FOLIAR PHOTOPROTECTION IN EUCALYPTUS UNDER DIFFERENT ATMOSPHERIC DEMAND CONDITIONS

The evaluation of eucalyptus clones regarding gas exchange and growth measurements is necessary to make decisions that lead to higher production, reducing costs, and increasing water use efficiency, thus optimizing forest production.

The doctoral thesis work of the student Talita T. M. Xavier aimed to evaluate the initial growth of eucalyptus clones under conditions of different atmospheric demands associated with water stress. The experiments were conducted in two stages, in climate-controlled greenhouses with temperature and relative humidity control. Commercial clones of the hybrid Eucalyptus urophylla x Eucalyptus grandis at expedition age were studied, transplanted into 12-liter pots. The first study was developed with four, two microclimatic conditions (High atmospheric demand and Low atmospheric demand) and different irrigation intervals. The second study aimed to evaluate the use of a foliar photoprotector based on calcium carbonate in the growth of two clones under water stress.

In her research, Talita observed that the evaluated clones showed distinct growth patterns under different atmospheric demand conditions, especially when these conditions were associated with reduced water availability in the substrate, with all clones being penalized by water stress. High atmospheric demand acted as a stressful factor for initial growth of eucalyptus seedlings, however, the application of the foliar photoprotector favored growth, water status, and gas exchange of plants under water stress conditions with high atmospheric demand.

This type of research on the plant-environment interaction is extremely important for silviculture because, in addition to the challenges of mitigating the impact of climate change on commercially important forest species, it helps in decision-making in cultivation areas that are expanding into regions with hotter and drier climates. An interesting point revealed by the research is that the efficiency of the foliar photoprotector depends on atmospheric demand conditions.

More details can be found in the student's full thesis on our website and in the scientific articles published in the Journal of Forestry Research, Rev. Bras. Agric. Irrigada  Irriga