Growth and morphophysiological responses of eucalyptus seedlings exposed to high [CO2] and elevated temperature

• Ano de defesa: 2018
• Autor(a) principal: Pinto, Samuel de Souza
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Viçosa
• Palavras-chave em Português: Eucalipto - Mudas - Crescimento; Troca gasosa em plantas; Eucalipto - Metabolismo; Mudanças climáticas; Ecofisiologia Vegetal
• Link de acesso: https://locus.ufv.br//handle/123456789/27561

The area planted with tree species is growing significantly in recent years and the main genus used is Eucalyptus. However, the adequate development of the crop is dependent on several factors such as concentration of carbon dioxide ([CO2 ]) and temperature. Climate changes, mostly related to increases in [CO 2 ] and atmospheric temperature are expected, which will most likely result in changes in plant growth and development. Although the effects of [CO2 ] have been extensively studied, and recent works indicated that high [CO2 ] might mitigate the impacts of high temperature, the interaction between these two environmental factors have not been addressed in eucalyptus to date. Thus, the objective of this work was to investigate responses in eucalyptus seedlings exposed to high [CO2] and elevated temperature using mini-FACE system. To this end, seedlings of two eucalyptus clones were cultivated for sixty-two days in environment with High [CO2] and Heating either combined or isolated. Throughout this period, gas exchanges analyzes were performed. At the end, morphological analyzes and curves of response to light and CO2 were realized, as well as, plant material was harvested for biochemical and anatomical analyzes. The results showed lower growth in response to environmental warming, associated with metabolic changes such as reductions in leaf levels of fructose and starch. On the other hand, increased [CO2] contributed positively to growth and plant biomass accumulation. Plant exposure to these two factors simultaneously resulted in [CO2] mitigation of the negative effects caused in response to plant warming. Therefore, it was possible to conclude that in a global climatic changes scenario, with increase in both [CO2] and atmospheric temperature, metabolic acclimation responses would occur and contribute to the maintenance of seedling growth.