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Brassica carinata is grown as a winter crop in the Southeast United States and it is a non-edible oilseed feedstock for 'dropin' aviation and transportation fuels. The objective of this 2-yr study was to determine the effects of N application on dry matter (DM) production and the accumulation of nutrients in above-and belowground biomass. Carinata var. 110994EM was treated with four N rates (0, 45, 90, and 135 kg N ha-1) in 2014 and 2015 at Quincy, Florida. Above-and belowground biomass were collected and analyzed for macro-and micronutrients. The allocation of DM among root, leaves, stems, flowers/pods, and seed did not differ with N rate. Carinata was highly responsive to N with maximum yield (2798 kg ha-1) produced at 102.3 kg N ha-1 , while the economic optimum N rate occurred at 93 kg N ha-1. Maximum N uptake occurred between 50% bolting and 50% flowering while all other elements had maximum uptake between 50% flowering and pod formation. Nitrogen concentration in seed and straw increased with N rate. These results were attributed to the strong relationship between uptake and dry matter production. Total N uptake exceeded applied N by 11 to 160%, suggesting that carinata is highly efficient at scavenging and utilizing residual soil N. The identification of growth stages associated with maximum nutrient uptake may aid in aligning time of N application to critical growth stages corresponding to maximum N uptake. core Ideas • This is the first report of carinata dry matter accumulation and allocation responses to nitrogen. • Carinata growth, resource allocation, seed, and straw nitrogen concentration and uptake are highly responsive to nitrogen application in North Florida. • Dry matter accumulation increases with nitrogen rate; however, the allocation of dry matter to roots, leaves, stems, flower/pods and seeds are similar regardless of nitrogen rate. • Maximum nitrogen uptake occurred between 50% bolting and 50% flowering while all other elements had maximum uptake later in the season between 50% flowering and pod formation. • Total nitrogen uptake exceeded applied N by 11 to 160%, suggesting that carinata is highly efficient at scavenging and utilizing residual soil nitrogen. • Adequate nitrogen is required (93 kg N ha-1) for optimizing carinata productivity in sandy loam soils in North Florida.

Soybean [Glycine max (L.) Merr.] resistance to soybean rust (SBR) caused by Phakopsora pachyrhizi could reduce reliance on fungicides to manage this disease. The objective of this study was to identify soybean germplasm with resistance to field populations of P. pachyrhizi in the United States. Field evaluations of 576 accessions from the USDA Soybean Germplasm Collection for resistance to SBR were conducted at seven locations in the southern United States between 2006 and 2008. Accessions from maturity groups (MG) 000 to X and North American susceptible check cultivars from each MG except X were rated for disease severity in all year–location environments, and for disease incidence, fungal sporulation, lesion type, and/or uredinia density in certain environments. While none of the accessions was immune in all environments, 64 were resistant in two or more locations each year that they were tested. Some accessions appeared to be more resistant in certain environments than in others. Of the original four Rpp genes described in the literature, Rpp1 provided the highest level of resistance, and among the accessions with uncharacterized Rpp genes, PI 567104B had the highest overall resistance across environments. The plant introductions confirmed to be resistant in these evaluations should be useful sources of genes for resistance to North American populations of P. pachyrhizi