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ARS Home » Plains Area » Brookings, South Dakota » Integrated Cropping Systems Research » Research » Publications at this Location » Publication #203885
Title: Determining Nitrogen Nutrition and Yield of Canola through Existing Remote Sensing Technology

Author
item Osborne, Shannon

Submitted to: Agricultural Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/29/2006
Publication Date: 1/5/2007
Citation: Osborne, S.L. 2007. Determining Nitrogen Nutrition and Yield of Canola through Existing Remote Sensing Technology. Agricultural Journal. 2:180-184.

Interpretive Summary: Research evaluating the use of sensor-based technology for in-season nitrogen fertilizer applications has been of high priority due to environmental concerns. The majority of this work has been done on wheat and corn, with little research on other crops. A field study was established in Brookings, SD to evaluate the GreenSeeker Hand Held optical sensor (NTech Industries, Ukiah, CA) for measuring in-season N status on canola. Sensor readings and plant biomass samples were collected at four different intervals through the rosette to early bud growth stages. The sensor measures reflectance in the red and near infrared regions of the electromagnetic spectrum and calculates a normalized difference vegetation index (NDVI). The ability of the sensor readings to measure biomass, plant nitrogen uptake, and predict seed yield and protein for each sampling date was determined. In general, in-season plant biomass, plant nitrogen concentration, and seed yield increased with increasing nitrogen rate. Sensor readings (NDVI) showed a significant relationship with plant biomass, nitrogen uptake and seed yield regardless of sampling dates. Measurements collected in mid May resulted in the highest correlation with plant biomass, while the relationship increase with later sampling dates for yield. Results suggest that existing sensor-based variable nitrogen technology developed has the potential to be utilized for other non-traditional crops such as canola.

Technical Abstract: Over the past few decades there has been considerable research evaluating sensor-based technologies for in-season application of nitrogen (N). The majority of this work has been done on wheat (Triticum aestivum L.) and corn (Zea mays L.), with little research on other crops. A field study was established in Brookings, SD to evaluate the GreenSeeker Hand Held optical sensor (NTech Industries, Ukiah, CA) for measuring in-season N status on canola (Brassica napus L). Sensor readings and plant biomass samples were collected at four different intervals through the rosette to early bud growth stages. The sensor measures reflectance in the red and near infrared (NIR) regions of the electromagnetic spectrum and calculates a normalized difference vegetation index (NDVI). The ability of the sensor readings to measure biomass, plant N uptake, and predict seed yield and protein for each sampling date was determined. In general, in-season plant biomass, plant N concentration, and seed yield increased with increasing N rate. Sensor readings (NDVI) showed a significant relationship with plant biomass, N uptake and seed yield regardless of sampling dates. Measurements collected in mid May resulted in the highest correlation with plant biomass, while the relationship increase with later sampling dates for yield. Results suggest that existing sensor-based variable nitrogen technology developed has the potential to be utilized for other non-traditional crops such as canola.