•  
  •  
 

Keywords

corn, nitrogen sensing, SPAD meter, nitrogen sufficiency index, leaf nitrogen concentration

Abstract

The Soil Plant Analysis Development (SPAD) meter is a sensor widely utilized as an indirect method to monitor nitrogen (N) status in various crops. However, the sensor’s accuracy can be affected by environmental and crop-specific factors. This study aimed to investigate the utility of employing the SPAD to monitor N in corn leaves at different growth stages, using the Nitrogen Sufficiency Index (NSI). For this reason, a trial was conducted in Topeka, KS (US), during the 2023 growing season featuring twelve treatments with varied N levels, rates, and fertilization timings. The study analyzed the relationship between 1) SPAD meter readings and leaf N concentration (Nc), and 2) Nc, NSI, and corn grain yield at V6, V10, V14, and R1 crop growth stages. The Nc was positively correlated with grain yield at V14, particularly at R1 when Nc accounted for most yield variations. The results suggest that the NSI approach, implemented via the SPAD meter from the V10 growth stage onward, serves as an effective predictor for estimating the Nc.

Download
COinS
 

Rights Statement

In Copyright - Educational Use Permitted.
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.