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The research was funded by FEDER funds (European Union), the Spanish Ministry of Science and Innovation (research project AGL2007-62834) and Dow Agrosciences LLC.

Seed meal amendments rich in glucosinolates are of interest for soil pest and disease control. The Ethiopian mustard (Brassica carinata A. Braun) line N2-6215, with very high levels of seed glucosinolates (160 μmol/g), was developed from the line C-101 (116 μmol/g) following mutagenesis. The objective of this research was to study the inheritance of very high seed glucosinolate content. Plants of N2-6215 were reciprocally crossed with plants of the line C-101. The F 1 , F 2 , and BC 1 F 1 plant generations were evaluated in two environments and seeds from individual plants were analysed for total glucosinolate content. The very high glucosinolate content in N2-6215 seeds was largely subject to maternal control. No cytoplasmic effects were detected. The trait was found to be oligogenic and determined by at least two or three genes. The estimates of broad-sense heritability were 0.45 and 0.58 in both environments, whereas the estimates of narrow-sense heritability were 0.35 and 0.50. The moderate heritability and oligogenic control of the trait suggest the feasibility of breeding for increased seed glucosinolate content in Ethiopian mustard.

The high stearic acid sunflower mutant CAS-3 is characterized by a low seed oil content, which might represent a constraint for the commercial production of high stearic acid sunflower oil. The objective of the present research was to investigate the relationships between fatty acid profile and seed oil content in CAS-3. Plants of CAS-3 were reciprocally crossed with plants of breeding line ADV-37, with high oil content and standard fatty acid profile. Oil content and fatty acid composition were measured in individual F 2 seeds and F 2 plants (F 3 seeds averaged). Both F 2 seeds and F 2 plants from the cross ADV-37 x CAS-3 had a significantly higher oil content than those from the reciprocal cross, which indicated the existence of cytoplasmic effects in the genetic control of the trait. A consistent negative correlation between oil content and palmitic acid and a positive correlation between oil content and oleic acid were detected both in F 2 seeds and F 2 plants. Conversely, no consistent correlation between oil content and stearic acid was observed, which suggested the feasibility of simultaneous selection for both traits.

Genetic resistance to broomrape (Orobanche cumana Wallr.) race F in sunflower line Jl, derived from the wild perennial species Helianthus grosseserratus Martens and Helianthus divaricatus L., has been reported to be controlled by dominant alleles at a single locus, Or6. However, deviations from this monogenic inheritance have been observed. The objective of the present study was to gain insight into the inheritance of resistance to broomrape race F in the sunflower line Jl. F 1 , F 2 , F 3 and BC generations from crosses between Jl and three susceptible lines, P21, NR5 and HA821 were evaluated. F 1 hybrids showed both resistant (R) and moderately resistant (MR) plants, the latter having a maximum of five broomrape stalks per plant compared with > 10 in the susceptible parents. This indicated incomplete dominance of the Or6 alleles. F 2 plants were classified as R, MR or susceptible (more than five broomrape stalks per plant). Three different segregation ratios were observed: 3:1, 13:3 and 15:1 (R + MR: S), suggesting the presence of a second gene, Or7, whose expression was influenced by the environment. A digenic model was confirmed, based on the evaluation of F 2:3 families.

Safflower (Carthamus tinctorius L.) seeds have a tocopherol fraction dominated by α-tocopherol, which accounts for more than 95% of the tocopherols. α-Tocopherol exerts a high vitamin E activity, but a low in vitro antioxidant action. For non-food applications, replacement of high α-tocopherol by γ-tocopherol is preferred. Because of the limited variability found in germplasm of cultivated safflower, the objective of the present research was to search for variability for tocopherol profile in germplasm of wild safflower species. Bulk seed samples of 77 accessions from six species were analysed for total tocopherol content and profile. One accession of C. oxyacanthus showed increased γ-tocopherol content (36%). Single-seed analysis showed the existence of a bimodal distribution, which included high α-tocopherol (>90%) and high γ-tocopherol (HGT) seeds (>85%). Plants from the HGT seeds bred true for the trait and showed introgression of cultivated safflower, which allowed a rapid selection for cultivated safflower traits. Genetic analysis revealed that the HGT trail was controlled by partially recessive alleles at a single locus Tph1, which will facilitate the transference of the novel trait to diverse safflower germplasms.

