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| Author(s): |
Fernanda Anselmo Moreira
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) |
| Defense date: | 2015-11-06 |
| Examining board members: |
Cláudia Maria Furlan;
Paula Novaes;
Deborah Yara Alves Cursino dos Santos
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| Advisor: | Cláudia Maria Furlan |
| Abstract | |
Parasitic plants are those that withdraw necessary resources for its survival from other plants (hosts) through a structure so-called haustorium which enables the parasite to connect to the host\'s vascular system. Plants can respond to the parasite attack activating some defense mechanisms, including the production of phenolic compounds. Mistletoes are a group of stem parasitic plants belonging to Santalales that can be grouped into holoparasite or hemiparasite mistletoes. Some mistletoes genera are of economic importance among them Phoradendron, a hemiparasite mistletoe. This study aimed to determine the contents of tannins, flavonoids, phenylpropanoids, soluble carbohydrates, starch, lipids, the carbon⁄nitrogen ratio and evaluate how the parasitic relationship affects the metabolism of the involved species. Were collected in Camapanha (MG) leaves and branches from six non−parasitized individuals of Tapirira guianensis, host plant (LT and BT). From nine parasitized individuals of T. guianensis were collected branches and leaves of Phoradendon crassifolium, the parasitic plant (LP and BP), non-infested host branches and their leaves (NIHB and NIHB-L) and infested branches and their leaves (IHB and IHB-L). Infested branches of T. guianensis were divided into proximal, gall, and distal regions (IHB-P, IHB-G and IHB-D). Main results were an increase in the proanthocyanidin and soluble carbohydrates content in NIHB−L and IHB−L in relation to LT. There was a reduction of soluble carbohydrate, starch, lipids, nitrogen, and phenolic compounds in infested branches, except in the gall region (IHB-G), which showed an increase of flavonoids and starch contents. It was also observed that NIHB appears to accumulate phenolic compounds. Results showed that P. crassifolium affects the primary and secondary metabolism of T. guianensis, and branches were affected more intense than the leaves. It can be suggested that the parasite withdraws nitrogen and soluble carbohydrates from its host and this could result in possible carbon relocation for growth, development, maintenance, and also defense of branches not yet infested. In addition, it could be suggested the accumulation of phenolic compounds in non−infested branches (NIHB) as a defense mechanism used by the host in order to prevent or even reduce new infestations of an individual already parasitized. (AU) | |
| FAPESP's process: | 13/23322-3 - Phenolic compounds, carbohidrates and lipids in the parasitic interaction of Tapirira guianensis (Anacardiaceae)and Phoradendron crassifolium (Santalaceae) |
| Grantee: | Fernanda Anselmo Moreira |
| Support Opportunities: | Scholarships in Brazil - Master |