Annual Report 2011
Research Highlights
P Plant Molecular Ecophysiology Manuela Chaves
mchaves@itqb.unl.pt
Grapevine varieties exhibiting differences in stomatal response to water deficit. Vitis vinifera has large genetic variation and knowledge of genotype/variety traits and related physiological responses to abiotic stress is still scarce. This limits the optimization of irrigation and breeding strategies for higher water use efficiency. Thermal imaging is feasible technique to remotely measure plant’s temperature, and indirectly, assess plant’s transpiration and water status. The physiology behind this lies in the fact that when leaf stomata close, transpiration is reduced, leading to higher leaf temperatures as compared to leaves with open stomata. In field trials, we characterized five varieties by using thermal imaging and leaf gas-exchange: Aragonez, Trincadeira, Cabernet-Sauvignon, Syrah and Touriga Nacional. Leaf temperature (Tleaf) determined by thermal imaging correlated negatively with stomatal conductance to water vapour (gs) in both trials. The inverse relationship between gs and Tleaf was highly significant in the afternoon. When comparing the five genotypes, they showed different Tleaf for similar water status (Ψpd). Leaf stomatal density did not correlate with gs suggesting that varieties have different stomatal control. Our results also show that combined measurements of canopy temperature and Ψpd can lead to better understanding of stomatal regulation in different grapevine varieties. Such variation in stomatal regulation should be taken into account in determining irrigation strategies. Costa J.M. et al. (2012) Funct Plant Biol, 39(3)179
T Applied and Environmental Mycology Cristina Silva Pereira
spereira@itqb.unl.pt
Environmental pollution is a critical concern worldwide and fungal bioremediation constitutes an elegant and environment-friendly solution. In 2011, we conducted studies which unravelled the degradation pathway of pentachlorophenol by Mucor plumbeus. This fungus efficiently transforms the xenobiotic to less toxic compounds through a series of oxidative–reductive dechlorinations and taking advantage of phase II conjugation reactions to keep low toxic intracellular levels. For the first time, sulfate–glucose conjugates were identified in fungi. Mucor plumbeus might play an important role in the protection of less tolerant strains in pentachlorophenol contaminated environments. In the context of the remedial potential of filamentous fungi, we have identified several fungal strains from extreme soil biotypes, able to survive high concentrations of ionic liquids. This capacity might be related to the environmental pressure caused by high petroleum hydrocarbon load and, secondarily, by high salinity in soil. Our aspiration is to develop novel technologies, exploiting ionic liquids’ ability to augment fungal bioremediation. Ionic liquids’ rapid advance towards applications requires a comprehensive determination of their environmental, health and safety impact. Inspired by this, we have compiled an extensive and critical review focusing on ionic liquid environmental acceptability. Carvalho M.B. et al. (2011) J Haz Mat, 198, 133 Deive F.J. et al. (2011) Green Chem, 13(3) 687 Petkovic M. et al. 82011) Chem Soc Rev, 40(3)1383
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