Tolerância de mudas clonais a diferentes condições hídricas

Abstract

The increase in energy demand boosted Brazil to seek new sources of energy to meet the growing demand of the country. And the use of planted forests for energy purposes has stood out as a promising alternative, for being a source of generating clean, renewable energy. Eucalyptus forests have been highlighted as the most planted in the world, for being the most productive. However, due to the need for increased productivity's survey was conducted in order to assess the effects of different water conditions on the growth and physiology of eucalyptus clonal seedlings, focusing on the production of biomass for energy generation. This research was developed in the greenhouse, in the laboratory of plant physiology and forest seedlings, in the center of Agrarian Sciences (ECSC) in the Universidade Federal de Alagoas (UFAL), between the months of July to November 2015, with 120-day trial period. Eucalyptus clonal seedlings were used. The seedlings have undergone a process of transplanting, which were cultivated for a period of 60 days for acclimatization. The experimental design was completely randomized design (DIC), the treatments were arranged in factorial 3 x 2 system consisting of three clonal seedlings (144, 1407 and u 865) and two water conditions 75% of field capacity and 100% of field capacity, with five repetitions. To accompany the growth were measured weekly variables (height, number of leaves and stem diameter of clonal seedlings). At the end of the experiment evaluated the production and dry matter allocation of parts areas and roots and root/shoot ratio. Also at the end of the experiment was evaluated the issue of chlorophyll a fluorescence, at noon (Fv/Fm and Yield) and the chlorophyll content in third leaf fully developed, using the portable light modulated Fluorômetro ... and SPAD and by biochemical method. The data were subjected to analysis of variance using the software Assistat, averages were compared with each other by Tukey test at 5% probability. It can be observed that the water condition 100% of field capacity occurred significant differences for all variables, growth and production and rental of biomass, there was also a reduction of the quantum efficiency of photosystem II,green intensity of leaves(Spad) readings and chlorophyll a, chlorophyll b, total chlorophyll and carotenoid. Showed that the water condition 75% of field capacity clonal seedlings developed better. The data indicates that the clone was i144 which had less tolerance for water condition 100% of field capacity, the clones and 1407 865 were those who had a higher tolerance for water condition 100% of field capacity.