Genotypic variation in C and N isotope discrimination suggests local adaptation of heart-leaved willow
| Autor: | Robert D. Guy, Raju Y. Soolanayakanahally, Yi Hu |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
0106 biological sciences
Willow Genotype Nitrogen Physiology Growing season Plant Science Biology 010603 evolutionary biology 01 natural sciences chemistry.chemical_compound Nitrate Ecosystem Local adaptation 2. Zero hunger Carbon Isotopes Nitrogen Isotopes δ13C Salix δ15N 15. Life on land biology.organism_classification Isotopes of nitrogen Agronomy chemistry 010606 plant biology & botany |
| Zdroj: | Tree Physiology. 42:32-43 |
| ISSN: | 1758-4469 |
| Popis: | Plants acquire multiple resources from the environment and may need to adjust and/or balance their respective resource-use efficiencies to maximize grow and survival, in a locally adaptive manner. In this study, tissue and whole-plant carbon (C) isotopic composition (δ13C) and carbon/nitrogen (C/N) ratios provided long-term measures of use efficiencies for water (WUE) and nitrogen (NUE), and a nitrogen (N) isotopic composition (δ15N)-based mass balance model was used to estimate traits related to N uptake and assimilation in heart-leaved willow (Salix eriocephala Michx.). In an initial common garden experiment consisting of 34 populations, we found population-level variation in δ13C, C/N ratio and δ15N, indicating different patterns in WUE, NUE and N uptake and assimilation. Although there was no relationship between foliar δ13C and C/N ratios among populations, there was a significant negative correlation between these measures across all individuals, implying a genetic and/or plastic trade-off between WUE and NUE not associated with local adaptation. To eliminate any environmental effect, we grew a subset of 21 genotypes hydroponically with nitrate as the sole N source and detected significant variation in δ13C, δ15N and C/N ratios. Variation in δ15N was mainly due to genotypic differences in the nitrate efflux/influx ratio (E/I) at the root. Both experiments suggested clinal variation in δ15N (and thus N uptake efficiency) with latitude of origin, which may relate to water availability and could contribute to global patterns in ecosystem δ15N. There was a tendency for genotypes with higher WUE to come from more water-replete sites with shorter and cooler growing seasons. We found that δ13C, C/N ratio and E/I were not inter-correlated, suggesting that the selection of growth, WUE, NUE and N uptake efficiency can occur without trade-off. |
| Databáze: | OpenAIRE |
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