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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. Core Ideas: Nutrient acquisition for Brassica carinata as a winter crop was most rapid between pre‐bolting and flowering growth stage.Time and rate of nutrient acquisition varied among nutrients.Carinata genotypes with proposed variable maturity exhibited similar nutrient accumulation and partitioning. [ABSTRACT FROM AUTHOR]

Cowpea (Vigna unguiculata L. Walp) is a multipurpose crop widely cultivated in tropical and subtropical regions around the world. Characterizing cowpea phenotypes in germplasm collections is a crucial step to ensure future breeding efforts in the species. In this study, we estimated variance components and calculated genetic parameters for eight traits in 292 accessions from the University of California Riverside cowpea mini‐core collection, along with three lines released by the USDA, and seven cultivars. Broad‐sense heritability (H2) ranged from.21 to.83 for all accessions evaluated in Year 1, and from.16 to.83 for traits evaluated in 100 accessions during Year 2. Genotype × year correlations ranged from.45 to.99, illustrating consistency in phenotypic performance for some traits. Positive trait correlations were estimated for plant height and days to flowering, biomass at flowering (R1), and biomass at pod maturity (R6). Biomass at R1 and R6 were highly positively correlated. The USDA line US‐1137 showed high biomass production and can be used as forage and cover crop, whereas US‐1136, US 1138, and the cultivar Iron Clay showed superior traits as dual‐purpose (grain and/or fodder). Several accessions from the mini‐core outperformed cultivars and represent valuable genetic resources that can contribute to cowpea improvement. Moreover, these results showed that multiyear and/or multienvironment studies are needed to reliable select improved germplasm for agronomic traits. This study will provide cowpea breeders and geneticists with valuable phenotypic data to start new breeding efforts, and/or opportunities for gene discovery for key phenological and agronomic traits. Core Ideas: The UC‐Riverside mini‐core cowpea collection was phenotyped in Florida.Genetic parameters revealed large phenotypic diversity in this germplasm.Grain, forage, and multipurpose types were identified and selected.Accessions showed greater diversity than cowpea cultivars.The collection holds broad genetic diversity to improve cowpea productivity. [ABSTRACT FROM AUTHOR]