Effects of nitrogen application rates on the spatio-temporal variation of leaf SPAD readings on the maize canopy

Abstract The spatio-temporal variation of leaf chlorophyll content is an important crop phenotypic trait that great significance for evaluating productivity. This study used a soil-plant analysis development (SPAD) meter non-destructive monitoring dynamics to characterize the patterns in nutritional status maize ( Zea mays L.) leaves under three nitrogen treatments two cultivars. results showed levels could affect maximum SPAD reading max ) and duration high reading. A rational model was measure changes readings over time single leaves. suitable predicting nutrient each position different treatments, parameter values were dependent. at decreased with reduction supply. Leaves positions both cultivars responded differently higher rates. Lower (8th–10th positions) more sensitive than other response nitrogen. Monitoring dynamic lower accurately assess supply plants. nitrogen-deficient plants had shorter compared nitrogen-sufficient plants; this physiological mechanism should be studied further. In summary, plant analysed determine critical potentially assisting identification appropriate agronomic management practices, such as adjustment rates late fertilization.