Contributos para o melhoramento em sobreiro: instalação de rebentos in vitro visando a obtenção de híbridos. Fenologia da espécie e ontogenia da sua reprodução sexuada

Mestrado em Engenharia Agronómica - Horticultura e Viticultura - Instituto Superior de AgronomiaFocusing cork-oak breeding, we assayed in vitro establishments of apical and nodal segments from mature trees of Quercus suber L. collected directly from the field, in order to reach a prompt method for controlled pollinations of female flowers established in vitro. The plant material used for in vitro establishment was sampled between April and September 2013 from a plot in south of Setúbal peninsula. In this context, phenology was monitored in a population of 31 trees from the same plot and the ontogenic development of reproductive female structures and acorns of one tree was histologically studied. The in vitro development of explants was very difficult, due to contaminations, tissue oxidation and low reactivity of explants, looking more promising the use of shoots in mouse-ear phenological stage (at the beginning of axis elongation) collected in spring, superficial sterilizations with solutions of calcium hypochlorite and fungicides and culture in agar water, with foliar fertilizer applications, prior being transferred to nutritive medium. Phenological data showed intraspecific variation and sporadic flowering, outside spring. Relationships between phenology and ontogeny were recognized, and a long progamic phase (80 days) and an early full differentiation of embryos have been documente

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved