Sensor‐based Nitrogen Fertilization for Midseason Rice Production in Southeast Missouri

Abstract

© 2017 American Society of Agronomy and Crop Science Society of America 5585 Guilford Rd., Madison, WI 53711. Sensor-based nitrogen (N) decision management tools have shown potential to improve N fertilizer efficiency, yield, and profitability. Small-plot experiments were conducted to evaluate the use of sensor- based management in guiding midseason N application decisions. Treatments were two rice (Oryza sativa L.) cultivars (Jupiter, a medium grain, and Roy J, a long grain) and eight N treatments: (i) check (no N fertilizer); (ii) 60 lb N/acre applied preflood + midseason N applied based on sensor reading (sensor-based management); (iii) 90 lb N/acre applied preflood + midseason N applied based on sensor reading (sensor-based management); (iv) 120 lb N/acre applied preflood; (v) 120 lb N/acre applied preflood + 30 lb N/acre applied at midseason (traditional practice); (vi) 120 lb N/acre applied preflood + midseason N applied based on sensor reading (sensor-based management); (vii) 150 lb N/acre applied preflood; and (viii) 180 lb N/acre applied preflood (N reference strip). Grain yield and nitrogen use efficiency (NUE) were compared among N treatments. Results showed sensor-based management for midseason application recommended lower total N application rate by 15 to 90 lb N/acre over the traditional practice. These results indicate that N fertilization made by a sensor-based midseason recommendation can optimize yield and NUE in southeast Missouri.