Gas exchange and water relations responses to drought of fast- and slow-growing black spruce families
- 1 October 1997
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Botany
- Vol. 75 (10) , 1700-1706
- https://doi.org/10.1139/b97-884
Abstract
To determine how different mechanisms of drought tolerance contribute to growth rate under drought, this study compared four full-sib black spruce (Picea mariana (Mill.) B.S.P.) families which differed in growth rate when soil water became limiting, stomatal conductance, photosynthesis, and water relations responses to drought. Repeated drought cycles were imposed by withholding soil water in a nursery and physiological responses were measured near the end of the first and third cycle. The most vigorous family under drought had greater osmotic adjustment and maintained higher rates of net photosynthesis during the first cycle of drought and resumed higher rates of photosynthesis sooner upon stress relief, compared with two slow-growing families. Pressure–volume analysis of drought-stressed shoot tissues indicated that the fast-growing family exhibited a larger degree of elastic enhancement (i.e., decrease in bulk modulus of elasticity), which would explain its higher turgor pressure, compared with the two less vigorous families. However, family differences in gas exchange and water relations largely diminished when seedlings were exposed to repeated cycles of drought. Therefore, fast-growing black spruce families under drought may gain selective growth advantage by a better ability to tolerate, rather than postpone, momentary dehydration. Short-term screening trials could be used to detect drought tolerant genotypes in black spruce. Key words: drought, family variation, photosynthesis, Picea mariana, stomatal conductance, water relations.Keywords
This publication has 14 references indexed in Scilit:
- Effects of nitrogen limitation on water relations of jack pine (Pinus banksiana Lamb.) seedlingsPlant, Cell & Environment, 1995
- Drought tolerance in faster‐ and slower‐growing black spruce (Picea mariana) progenies: II. Osmotic adjustment and changes of soluble carbohydrates and amino acids under osmotic stressPhysiologia Plantarum, 1992
- Drought tolerance in faster‐ and slower‐growing black spruce (Picea mariana) progenies: I. Stomatal and gas exchange responses to osmotic stressPhysiologia Plantarum, 1992
- Effects of repeated stress on turgor pressure and cell elasticity changes in black spruce seedlingsCanadian Journal of Forest Research, 1991
- Sensing of soil water status and the regulation of plant growth and developmentPlant, Cell & Environment, 1990
- Changing concepts regarding plant water relationsPlant, Cell & Environment, 1988
- A diallel cross in black spruceGenome, 1987
- A Comparison of Pressure-Volume Curve Data Analysis TechniquesJournal of Experimental Botany, 1985
- Environmental control of leaf water conductance in conifersCanadian Journal of Forest Research, 1976
- Evaluation of Water Stress Control with Polyethylene Glycols by Analysis of GuttationPlant Physiology, 1971