01852naa a2200229 a 450000100080000000500110000800800410001902400350006010000140009524501300010926000090023950000570024852011220030565000120142765000200143965000090145965000140146865300140148265300200149670000180151677300880153410354902019-09-30       2002    bl uuuu     u00u1 u    #d7 a10.1017/S00218596020026052DOI1 aMORON, A.  aDetermination of macro elements in alfalfa and white clover by near-infrared reflectance spectroscopy.h[electronic resource]  c2002  aArticle history: Revised MS received 19 August 2002.  aSummary: Near-infrared reflectance spectroscopy was used to assess the mineral composition of both alfalfa (Medicago sativa L.) and white clover (Trifolium repens L.). Alfalfa (n=230) and white clover (n=97) plant samples from different locations in Uruguay representing a wide range of soil types were analysed. The samples were scanned for reflectance in a NIRSystems 6500 monochromator (NIRSystems, Silver Spring, MD, USA). Predictive equations were developed using modified partial least squares (MPLS) with cross validation to avoid overfitting. The coefficients of determination in calibration (R_{\rm cal}^{2}) and the standard errors in cross validation (SECV) were 0·93 (SECV: 1·6), 0·95 (SECV: 1·3), 0·93 (SECV: 1·9), 0·88 (SECV: 2·7), 0·82 (SECV: 0·3) and 0·75 (SECV: 4·7) for alfalfa and 0·98 (SECV: 0·8), 0·52 (SECV: 0·8), 0·97 (SECV: 2·7), 0·83 (SECV: 3·1), 0·82 (SECV: 1·9) and 0·45 (SECV: 2·6) for white clover, for N, Ca, K, P, Mg and S in g/kg on a dry weight respectively. Calcium, nitrogen and potassium were well predicted by NIRS in both alfalfa and white clover samples.  aCALCIUM  aMEDICAGO SATIVA  aNIRS  aPOTASSIUM  aMAGNESIUM  aMINERAL CONTENT1 aCOZZOLINO, D.  tJournal of Agricultural Science, December 2002, Volume 139, Issue 4, pages 413-423.