Genetic Variation in Nitrogen Use Efficiency of Loblolly Pine Seedlings
Abstract:Seedlings of 23 open-pollinated loblolly pine (Pinus taeda L.) families were grown in a greenhouse at two nitrogen (N) levels (5 and 50 ppm). Differences among families for components of N use efficiency (NUE) were evaluated from measurements of biomass and N accumulation in different parts of seedlings. NUE, defined as stem biomass produced per unit of N applied, was partitioned into two major components: uptake and utilization efficiencies. Family differences were detected for NUE and its two components at low N and for utilization efficiency at high N. Heritability estimates indicated that NUE traits were under a moderate to high degree of genetic control. NUE and its components were generally positively correlated with root and shoot growth of seedlings. Families with more nitrogen (high uptake efficiency) had greater root length and stem height at low N but not at high N. Strong correlation of seedling root and shoot traits with NUE components indicated that genetic differences in N use may reflect differences in seedling growth. The relative contribution of uptake or utilization efficiency to the variation in NUE was different at the two N levels. At the high N level, differences among families for NUE were due largely to variation in utilization of absorbed N, while uptake and utilization efficiencies contributed equally to the variation in NUE at the low N level. Furthermore, some families with similar levels of NUE showed large differences in the relative contribution of uptake and utilization efficiency. For. Sci. 37(2):613-626.
Document Type: Journal Article
Affiliations: Associate Professor, Department of Forestry, North Carolina State University, Raleigh, NC, 27695-8002
Publication date: June 1, 1991
More about this publication?
- Forest Science is a peer-reviewed journal publishing fundamental and applied research that explores all aspects of natural and social sciences as they apply to the function and management of the forested ecosystems of the world. Topics include silviculture, forest management, biometrics, economics, entomology & pathology, fire & fuels management, forest ecology, genetics & tree improvement, geospatial technologies, harvesting & utilization, landscape ecology, operations research, forest policy, physiology, recreation, social sciences, soils & hydrology, and wildlife management.
Forest Science is published bimonthly in February, April, June, August, October, and December.
2015 Impact Factor: 1.702
Ranking: 16 of 66 in forestry
Also published by SAF:
Journal of Forestry
Other SAF Publications
- Submit a Paper
- Membership Information
- Author Guidelines
- Ingenta Connect is not responsible for the content or availability of external websites