Growth and water relations of black locust and pine seedlings exposed to controlled water stress

Abstract

Some responses of very young jack pine (Pinusbanksiana Lamb.), red pine (Pinusresinosa Ait.), and black locust (Robiniapseudoacacia L.) seedlings grown under constant water stress conditions induced by polyethylene glycol 4000 culture solutions were investigated. Seedlings grown under stressful conditions had lower leaf conductance, produced less foliar surface area, and accumulated less dry weight than nonstressed seedlings. Seedlings grown under nonstressed conditions were found to undergo considerable transpiration at night. When compared with the pines, black locust seedlings grew more rapidly, had lower (more negative) xylem pressure potentials, and showed poorer survival under the more stressful growth conditions.