Light Reflectance Compared with Other Nitrogen Stress Measurements in Corn Leaves

作者：T. M. Blackmer, James S. Schepers, Gary E. Varvel · 发表于：Agronomy Journal · 年份：1994 · DOI：10.2134/agronj1994.00021962008600060002x · 被引用次数：332 · 研究领域：Plant nutrient uptake and metabolism、Growth and nutrition in plants、Crop Yield and Soil Fertility

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 deficiencies. 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.