Brassica carinata nutrient accumulation and partitioning across maturity types and latitude

Abstract

As a recently introduced crop in the United States, there are limited data regarding temporal nutrient accumulation and partitioning dynamics of Brassica carinata (carinata). A four site-year study was conducted in Jay, FL and Salisbury, NC during the 2018–2019 and 2019–2020 growing seasons. Three carinata genotypes (DH-157.715, M-01, and Avanza 641) proposed by the industry to represent early-, mid-, and full-season genotypes, respectively, were sampled at multiple growth stages and partitioned into leaves, stems, reproductive parts (flowers plus pods), and seed to determine biomass and nutrient accumulation across three genotypes in Florida and one full season genotype in North Carolina. Averaged over two site-years and genotypes in Florida, accumulation (per ha) of 169 kg N, 22 kg P, 160 kg K, 58 kg S, 475 g Zn, and 218 g B was required to produce 1635 and 10,872 kg ha−1 of seed yield and biomass, respectively. Nutrients with high harvest index values included P (60%), N (55%), S (32%), and Mg (29%). Averaged over two site-years in North Carolina, accumulation (per ha) of 178 kg N, 26 kg P, 87 kg K, 24 kg S, 416 g Zn, and 127 g B produced 2428 and 9102 kg ha−1 of seed yield and biomass, respectively. Nutrients with greatest harvest index values were P (57%), N (50%), S (32%), and Mg (26%). Internal efficiency of N, P, and K, measured as slopes of seed yield regressions over nutrient uptake across all genotypes and locations were 16, 83, and 8 kg seed yield per kg N, P, and K uptake, respectively. These results describe temporal nutrient accumulation and partitioning in carinata and are critical to refine nutrient management strategies and guide fertilizer application decisions.