02005naa a2200277 a 450000100080000000500110000800800410001902400580006010000200011824501110013826000090024952011750025865300170143365300200145065300170147070000180148770000200150570000180152570000180154370000200156170000190158170000200160070000170162070000160163777300740165319372792021-11-03       2012    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1111/j.1365-2389.2012.01439.x2DOI1 aCANELLAS, L. P.  aChemical properties of humic matter as related to induction of plant lateral roots.h[electronic resource]  c2012  aA series of humic matter samples isolated from a soil sequence, different oxisols, size-fractionated from avermicompost humic acid and subjected to chemical modifications, were characterized by CPMAS13C-NMRspectroscopy. The relative signal areas in chemical shift regions of NMR spectra of the four sets of sampleswere analysed by principal component analysis (PCA). Hierarchical cluster analysis (HCA) was applied tobuild a classification model, which allowed the recognition of humic matter according to its origin. Therelationship between carbon species and biological activity of humic acids, as promoters of lateral rootemergence, was obtained by applying PLS multivariate analysis. This showed that lateral root emergencewas mostly related to NMR parameters such as the hydrophobicity index (HB/HI) and the 40 - 110 and160 - 200 ppm chemical shift regions (hydrophilic carbon HI), while the content of hydrophobic (HB) carbon inhumic samples was negatively correlated with induction of lateral root hair. Our results represent a step furtherin the structure-bioactivity relationship of natural humic substances and confirm their role as plant root growthpromoters.  aHumic matter  aHumic substance  aVermicompost1 aDOBBSS, L. B.1 aOLIVEIRA, A. L.1 aCHAGAS, J. G.1 aAGUIAR, N. O.1 aRUMJANEK, V. M.1 aNOVOTNY, E. H.1 aOLIVARES, F. L.1 aSPACCINI, R.1 aPICCOLO, A.  tEuropean Journal of Soil Sciencegv. 63, n. 3, p. 315-324, Jun. 2012.