This work aimed to evaluate gas exchange, dry matter yield and biomass allocation in young aroeira plants submitted to water deficit. Three month-old seedlings of Schinus terebinthifolius Raddi were cultivated in containers containing 5.5 kg of soil. A completely randomized experimental design was used, with four water treatments (100%, 75%, 50% and 25% to field capacity-FC), with four replicates. Transpiration and diffusive resistance were evaluated at midday every seven days for 72 days. At the end of the experimental period, leaf (LDM), stem (SDM) and root dry matter (RDM) were all determined, biomass allocation of all the organs of the plants and root to shoot ratio (R/Sh) were also determined. Stomatal closure was observed in plants under 25% FC eleven days after water treatments. At this time, plants were watered once until 100% FC and watering was suspended until the plants reached 25%FC again until the end of the experimental period and did not show stomatal closure again. After being re-watered, plants were maintained at 25% FC, recovering stomatal aperture, which remained open until the end of the experimental period during this evaluation time. Plants under 75% FC produced more dry matter than those in the other treatments. Significant differences among treatments in biomass allocation were not observed. These results suggest that aroeira plant is moderately drought-tolerant at the young stage of development.
Schinus terebinthifolius; biomass allocation and transpiration
