| Title: | Light reflectance compared with other nitrogen stress measurements in corn leaves. |
| Authors: | Blackmer, T.M.
Schepers, J.S.
Varvel, G.E.
USDA, ARS |
| Source: | Agronomy journal. Nov/Dec 1994. v. 86 (6), p. 934-938. |
| NALT Subjects: | Zea mays
nutrient deficiencies
nitrogen
detection
measurement
leaves
reflectance
light
fertilizer requirements |
| Other Subjects: | light relations
fertilizer requirement determination |
| Issue Date: | Nov-1994 |
| Abstract: | New tools that can rapidly quantify the N status of corn could be valuable in N fertilizer management practices This study was conducted to compare light reflectance from corn leaves with other parameters used to detect N deficiency. Light reflectance (400-700 nm) as measured from corn leaves in the laboratory with a Hunter tristimulus colorimeter was compared with Minolta SPAD 502 chlorophyll meter readings (light transmittance at 650 and 940 nm), leaf N concentrations, and specific leaf N (N content per unit area). Measurements were made on individual ear leaves collected from an irrigated corn N response trial with four hybrids and five N treatments. Light reflectance near 550 nm was the best wavelength to separate N treatment differences. Reflectance at 550 nm provided a stronger relationship with both leaf N concentration and chlorophyll meter readings than between chlorophyll meter readings and leaf N concentration. The measurement of light reflectance near 550 nm has promise as a technique to detect N deficiencies in corn leaves. |
| URI: | http://hdl.handle.net/10113/16820 |
| Appears in Collections: | USDA Research and Information
|
