01666naa a2200277 a 450000100080000000500110000800800410001910000180006024500530007826000090013152009600014065300180110065300240111865300200114265300120116265300150117465300190118965300280120865300130123670000180124970000170126770000180128470000170130270000150131977300540133410394802005-09-12       2003    bl uuuu     u00u1 u    #d1 aALTLAND, J.E.  aRapid Determination of Nitrogen Status in Pansy.  c2003  aTwo experiments were conducted with pansy (Viola ×wittrockiana Gams ?Bingo Yello?) to determine the relationship between foliar nitrogen (% of dry weight) (FN) and either sap nitrate concentration (SN) in petioles or SPAD readings of foliage. FN was highly correlated to SN throughout both experiments (r = 0.80 to 0.91). FN was poorly correlated to SPAD readings early in both experiments (r = 0.54 to 0.65), but more highly correlated later when visual symptoms of N deficiency were apparent (r = 0.84 to 0.90). SN determined with the Cardy sap nitrate meter was a reliable predictor of FN in pansy, while SPAD readings were only reliable after symptoms of N deficiency were visually evident. FN can be predicted with SN using the following equation: log(SN) = 0.47*FN + 1.6 [r2 = 0.80, n = 132]. Growers and landscape professionals can use SN readings to predict FN levels in pansy, and thus rapidly and accurately diagnose the N status of their crop.  aAmor-perfeito  aCardy nitrate meter  aLandscape crops  aNitrate  aNitrogenio  aPlanta de vaso  aPotted plant production  aProducao1 aGILLIAM, C.H.1 aKEEVER, G.J.1 aEDWARDS, J.H.1 aSIBLEY, J.L.1 aFARE, D.C.  tHortscience, Alexandriagv.38, n.4, 2003. CD-ROM.