Wood anatomy of Brazilian genera of Loranthaceae

Abstract

Parasitic plants represent around 1% of all the angiosperm diversity and are defined by the presence of a specialized organ called haustorium. This organ is responsible by the invasion of the host-plant body and the formation of a vascular bridge between the host's vascular system and the parasite's vascular system, allowing the exchange of substances between both of them. Normally, the interaction between host and parasite leads to a loss of vigor by the hosts and, in more extreme cases, their death. These effects on the host fitness may cause a series of ecological impacts on communities, that vary from negative effect such a reduction on the overall production at the community level , up to a positive effect like the maintenance of the diversity of the community. The morphological wood characteristics are closely related to functional aspects of a plant like the efficiency and security in water transport. The Loranthaceae is the third largest family in number of parasitic species among the land plants and is the family with the majority of parasitic genera in the Santalales order. Of the 77 genera within the family, 12 genera (containing around 133 species) occur in Brazil, in a diversity of habitats. Although the diversity is very important, but the number of studies about wood anatomy of the native species are still quite low, being very underrepresented in most of textbooks whenever it's present. The project presented here has as its main objective of expanding the knowledge on wood anatomy, that may provide subsidies for ecological anatomy, systematics and ecophysiology. This description would be done by the preparation of histological slides of the mature wood of the target species and macroscopic analysis and light microscopy techniques. For that, this study wants to analyse material from many differents xylaria or acquired by field trips, containing at least one species of each genus occuring in Brazilian territory.