The present study objective was identifying mechanisms of response to water deficit of paricá seedlings. The experiment was conducted in a greenhouse, in 8-liter pots, with substrate consisting of soil (dystrophic RedYellow Latosol), in randomized block design, with five different irrigations based on the evapotranspiration of the plants (20, 40, 60, 80 and 100%), with six replications. The plants were irrigated daily, with a water volume corresponding to 100% of the evapotranspired water, and, at 90 days after germination, subjected to ten days of water deficit, after that irrigated during ten days with the different percentages of evapotranspiration, then evaluated. The following variables were measured: number of leaves (NL), plant height (PH), stem diameter (SD), total biomass (TB), total daily transpiration (TDT), total chlorophyll (TC), carotenoids (CAR), root mass ratio (RMR), leaf mass ratio (LMR) stem mass ratio (SMR). Concluded that paricá seedlings response to water deficit with slowing down of dehydration, with reduction of content of carotenoids and increase in root volume. As a consequence of water stress, they reduce the number of leaves, stem diameter, plant height, and, of course, total biomass, aiming at maintaining the internal water, indicating low ability to tolerate stress.

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The objective of this work was to evaluate the effect of different concentrations of indole-3-acetic acid (IAA) applications, in three immersion times on the vegetative propagation of red mombin (Spondias purpurea), using the cutting technique. The experimental design was the completely randomized, with three replicates, in a factorial scheme (3 x 6), three different immersion periods (8, 16 and 24 seconds), in six concentrations (0, 2, 4, 6, 8 and 10 g L-1) of IAA, with ten cuttings per plot. The experimental period was 180 days and the characteristics percentage of cuttings survival, percentage of rooted cuttings, number of young shoots, number of roots per cuttings, general root length and total fresh mass. Data were submitted to analysis of variance by the F test and, later, fitted in regression equations. The vegetative propagation by red mombin cuttings was satisfactory to rooting and sprouting in the cuttings, with greater increases between the IAA concentrations of 6 to 10 g L-1. The 10 g L-1 concentration, in 24 seconds of immersion time, was the one that induced greater increases in the red mombin variables.

The objective of this work was to evaluate the effect of six indole-3-acetic acid (IAA) concentrations and three immersion times in IAA solutions on the vegetative propagation of Spondias dulcis and Spondias tuberosa by stem cuttings. The experiment was conducted in a greenhouse, using a completely randomized design, with a 6×3 factorial arrangement consisting of six indole-3-acetic acid concentrations (0, 2, 4, 6, 8, and 10 g L-1) and three immersion times (8, 16, and 24 seconds), with ten cuttings of S. dulcis and S. tuberosa per plot, and three replications. Percentage of surviving cuttings, and percentage of rooted cuttings, number of leaf buds, number of roots per cutting, root length, and total fresh weight were evaluated at 180 days after planting. Data were subjected to analysis of variance by the F test and to regression analysis. Vegetative propagation from woody cuttings of S. dulcis is not viable to produce seedlings, thus, new studies on this technique for this species are needed. Vegetative propagation from woody cuttings of S. tuberosa is satisfactory, but with low efficiency for improvement and emergence of new shoots and roots; it is more effective when using a concentration of 10 g L-1 of indole-3-acetic acid and immersion time in the solution of 16 seconds.

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