TY - JOUR
T1 - Evaluation of the Minolta SPAD-502 chlorophyll meter for nitrogen management in corn
AU - Bullock, D. G.
AU - Anderson, D. S.
PY - 1998
Y1 - 1998
N2 - The field study investigated the relationship of Minolta SPAD 502 (SPAD) readings to applied nitrogen (N) fertilizer rate, corn (Zea mays L.) yield, and leaf N concentration. The experiment was conducted on a total of six sites in Illinois during 1991 and 1992. Ten different open pedigree corn hybrids were grown at a final population of 65,000 plants ha-1. Nitrogen was applied at four rates (0, 90, 180, and 270 kg N ha-1) as 28% liquid N solution. Significant main effects of environment (E), and hybrid (H), and E x H interaction were detected for all measured parameters. SPAD readings and learn concentration at all sampling times (V7, R1, and R4) as well as grain N concentration were affected by N fertilizer rate. Maximum mean grain yield and maximum grain N concentration were obtained at 110 and 195 kg N ha-1, respectively. At all sampling times the correlation of SPAD readings to N fertilizer rate were low but significant (R=0.22 at V7 and R1, R=0.11 at R4). SPAD correlation to corresponding leaf N concentration improved over time. The Pearson correlation was R=0.33 at V7 and increased to R=0.78 at R4. The SPAD meter did a good job at providing a measure of the relative greenness of living leaves at a specific point in time. Chlorophyll readings can therefore be useful in detecting N deficiencies in growing crops. But, the SPAD meter cannot be used to make accurate predictions of how much fertilizer N will be needed by a crop during the future growing season. We conclude then that the SPAD meter will be most useful as a diagnostic aid rather than a tool for N management in corn.
AB - The field study investigated the relationship of Minolta SPAD 502 (SPAD) readings to applied nitrogen (N) fertilizer rate, corn (Zea mays L.) yield, and leaf N concentration. The experiment was conducted on a total of six sites in Illinois during 1991 and 1992. Ten different open pedigree corn hybrids were grown at a final population of 65,000 plants ha-1. Nitrogen was applied at four rates (0, 90, 180, and 270 kg N ha-1) as 28% liquid N solution. Significant main effects of environment (E), and hybrid (H), and E x H interaction were detected for all measured parameters. SPAD readings and learn concentration at all sampling times (V7, R1, and R4) as well as grain N concentration were affected by N fertilizer rate. Maximum mean grain yield and maximum grain N concentration were obtained at 110 and 195 kg N ha-1, respectively. At all sampling times the correlation of SPAD readings to N fertilizer rate were low but significant (R=0.22 at V7 and R1, R=0.11 at R4). SPAD correlation to corresponding leaf N concentration improved over time. The Pearson correlation was R=0.33 at V7 and increased to R=0.78 at R4. The SPAD meter did a good job at providing a measure of the relative greenness of living leaves at a specific point in time. Chlorophyll readings can therefore be useful in detecting N deficiencies in growing crops. But, the SPAD meter cannot be used to make accurate predictions of how much fertilizer N will be needed by a crop during the future growing season. We conclude then that the SPAD meter will be most useful as a diagnostic aid rather than a tool for N management in corn.
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U2 - 10.1080/01904169809365439
DO - 10.1080/01904169809365439
M3 - Article
AN - SCOPUS:0031970889
SN - 0190-4167
VL - 21
SP - 741
EP - 755
JO - Journal of Plant Nutrition
JF - Journal of Plant Nutrition
IS - 4
ER -