Crambe is an oilseed plant whose oil is suitable for various industrial purposes, such as production of biodiesel, plastics, rubbers, and cosmetics. There are reports of the rusticity of this species and its potential for growth in arid and semi-arid environments, where water scarcity and soil salinity are common. However, studies regarding the tolerance of its seeds to these stresses and the physiological responses triggered during germination and seedling establishment under these conditions are incipient. The objective of this study was to evaluate the tolerance of crambe seeds to water deficit and salt stress during germination and early seedling development, as well as to investigate the role of antioxidant enzymes on tolerance to these conditions. The seeds were exposed to water and salt stresses and their performance was analyzed. Seed water content, imbibition rate, percentage and speed of germination, and the base water potential for seed germination were evaluated. In the seedlings, the following measurements were made: root and shoot length, fresh and dry matter of roots and shoots, moisture content, and activity of the enzymes superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX). Water deficit and salt stress reduce the water uptake rate of the seeds, the germination and growth of seedlings. The crambe seeds had higher tolerance to salt stress than to water deficit. Absorption of salt and the action of the SOD and CAT antioxidant enzymes are part of the tolerance mechanisms of crambe seeds to salt stress.

-Resistant lines can be identified by marker-assisted selection (MAS), based on alleles of genetic markers linked to the resistance trait. This reduces the number of phenotypically evaluated lines, one of the limitations in the development of cultivars with resistance to soybean cyst nematode (SCN). This study evaluated the efficiency of microsatellites near quantitative trait loci (QTL) for SCN resistance, in the linkage groups (LG) G and A2 of soybean, for the selection of resistant genotypes in populations originated from crosses between the cultivars Vmax and CD201. The QTL of LG A2 was not detected in 'Vmax' (derived from PI 88788). In MAS, the microsatellites ofLG G were efficient in selecting F 6:7 families with resistance and moderate resistance to SCN race 3. The selection efficiency of the microsatellites Sat_168, Satt309 and Sat_141 was greater than 93%.

Crambe’s breeding is still incipient, with few cultivars of interest. The aims of the present study were: i) to evaluate the divergence between 10 genotypes of crambe, through morphoagronomic and quality traits, using multivariate analyses; and ii) to estimate genetic parameters related to these traits. The trial was conducted in a greenhouse, and the experimental data were submitted to multivariate analysis and genetic evaluation. The genotypes differed significantly among them for plant height (PH), stem diameter (SD), number of branches per plant (NB), height of the first productive branch (HPB), mass of 1000 grains (M1000), grain yield (YIELD) and oil productivity (OIL). The experimental coefficient of variation revealed good precision (4.29 to 13.81%). The averages of YIELD (1936.94 kg/ha) and OIL (660.10 kg/ha) were high. The traits presented high estimates of broad-sense heritability on a mean genotype basis (h2 > 73.65). The cluster analysis revealed five clusters of genotypes. YIELD showed the greatest contribution (22.31%) to the diversity among the genotypes, followed by HPB, NB and SD. Genotypes 2 and 4 can be used as parents at future crosses, as they are promising in obtaining segregant populations.

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