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| Author(s): |
Lucas Cutri
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2013-02-18 |
| Examining board members: |
Marcelo Carnier Dornelas;
Marcos José Salvador;
Claudia Regina Baptista Haddad;
Maria Helena de Souza Goldman;
Marcio Alves Ferreira
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| Advisor: | Marcelo Carnier Dornelas |
| Abstract | |
The genus Passiflora comprises more than 600 species of lianas and small shrubs. The typical flowers of Passiflora congregate a series of morphological and physiologic innovations that allow adaptation to a number of pollinating agents. The volatile compounds present in the flower scent ("headspace") are important features to the effective reproduction of plant species since they act in the attraction of the correct pollinating agent. These compounds emitted by flowers are basically of low-molecular weight, mostly lipophilic and are represented by very different chemical classes. The aim of this work was the analysis of the volatile compounds present in the floral "headspace" of three different Passiflora species pollinated by bees, hummingbirds and bats (Passiflora edulis, P. coccinea and P. mucronata, respectively). Solid phase micro extraction (SPME) coupled to GC-MS analysis was the analytical tool in that study. The results showed different patterns of volatile compounds in the floral "headspace" of P. edulis, P. coccinea and P. mucronata. The "headspace" of P. edulis contained phenylproanoids mostly represented by methylated benzenes, P. coccinea, terpenes and P. mucronata terpenes, alkanes, fatty acid derivative, and sulphur-containing compounds. Genes potentially involved with the synthesis of key enzymes of volatile compounds pathways were identified in an Expressed Sequence Tag (EST) database obtained from reproductive tissues of P. edulis (PASSIOMA). Among these PePAL and PeOMT possibly involved with the production of methylated benzenes that acting in the insect attraction in different plant species. PePAL and PeOMT had their expression patterns analyzed by quantitative and semi-quantitative RT-PCR as well as by in situ hybridization. This approach confirmed that the phenylpropanoid pathway is active in flowers of P. edulis, especially in the epithelial tissue in corona filaments that has ultra-structural features of secretor cells. This work emphasizes the chemical differences in scent flower among Passiflora species, and shows two genes potentially involved in scent flowers production in P. edulis (AU) | |