Crambe: Seed yield and quality in response to nitrogen and sulfur-a case study in Northeastern Poland

Abstract

The aim of this study was to determine the effect of nitrogen (0, 30, 60, 90, 120 kg ha−1) and sulfur (0, 15, and 30 kg ha−1) fertilization on the morphometric parameters of plants, seed yield components, seed and straw yield, N fertilizer use efficiency (NFUE), and quality of crambe seeds. The experiment had a randomized complete block design, and it was carried out in Bałcyny (northeastern Poland) in 2017-2019. In northeastern Poland, the average seed yields ranged from 0.96 to 1.64-1.82 Mg ha−1 (hulled seeds). Seed yield increased significantly in response to 120 kg N ha−1 and 15 kg S ha−1. The NFUE of crambe decreased by 28% with a rise in N rate. Hulled crambe seeds accumulated 324-394 g kg−1 DM of crude fat, 208-238 g kg−1 DM of total protein, and 118-137 g kg−1 DM of crude fiber. Nitrogen fertilization decreased the crude fat content (by 6%), and it increased the total protein content (by 11%) and the crude fiber content (by 14%) of crambe seeds. Sulfur fertilization increased crude fat content (by 4-5%) without inducing significant differences in the total protein content and the crude fat content of seeds.