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- Landhausser, S. M., et al.
(författare)
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Standardized protocols and procedures can precisely and accurately quantify non-structural carbohydrates
- 2018
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Ingår i: Tree Physiology. - : Oxford University Press (OUP). - 0829-318X .- 1758-4469. ; 38:12, s. 1764-1778
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Tidskriftsartikel (refereegranskat)abstract
- Non-structural carbohydrates (NSCs), the stored products of photosynthesis, building blocks for growth and fuel for respiration, are central to plant metabolism, but their measurement is challenging. Differences in methods and procedures among laboratories can cause results to vary widely, limiting our ability to integrate and generalize patterns in plant carbon balance among studies. A recent assessment found that NSC concentrations measured for a common set of samples can vary by an order of magnitude, but sources for this variability were unclear. We measured a common set of nine plant material types, and two synthetic samples with known NSC concentrations, using a common protocol for sugar extraction and starch digestion, and three different sugar quantification methods (ion chromatography, enzyme, acid) in six laboratories. We also tested how sample handling, extraction solvent and centralizing parts of the procedure in one laboratory affected results. Non-structural carbohydrate concentrations measured for synthetic samples were within about 11.5% of known values for all three methods. However, differences among quantification methods were the largest source of variation in NSC measurements for natural plant samples because the three methods quantify different NSCs. The enzyme method quantified only glucose, fructose and sucrose, with ion chromatography we additionally quantified galactose, while the acid method quantified a large range of mono- and oligosaccharides. For some natural samples, sugars quantified with the acid method were two to five times higher than with other methods, demonstrating that trees allocate carbon to a range of sugar molecules. Sample handling had little effect on measurements, while ethanol sugar extraction improved accuracy over water extraction. Our results demonstrate that reasonable accuracy of NSC measurements can be achieved when different methods are used, as long as protocols are robust and standardized. Thus, we provide detailed protocols for the extraction, digestion and quantification of NSCs in plant samples, which should improve the comparability of NSC measurements among laboratories.
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| 2. |
- Furze, Morgan E., et al.
(författare)
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Seasonal patterns of nonstructural carbohydrate reserves in four woody boreal species
- 2018
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Ingår i: Journal of the Torrey Botanical Society. - 1095-5674 .- 1940-0616. ; 145:4, s. 332-339
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Tidskriftsartikel (refereegranskat)abstract
- Plants store nonstructural carbohydrates (NSCs), such as sugars and starch, to use as carbon and energy sources for daily maintenance and growth needs as well as during times of stress. Allocation of NSCs to storage provides an important physiological strategy associated with future growth and survival, and thus understanding the seasonal patterns of NSC reserves provides insight into how species with different traits (e.g., growth form, leaf habit, wood anatomy) may respond to stress. We characterized the seasonal patterns of NSCs in four woody boreal plant species in Minnesota, USA. Sugar and starch concentrations were measured across the year in the roots and branches of two conifer trees, black spruce (Picea mariana (Mill.) B.S.P.) and eastern tamarack (Larix laricina (Du Roi) K. Koch), as well as in the leaves and branches of two evergreen broadleaf shrubs, bog Labrador tea (Rhododendron groenlandicum (Oeder) Kron & Judd) and leatherleaf (Chamaedaphne calyculata (L.) Moench). In general, seasonal variation was dominated by changes in starch across all organs and species. While similar seasonal patterns of NSCs were observed in the shrubs, different seasonal patterns were observed between the trees, particularly in the roots. Our results suggest that species-specific traits likely have consequences for organ-level storage dynamics, which may influence whole-plant growth and survival under global change
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