Zero erucic acid germplasm of Ethiopian mustard is characterized by high levels of linolenic acid (about 21%). Two genetic sources of low linolenic acid (N2-4961 and HF-186, about 5%), have been developed in a high erucic acid background. The objectives of this research were to study the genetic relationship between the two low linolenic acid lines and to transfer the trait to zero erucic acid germplasm. F 1 seed generations from crosses between both lines had higher average linolenic acid concentration than both parents. F 2 seeds segregated for linolenic acid content following a continuous variation from 1.8 to 7.4%, exceeding the limits of the parental distribution ranges. Transgressive recombinants with very low linolenic acid concentration (0.7-2.7%) were confirmed in the F 3 seed generation. The results suggested that N2-4961 and HF-186 possess alleles for low linolenic acid at different loci. Transgressive low linolenic acid F 3 plants were crossed with plants of a zero erucic acid line and a selection for zero erucic, low linolenic acid was conducted. As a result, a zero erucic acid F 3,4 line containing 1.5 ± 0.7% linolenic acid was developed.

CAS-12 is a sunflower mutant with increased levels of palmitic (C16: 0 = 30%) and oleic (C18: 1 = 55%) acids in its seed oil, hence it has a reduced linoleic acid content (C18: 2 < 5%). This study was conducted to determine the inheritance of high C16: 0 content and its relationship with high C18: 1 content in CAS-12. Reciprocal crosses involving CAS-12, CAS-5 (high C16: 0 content), HAOL-9 (high C18: 1 content) and HA-89 (standard fatty acid profile) were made. The F 1 , F 2 and BC 1 F 1 generations were obtained. The genetic control of the high C16: 0 trait in CAS-12 was partially recessive and gametophytic. In all cases, this character segregated in the ratio 19: 38: 7 (low: intermediate: high C16: 0 content) in the F 2 generation. These results, together with the lack of segregation for C16: 0 content in crosses between CAS-12 and CAS-5, indicated that the genetic control of the high C16: 0 trait in CAS-12 was similar to that in CAS-5 in being controlled by partially recessive alleles (pl, p2, and p3) at three loci. Crosses between HA-89 and CAS-12, and HAOL-9 and CAS-5 (segregating for C16: 0 and C18: 1) demonstrated that the high C16: 0 and the high C18: 1 traits were independently inherited. However, C18: 1 segregation in these crosses exhibited reversal of dominance. Apparently, the low C18: 1 parental lines carried modifier genes causing the deviation.

Safflower (Carthamus tinctorius L.) possesses the highest amount of linoleic acid among the 10 major vegetable oil crops of the world. Very high linoleic acid content is controlled by recessive alleles at a single locus Li. However, deviated segregations from the expected monogenic inheritance have been observed in crosses involving nuclear male-sterile (NMS) lines. The present research was undertaken to study the inheritance of very high linoleic acid content in safflower and its relationship with nuclear male sterility. F 1 , F 2 , F 3 , BC 1 F 1 and BC 1 F 2 seed generations were evaluated in a cross between CR-142 (a line with very high linoleic acid content, 88%) and CL1 (an NMS line with wild-type linoleic acid content, 74%). The genetics of linoleic acid content in male-sterile plants was determined by testcrossing with CR-142. The results confirmed monogenic inheritance. The analysis of the F 3 and BC 1 F 2 to CL1 seed generations demonstrated a repulsion-phase linkage between Li and Ms loci, the latter conferring the NMS trait. The recombination rate between Li and Ms was estimated to be 0.09.

alpha-Tocopherol is the main tocopherol in sunflower seeds (> 90%). Because it exerts a weak antioxidant action in vitro, its partial replacement by other tocopherols is an important breeding objective in this crop. The objective of this research was to develop novel tocopherol profiles in sunflower through mutagenesis and genetic recombination. Seeds of four 'Peredovik' accessions were used for chemical mutagenesis with ethyl methane sulfonate (EMS). Single-seed screening in the M2 generation resulted in two M2 seeds, derived from different M1 plants, with increased gamma-tocopherol contents of 19.2% and 96.7%, respectively. M3 progeny from the M2 seed with the 96.7% content bred true for high gamma-tocopherol content, containing more than 90% gamma-tocopherol. M3 progeny from the M2 seed with only 19.2% gamma-tocopherol segregated in a range from 0 to 84.6%. Selection for high gamma-tocopherol content produced an M(4 : 5) line, designated IAST-1, with a stable high concentration of gamma-tocopherol. Crosses between IAST-1 and T589, with an increased beta-tocopherol content, produced F2 segregants with transgressive levels of up to 77% beta-tocopherol or up to 68% delta-tocopherol. Both novel tocopherol profiles were confirmed in the F3 generation.

