Answers morphological and physiological woody species under water stress in soil with and without addition of organic matter

• Autor(a) principal: Maria da AssunÃÃo Machado Rocha
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFC
• Texto Completo: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13169
• topic: seca; adubaÃÃo orgÃnica; potencial hÃdrico; trocas gasosas; nutriÃÃo; CIENCIA DO SOLO

The low availability of water in the soil is one of the most limiting factors to plants growth and survival. The objective of this work was to evaluate the responses of morphological and physiological processes in the early stage of growth of guanandi (Calophyllum brasilense Cambess), african mahogany (Khaya ivorensis A. Chev ) and oiti (Licania tomentosa (Benth) Fritsch) for the imposition of severe water stress and rehydration in soil with and without organic matters The experiment was conducted in a greenhouse at the Meteorological Station of the Department of Agricultural Engineering of the UFC , located in Fortaleza (CE). The experimental design was a complete randomized block, factorial 3 x 2 x 2, formed by three species (Guanandi, Mogno Africano and Oiti) two water regimes (irrigated and non- irrigated) and two levels of organic manure (with and without addition of organic matter), with five blocks and two plants per replication. Irrigation was suspended for 15 days on half of the plants , while the other half (controls ) received irrigation continuously. At the end of the stress period the plants were again irrigated for 15 days for determination of recovery, as the experiment lasted 30 days. The following evaluations were performed: gravimetric soil moisture (θ), leaf water potential (Ψw), plant growth, leaf gas exchange, relative chlorophyll index and leaf concentration of mineral nutrients. Drought stress decreased leaf water potential affecting growth, nutrient uptake and physiological responses of plants during the period of stress. And in the recovery period the plants recover turgor, but the recovery in growth, gas exchange and nutrient accumulation presented slower, suggests the these plants require a longer period of recovery. The addition of organic matter in the soil favored the retention of water allowing the water supply to the plants during water deficit by reducing the deleterious effects of water stress on growth, physiological functions and nutrient accumulation during stress. Whereas in the soil with this input period rehydration plants had a better recovery due to reducing the negative effects induced by water stress.