Establishing dynamic thresholds for potato nitrogen status diagnosis with the SPAD chlorophyll meter

Comparison of petiole nitrate concentrations, SPAD chlorophyll readings, and QuickBird satellite imagery in detecting nitrogen status of potato canopies

Nitrogen (N) management is critical in optimizing potato yield and quality and reducing environmental pollution. Six N rates from 34 to 270 kg ha , and different timing of N application were used in a 3-year field experiment to contrast SPAD-502 chlorophyll meter and QuickBird satellite imagery data against the conventional petiole sampling technique for assessing canopy N status. Overall treat...

Chlorophyll meter – a decision-making tool for nitrogen application in wheat under light soils

Nitrogen (N) in plants is generally diagnosed by a soil test and plant tissue analysis.However, such analyses are costly in terms of time and money and are not easily accessible byresearchers and extension workers, let alone farmers. Alternative cost-effective methods arerequired for rapid analysis of the N status of crops and to guide N management in wheat. Theobjective of this study was to as...

Optimal Leaf Positions for SPAD Meter Measurement in Rice

The Soil Plant Analysis Development (SPAD) chlorophyll meter is one of the most commonly used diagnostic tools to measure crop nitrogen status. However, the measurement method of the meter could significantly affect the accuracy of the final estimation. Thus, this research was undertaken to develop a new methodology to optimize SPAD meter measurements in rice (Oryza sativa L.). A flatbed color ...

Chlorophyll Meter Assessments of Corn Response to Nitrogen Management Practices

World Congress of the International Commission of Agricultural and Biosystems Engineering (CIGR) NITROGEN ESTIMATION OF OILSEED RAPE USING SPAD AND VIS/NIR SPECTROSCOPY

The estimation of nitrogen status, non-destructively, in oilseed rape was performed using spectral reflectance with visible and near infrared reflectance spectroscopy (Vis/NIRS), and SPAD values of the oilseed rape leaves of 30 plots were measured by a SPAD 502 chlorophyll meter, and the research was carried out at experiment field in the Zhejiang University during growing season from 2007 to 2...