Do the Responses to Water Deficit Differ Among Provenance Within Pinus nigra Species?

The ability of forests to adapt to drought is an important issue. Planting species or provenances adapted to drought conditions requires a good understanding of physiological behavior. This study examined the water-deficit responses of 19 black pine provenances planted in a common garden at the southern edge of its range. Gas exchange and hydraulic characteristics were measured. Some provenances tend to avoid water deficit by early stomatal control. An increase in specific hydraulic conductivity of sapwood and leaves was noted in other provenances. However, other provenances showed a very late transpiration control. Thus, the results showed significant differences between provenances in coping with drought conditions among black pine provenances, indicating genetic control of these parameters.