Differential chemical allocation and plant adaptation: A Py-MS Study of 24 species differing in relative growth rate

Abstract

The chemical composition of leaves of 24 wild species differing in potential relative growth rate (RGR) was analysed by pyrolysis-mass spectrometry. The variation in RGR significantly correlated with differences in chemical composition: slow-growing species were richer in glucan-based polysaccharides and in C 16:0 fatty acid, whereas fast growing ones contained more protein (other than those incorporated in cell walls) and chlorophyll, sterols and diglycerides. Other, apparently significant correlations, e.g. for pentose-based hemicellulose and for guaiacyl lignin appeared solely based on a group separation between mono-and dicotyledonous species.Considering the eleven monocotyledonous and thirteen dicotyledonous species separately, correlations were found in addition to the previously mentioned general ones. Within the group of the monocotyledons the low-RGR species were significantly enriched in pentose-based hemicellulose, ferulic acid and (hydroxy)proline-rich cell wall protein and nearly significant in guaiacyl and syringyl lignin, fast-growing species contained more potassium. Within the group of the dicotyledons slow-growing species were enriched in triterpenes and aliphatic wax esters.In general, the monocotyledons contained more cell wall material such as pentose-based hemicellulose, ferulic acid, glucans (including cellulose) and guaiacyl-lignin, and also more aliphatic wax esters, than the dicotyledons. The dicotyledons, on the other hand, contained somewhat more protein than the grasses.Per unit weight of cell wall, the amount of (hydroxy)proline-rich protein in low-RGR species was comparatively low. A higher investment of cell wall proteins to explain the low rate of photosynthesis per unit of leaf nitrogen of slow-growing species as suggested by Lambers and Poorter (1992), therefore, seems unlikely.Abbreviations: HPRP-(hydroxy)proline-rich protein(s), L A R -leaf area ratio, L W R -leaf weight ratio, MVAmultivariate analysis, NAR-net assimilation rate, P C -principal component, PNUE-photosynthetic nitrogen use efficiency, PyGCMS-pyrolysis -gas chromatography-mass spectrometry, PyMS-pyrolysis mass spectrometry, R G R -relative growth rate, SLA-specific leaf area, SLM -specific leaf mass

Changes in chemical composition related to fungal infection and induced resistance in carnation and radish investigated by pyrolysis mass spectrometry

“…For proteins we recently published a number of marker fragment ions [43 ] additional to specific ones such as presented before [37,39,40 ]. In the present work major changes in proteins were not found.…”

“…Part of the monoses may also have been derived from glycolipids and\or glycoproteins. Their contribution, however, is comparatively small and, furthermore, in previous work [40 ] percentages of the total ion current of the polysaccharide markers mentioned correlated with the residual (hemi)-cellulose fraction from wet chemical analysis. Mass peaks m\z 31, 32, 43, and a couple of others are non-specific ions for polysaccharides.…”

“…Large compositional differences might also influence the type of fragmentation, especially when large variations in sodium and\or potassium concentration are involved [28 ]. The composition of the plant material investigated is rather similar, however, and for such material qualitative and quantitative determinations based on relative intensities of ions in PyMS [1,40,42,43 ] were shown to correlate well with wet chemical methods.…”

“…Quantitative determinations based on relative intensities of ions in PyMS are possible and have been shown to correlate well with conventional wet chemical methods [40,43,44 and their cited references]. Mainly, however, PyMS fragments are used as qualitative and semiquantitative markers.…”

“…Interpretation of PyMS spectra Lists of specific marker fragments for the different plant polymers and other constituents have been presented before [22,37,39,40,43 ]. Therefore, only the ions mentioned in the text and those shown in the figures are mentioned, and where necessary their validity as marker ion will be discussed.…”