Transgressive segregation of erucic acid content in Brassica carinata A. Braun

Abstract

Two Ethiopian mustard ( Brassica carinata A. Braun) lines with low (about 10%) and zero erucic acid (C22:1) have been obtained. The low C22:1 mutant line L-2890 was isolated after a chemical-mutagen treatment of C-101 seeds (about 40% C22:1). The zero C22:1 line L-25X-1 was obtained by interspecific crossing. Our objective was to determine the genetic control of low and zero C22:1 contents in these lines and the relationship between the loci controlling these traits. Reciprocal crosses between L-2890, L-25X-1 and high C22:1 lines, and between L-2890 and L-25X-1, were made. The F(1), F(2) and BC(1) F(1) generations were obtained. No maternal or cytoplasmic effects for C22:1 content were observed in any of the crosses. The analysis of the fatty acid composition in the segregating populations from the crosses of L-2890 with the high C22:1 lines C-101 and L-1630 indicated that the segregation patterns fitted a model of two alleles at two loci, M1 and M2, with partial (near complete) dominance for high concentration. The segregation patterns in the cross of the zero C22:1 line L-25X-1 with the high C22:1 line L-1630, were explained on the basis of two genes, E1 and E2, with additive gene action. The F(1) and segregating generations of the crosses L-2890 x L-25X-1 showed a strong transgressive segregation with C22:1 values of up to 50.0%, four-fold higher than those of L-2890. The analyses of the F(2), BC(1)F(1) and F(3) generations indicated that the combination of alleles at four loci, M(1) and M(2) in L-2890 and E(1) and E(2) in L-25X-1, controlled the transgressive segregation for C22:1. The proposed genotypes (C22:1 content) for each parent were as follows: L-2890 (10% C22:1) = m(1) m(1) m(2) m(2) E(1) E(1) E(2) E(2); L-25X-1 (0% C22:1) = M(1) M(1) M(2) M(2) e(1) e(1) e(2) e(2); and C-101 (45% C22:1) = M(1) M(1) M(2) M(2) E(1) E(1) E(2) E(2).

Inheritance of high oleic acid content in the seed oil of mutant Ethiopian mustard lines and its relationship with erucic acid content

“…In the six F 2 populations analysed, three from each reciprocal cross, the distribution of C22:1 content fitted a ratio of 1:15 (χ 2 =0·41, P =0·52) for the low:intermediate-high classes, respectively (Table 4). This segregation suggests the presence of two independent loci, which is in agreement with the model proposed ( M1 and M2 loci) for the inheritance of C22:1 in the mutant L-2890 (Del Río et al 2003).…”

“…The fatty acid composition of the seed oil of mutant line L-2890, standard line C-101, and their reciprocal F 1 s, all grown in the same environment, is presented in Table 1. The inheritance of low C22:1 content in the mutant L-2890 was reported in a previous study and it was concluded that this trait was controlled by two loci ( M1 and M2 ) with partially recessive alleles m 1 and m 2 (Del Río et al 2003; Del Río-Celestino et al . 2005).…”

“…The use of mutagenesis permitted the development of Ethiopian mustard lines with specific fatty acid profiles, such as lines with a high C18:1 content (L-482 with >200 g/kg; Velasco et al 1997), with a low C18:1 content (L-1806 with <110 g/kg; Velasco et al 1997), and lines with low and high C22:1 contents whose genetics have been reported in previous studies (Del Río et al 2003) (L-2890 and L-1630 with about 100 and >500 g/kg, respectively; Velasco et al . 1997, 1998; De Haro et al 2001).…”

“…In B. carinata , Del Río et al (2003) and Del Río-Celestino et al (2005) reported digenic control of C22:1 content in the low-C22:1 mutant L-2890, the high-C22:1 mutant L-1630 and the line zero-C22:1 L-25X-1. The C22:1 content in L-2890 is controlled by partially recessive alleles ( m 1 and m 2 ) at two loci M1 and M2 , in L-1630 is controlled by alleles ( E 1 and E 2 ) with additive effects at the loci E1 and E2 , while line L-25X-1 was controlled by alleles ( e 1 and e 2 ) acting in an additive and equal manner at two loci E1 and E2 .…”

Determination of Essential Fatty Acid Composition among Mutant Lines of Canola (Brassica napus), through High Pressure Liquid Chromatography

“…To achieve this, induced mutations and hybridization can play a vital role. The use of mutagenesis permitted the development of Ethiopian mustard lines with specific fatty acid profiles such as lines with a high oleic acid content and some lines with a low C18:1 content (Velasco et al 1997) and also lines with low and high C22:1 contents whose genetics have been reported in previous studies (Velasco et al 1997, 1998; De Haro et al 2001; Del Rio et al 2003;). These oils with specific fatty acid profiles are in demand because of their improved nutritional and/or technological properties (Kinney 1994).…”