Chlorophyll Meter and Stalk Nitrate Techniques as Complementary Indices for Residual Nitrogen

Chlorophyll Meter and Stalk Nitrate Techniques as Complementary Indices for Residual Nitrogen

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...

Chlorophyll Meter Assessments of Corn Response to Nitrogen Management Practices

NOTES & UNIQUE PHENOMENA Using a Nitrate Specific Ion Electrode to Determine Stalk Nitrate-Nitrogen Concentration

The end-of-season stalk NO, test has been used to determine N sufficiency in corn (Zea mays L.). Nitrate concentration is commonly determined with flow-injection analysis (FIA), which is accurate but uses hazardous chemicals and is time-consuming. Use of a simpler method of NO, determination, such as the NO, specific ion electrode (SIE), may save time and costs, and reduce hazards. The objectiv...

Predicting Nitrogen Fertilizer Needs for Sugarbeets from Residual Nitrate and Mineralizable Nitrogen'

Received for publication ply 8, 1974 Nitrogen (N) fertilizer management for sugarbeet (Beta vulgaris L.) production requires more precise information than for most crops. Inadequate N limits plant growth and root yield, but excess N may reduce both sucrose percentage and recoverable sucrose (7)." Also, excess N may stimulate more leaf growth than necessary. The rate and timing of N fertilizer a...