The objective of the present research was to study the inheritance of reduced plant height in the sunflower line Dw 89. Plants of the cytoplasmic male sterile version of this line, cmsDw 89 (mean plant height of 47.4 cm) were crossed with plants of the restorer line RHA 271 (mean of 120.9 cm). F 1 plants averaged 120.4 cm, which indicated dominance of standard over reduced plant height. F 2 plants followed a segregation pattern of 1 : 15 (reduced : normal height), suggesting that reduced plant height in Dw 89 is controlled by alleles at two loci, designated Dw1 and Dw2. Class assignment in the F 2 was confirmed through the evaluation of the F 3 generation. Backcrosses to Dw 89 segregated with 1 : 3 (reduced : normal height) ratios, which confirmed the digenic inheritance of the trait. The evaluation of plant height distributions in F 3 families suggested possible genetic interaction between the Dw1 and Dw2 loci.

The zero erucic acid Ethiopian mustard lines developed so far are characterized by an exceptionally high linolenic acid content in the seed oil. The mutant line N2-4961, expressing low linolenic acid content in a high erucic acid background, was developed through chemical mutagenesis. The objective of this research was to study the inheritance of low linolenic acid content in this mutant. Line N2-4961 was reciprocally crossed with its parent line C-101 and the linolenic acid content of the reciprocal F 1 , F 2 and BC 1 generations was studied. No maternal, cytoplasmic or dominance effects were detected in the analysis of F 1 seeds and F 1 plants from reciprocal crosses. Linolenic acid content segregated in 1: 2: 1 ratios in all the F 2 populations studied, suggesting monogenic inheritance. This was confirmed with the analysis of the reciprocal backcross generation. The simple inheritance of low linolenic acid content in N2-4961 will facilitate the transference of this trait to zero erucic acid lines of Ethiopian mustard.

A new race F of broomrape overcomes all known resistance genes in cultivated sunflower, but recently, sources of resistance against race F have been developed. The objective of the present research was to study the inheritance of resistance to race F in crosses between 12 resistant sunflower breeding lines, derived from three different sources of resistance, and the susceptible male-sterile line P-21. Parental lines and F 1 , F 2 , F 3 and BC 1 generations were evaluated for broomrape resistance. Segregations in the F 2 and BC 1 to resistant parent approached resistant to susceptible ratios of 1: 15 and 1: 3, respectively, in most of the crosses, suggesting a double dominant epistasis. However, segregations of 3: 13 and 1: 1 for F 2 and BC 1 , respectively, indicating a dominant-recessive epistasis, were also found. The F 3 data confirmed these results. Owing to the recessive nature of this resistance, it must be incorporated into both parental lines for developing resistant hybrid cultivars.

Racial evolution of sunflower broomrape (Orobanche cernua) has been very rapid in Spain during recent years, in which resistance has been overcome several times and there has been an important increase in areas infested with this parasitic angiosperm. In order to lind resistance to a highly virulent population of sunflower broomrape that could be used directly in breeding programmes, three different sets of cultivated plant material composed of entries were tested by artificial inoculation. All evaluated inbred lines from Morden, Canada, were fully susceptible. Out of the 240 P.I. accessions tested, only 10 segregated for resistance to broomrape, the rest being susceptible. From the 160 USDA breeding lines evaluated, 5% were resistant and 19% segregated for resistance to O. cernua. These lines traced back mainly to crosses of RHA 274 and RHA 801 with Russian, Turkish and Romanian hybrids. The origin of P.I. accessions that segregated for resistance were primarily derived from former USSR and from Romania.

Broomrape (Orobanche cernua Loelf.) is a sunflower parasite which has become a potential threat to this crop in Spam with an increasing incidence in recent last years. In order to investigate the racial situation of the parasite in Spam and to evaluate the resistance of differentials and inbred lines currently used in breeding programmes, two experiments were carried out. In the first, two sets of European sunflower differentials were inoculated with three broomrape populations from different geographical origin. The second experiment studied the reaction to the parasite of 38 inbred lines in comparison with resistant and susceptible checks. Reactions of differential lines resistant to known European broomrape races ranged from complete immunity of lines P-1380-2A and ‘Jdanovski 8281’ to complete susceptibility of ‘Record’ and the universal suscepts. These results confirmed the existence of several physiological races of broomrape in Spain and a different racial composition from that of Eastern Europe. Results from the second experiment showed good resistance of half the restorer lines tested and 36 % of the maintainers and cms lines. This material together with the resistant differential lines constitutes good starting material to be used in developing cultivars resistant to broomrape populations in Spain.

Ethiopian mustard (Brassica carinata Braun) is a potential oil crop in which genes for low erucic acid content of the seed oil have not yet been found. In order to solve this problem the potential of rapeseed (B. napus L.) varieties as a source of these genes has been tested. Reciprocal F1 hybrids between B. carinata and a low erucic acid variety of B. napus, F2, and backcrosses with B. carinata were obtained. The fatty acid composition was determined in half seeds of F1 and segregating generations from reciprocal interspecific crosses. The genetic analysis indicated that the erucic acid content of the seed oil of B. carinata is controlled by two genes with no dominance and additive in action.