Maria Manuela Chaves Lab
Our general interests concern the understanding of physiological and molecular mechanisms underlying plant responses to environmental stresses as well as the differences among genotypes in the capacity to utilize external resources.
Maria Manuela Chaves
Phone (+351) 214469641
Growth and development of plants is largely dependent on external conditions. Usually, plants grow slower than their theoretical optimal rate because one or more essential factors are limiting, e.g., light, temperature, available water, etc.
This research group studies the interaction between plants and the environment. The analysis of plant responses to stressful conditions from the molecular up to the level of the intact plant allows a fully integrated understanding of plant-environment interaction. LEM has expertise in the study of the mechanisms which contribute to determine photosynthesis, transpiration, plant growth, yield and fruit quality of plants subjected to various abiotic stresses. More efficient and sustainable utilization of resources such as water by plants becomes a high research priority to cope with the consequences of exploding demographic trends and challenging climate changes. This requires renewed knowledge on plant adaptability to marginal lands and sub-optimal environments. At present, most of our studies are concentrated on grapevines.
We have shown in grapevine that large fluxes of water are not essential for optimal crop performance. Moderate water deficits, induced by irrigation below evapotranspiration (deficit irrigation), influence berry ripening and quality, through the stimulation of sugar and anthocyanin biosynthesis under a mild to moderate water deficits. Our results showed that season temperature has a key role on the success of the deficit irrigation. Deficit irrigation has a positive effect on berry quality only when the high temperature is not a limiting factor.
The analysis of water/heat stresses on grape berry cuticle (e.g. anatomy, composition, permeability) is a matter of research. Taking advantage of the available genetic resources of Vitis genome our investigations on cuticle aim at determining how water deficit and heat stress affect berry cuticle physiology, morphology and biochemistry during berry development and the transcriptional and protein networks underlying these changes.
- Olfa Zarrouk, Post-Doctoral fellow
Carla Pinheiro, PhD Visiting Scientist from FCT, UNOVA
Ana Fortunato, PhD with a research fellowship
ZARROUK O, BRUNETTI C, EGIPTO R, PINHEIRO C, GENEBRA T, GORI A, LOPES CM, TATTINI M AND CHAVES MM 2016 Grape ripening is regulated by deficit irrigation/elevated temperatures according to cluster position in the canopy. Frontiers in Plant Science 7:1640. doi: 10.3389/fpls.2016.01640
CHAVES MM, COSTA JM, ZARROUK O, PINHEIRO C, LOPES CM, PEREIRA JS 2016 Controlling stomatal aperture in semi-arid regions − the dilemma of saving water or being cool? Plant Science 251, 54-64. doi:10.1016/j.plantsci.2016.06.015.
COSTA JM, VAZ M, ESCALONA J, EGIPTO R, LOPES C, MEDRANO H, CHAVES MM 2016 Modern viticulture in southern Europe: Vulnerabilities and strategies for adaptation to water scarcity. Agricultural and water management 164, 5–18 DOI: 10.1016/j.agwat.2015.08.02
For further information please visit the laboratory's website
O Laboratório de Ecofisiologia Molecular de Plantas dedica-se ao estudo da tolerância das plantas ao stresse abiótico, em particular à identificação dos mecanismos de regulação (desde o nível molecular ao nível ecofisiológico) que permitem a adaptação das plantas às alterações do ambiente. Outro dos nossos objetivos é a caracterização fisiológica de genótipos no que respeita a sua eficiência de utilização de recursos do meio (ex. água e azoto), com impacto nas técnicas culturais e no melhoramento vegetal. A videira (Vitis vinífera L.) pela importância na produção vitivinícola nacional tem sido o nosso principal objeto de estudo.