Non-structural carbohydrates in woody plants compared among laboratories
Citation
Quentin, AG and Pinkard, EA and Ryan, MG and Tissue, DT and Baggett, LS and Adams, HD and Maillard, P and Marchand, J and Landhausser, SM and Lacointe, A and Gibon, Y and Anderegg, WRL and Asao, S and Atkin, OK and Bonhomme, M and Claye, C and Chow, PS and Clement-Vidal, A and Davies, NW and Dickman, LT and Dumbur, R and Ellsworth, DS and Falk, K and Galiano, L and Grunzweig, JM and Hartmann, H and Hoch, G and Hood, S and Jones, JE and Koike, T and Kuhlmann, I and Lloret, F and Maestro, M and Mansfield, SD and Martinez-Vilalta, J and Maucourt, M and McDowell, NG and Moing, A and Muller, B and Nebauer, SG and Niinemets, U and Palacio, S and Piper, F and Raveh, E and Richter, A and Rolland, G and Rosas, T and Saint Joanis, B and Sala, A and Smith, RA and Sterck, F and Stinziano, JR and Tobias, M and Unda, F and Watanabe, M and Way, DA and Weerasinghe, LK and Wild, B and Wiley, E and Woodruff, DR, Non-structural carbohydrates in woody plants compared among laboratories, Tree Physiology, 35, (11) pp. 1146-1165. ISSN 0829-318X (2015) [Refereed Article]
Non-structural carbohydrates (NSC) in plant tissue are frequently quantified to make inferences about plant responses to environmental
conditions. Laboratories publishing estimates of NSC of woody plants use many different methods to evaluate NSC. We asked
whether NSC estimates in the recent literature could be quantitatively compared among studies. We also asked whether any differences
among laboratories were related to the extraction and quantification methods used to determine starch and sugar concentrations.
These questions were addressed by sending sub-samples collected from five woody plant tissues, which varied in NSC content
and chemical composition, to 29 laboratories. Each laboratory analyzed the samples with their laboratory-specific protocols,
based on recent publications, to determine concentrations of soluble sugars, starch and their sum, total NSC. Laboratory estimates
differed substantially for all samples. For example, estimates for Eucalyptus globulus leaves (EGL) varied from 23 to 116 (mean = 56) mg g−1 for soluble sugars, 6–533 (mean = 94) mg g−1 for starch and 53–649 (mean = 153) mg g−1 for total NSC. Mixed model analysis of variance showed that much of the variability among laboratories was unrelated to the
categories we used for extraction and quantification methods (method category R2 = 0.05–0.12 for soluble sugars, 0.10–0.33 for starch and 0.01–0.09 for total NSC). For EGL, the difference between the highest
and lowest least squares means for categories in the mixed model analysis was 33 mg g−1 for total NSC, compared with the range of laboratory estimates of 596 mg g−1. Laboratories were reasonably consistent in their ranks of estimates among tissues for starch (r = 0.41–0.91), but less so for total NSC (r = 0.45–0.84) and soluble sugars (r = 0.11–0.83). Our results show that NSC estimates for woody plant tissues cannot be compared among laboratories. The relative
changes in NSC between treatments measured within a laboratory may be comparable within and between laboratories, especially
for starch. To obtain comparable NSC estimates, we suggest that users can either adopt the reference method given in this
publication, or report estimates for a portion of samples using the reference method, and report estimates for a standard
reference material. Researchers interested in NSC estimates should work to identify and adopt standard methods.
Item Details
Item Type:
Refereed Article
Keywords:
extraction and quantification consistency, non-structural carbohydrate chemical analysis, particle size, reference method, soluble sugars, standardization, starch
