Baseline for <i>Brassica carinata</i> Components of Nitrogen-Use Efficiency in Southern South America

Abstract

Biofuels play an important role in the reduction of greenhouse gas emissions, but their production results in greenhouse gases such as nitrous oxide (N2O), mainly from nitrogen (N) fertilization. Brassica carinata (carinata) is an unexplored winter crop in the world’s main cropping areas, with multiple applications (cover crop, jet biofuel, and animal feed, among others). We analyzed a set of on-farm fertilization experiments (2016–2018) in southern South America using quantile regression to establish a baseline for both seed yield (YSEED) and the different components of nitrogen-use efficiency (NUE). Maximum YSEED for the 50th and 90th percentiles ranged from 2.5 to 3.5 Mg ha−1, with a N availability of 150–160 kg ha−1 (soil + fertilization). The NUE ranged from 3 to 13 kg seed per kg of N available. Carinata, in the absence of other limiting factors, had a high N uptake (NUPT) capacity (1.0 to 1.5 kg ha−1 NUPT per kg ha−1 N available [soil + fertilization]). The explored N fertilization rates had no significant influence on oil concentrations (455 to 517 g kg−1) and protein concentrations (192 to 253 g kg−1). The region has a high potential for carinata production, with a high capacity to take up available N.

Keywords

• Brassica
• nitrogen fertilization
• bioenergy crop
• seed yield
• nitrogen uptake efficiency
• nitrogen-utilization efficiency