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Our hypothesis was that recovery responses (RI and RII) upon rehydration, after 1 and 8 d of moderate (WDI) and severe water deficit (WDII), are evidence of tolerance in two commercial bean cultivars, Tacarigua (T cv) and VUL-73-40 (V cv). Recovery of leaf water (Cw) and osmotic potentials (Cs), and relative water content (LRWC), showed strong dependence on soil water potential (sCw) followed by protein content; recovery connection between stomatal conductance and soil Cw is showed. Chlorophyll (a 'b), Ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco) activity, dry biomass (DM), and leaf area (LA) recovery were sensitive to WD intensity. Specific leaf area (SLA) and leaf density (D) recovery were less dependent on WD intensity and in time-dependent manner; V cv recovery was slower, showed faster recovery of Rubisco activity and DM due to slower recovery in SLA and D, which promoted it. Rubisco activity presented correlations with LRWC and Cw at moderate and severe WD in both cultivars, and significant correlation with Cs was observed in V cv. We conclude that recovery after rehydration reveals intrinsic tolerance to WD, due to an integration of metabolic and structural interactions, in responses to leaf water status components.

The ribulose-1,5-bis-phosphate (RBPC) CO fixation rate was measured at four different temperatures, 5°, 15°, 25° and 35° C, in three populations of Espeletia schultzii at different altitudes, 3100, 3550 and 4200 ma.s.l. The fixation rate increased with temperature increase in the populations studied. The population at 4200 m showed the higher rate at any temperature, followed by those at 3550 and 3100 m. The Km(CO) increased with temperature increase, but the values were similar among populations. The V values increased with temperature and were higher for the 4200-m population. These results suggest that the RBPC enzyme is more activated in the highland population and that the enzyme kinetics are not similar among populations.

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