chromosomes and post-reductional meiosis. Furthermore, no tetrad is formed during the androsporogenesis; the four nuclei results of meiosis are contained in a single cell, called pseudomonad. Three of the four nuclei degenerate and only one becomes viable, forming the vegetative and generative cells. Phylogenetic relationships within the Cyperaceae are not completely understood. Moreover, morphological data are constantly confronted with molecular ones. Embryological characters are more conserved than vegetative characters, since they are much more affected by genetic programming rather than environmental conditions. Thus, the association of the molecular data with the embryological data would provide greater reliability in the interpretation of phylogenetic relationships in Cyperaceae. The aim of this project is to study the morphology of anther, androspore and androphyte within the Cyperid clade. The evolution of some chosen characters will also be addressed. For that, material of 30 species of the Cyperid clade will processed for observation under light microscopy, and scanning and transmission electron microscopy. The survey of these data will contribute to the understanding of floral adaptations in evolutionary and ecological contexts in the group. (AU)