Relationships between chlorophyll meter readings and leaf chlorophyll concentration, N status, and crop yield: A review 1

作者：C. W. Wood, D. W. Reeves, David G. Himelrick · 年份：1993 · 被引用次数：187 · 研究领域：Soil Carbon and Nitrogen Dynamics、Plant Water Relations and Carbon Dynamics、Plant nutrient uptake and metabolism

Prediction of crop nitrogen (N) requirements is necessary for efficient fertilizer N utilization and protection of groundwater against contamination. Soil tests for available N have been successful in predicting crop N needs in arid regions, but have met with less success in humid regions. Tissue tests have shown promise for crop N requirement prediction, but time required for sampling and laboratory analyses may disallow timely producer response to crop N deficiencies. Recently, hand-held chlorophyll meters, which measure crop leaf green color intensity, have become available. Since green color intensity of crop leaves is directly related to crop N status, chlorophyll meters may have utility in prediction of crop N requirements. Research on chlorophyll meter use has been conducted for a variety of crops including rice (Oryza sativa L.), maize (Zea mays L.), wheat (Triticum aestivum L.), and cotton (Gossypium hirsutum L.), and horticultural crops. These studies have shown high correlations between chlorophyll meter readings and extractable leaf chlorophyll, as well as high correlations between chlorophyll meter readings and crop N status. Some research has identified critical chlorophyll meter reading levels that allow confirmation of N responsive sites. However, identification of appropriate N rates with chlorophyll meters at N responsive sites is more difficult at this time. Moreover, chlorophyll meter readings for a particular crop N status likely vary with crop varieties,...