Abstract
ABSTRACTThe relationship among water use efficiency (WUE), productivity and carbon isotopic composition (δ13C) in white spruce (Picea glauca (Moench) Voss) seedlings was investigated. Sixteen hundred seedlings representing 10 controlled crosses were planted in the field in individual buried sand‐filled cylinders. The soil water content in the cylinders was measured using time domain reflectometry over two growing seasons and seedling water use determined by water balance. Two watering treatments were imposed: irrigation and dry land. There was significant (1.6–2.0%c) genetic variation in needle δ13C. Ranking of crosses in terms of δ13C was generally maintained over watering treatments and there was not a significant genetic versus environmental interaction. There was a positive correlation between δ13C and both intrinsic and long‐term WUE (more positive δ13C with increased WUE) and between δ13C and productivity, suggesting a correlation due to variation in photosynthetic capacity. Root to shoot ratios did not increase in water‐stressed plants, indicating that responses to drought were primarily at the level of gas exchange, rather than through morphological changes. Our results indicate that it should be possible to use δ13C as a surrogate for WUE and to select white spruce genotypes for high WUE without compromising yield.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.