The Effect of Chromosome Arm 1BS on the Fertility of Alloplasmic Recombinant Lines in Bread Wheat with the Hordeum vulgare Cytoplasm

Abstract

The genetic mechanisms of fertility restoration in alloplasmic bread wheat with the barley cytoplasm are poorly explored. The effect of the 1BS chromosome arm on the fertility of bread wheat with the H. vulgare cytoplasm was studied depending on the incompleteness/completeness of the cytonuclear compatibility. (i) Three self-fertile (SF) lines and one partially fertile (PF) line with an incomplete cytonuclear compatibility and (ii) four self-fertile (SF) lines with a complete cytonuclear compatibility were studied. For the lines in group (i), the heteroplasmy (simultaneous presence of barley and wheat copies) of the 18S/5S mitochondrial (mt) repeat was revealed as well as the barley-type homoplasmy of chloroplast simple sequence repeats (cpSSRs). In the lines in group (ii), the 18S/5S mt repeat and cpSSRs were found in the wheat-type homoplasmic state. In all of the lines, the 1BS chromosome arm was substituted for the 1RS arm. The F₁ plants of SF(i)-1BS × 1RS hybrids were fertile. The results of a segregation analysis in the F₂ plants of SF(i)-1BS × 1RS showed that 1BS carries a single dominant fertility restorer gene (Rf) of bread wheat with the H. vulgare cytoplasm. All of the F₁ plants of PF(i)-1BS × 1RS hybrids were sterile. A single dose of this restorer gene is not sufficient to restore fertility in this alloplasmic PF(i) line. All of the F₁ and F₂ plants of SF(ii)-1BS × 1RS hybrids were self-fertile.

Keywords: 1BS chromosome arm; alloplasmic lines (H. vulgare)-T. aestivum; cytonuclear compatibility; mitochondrial and chloroplast DNA.

Figure 1

The scheme for the production of alloplasmic recombinant (H. vulgare)-T. aestivum lines L-15(1), L-15(2), L-23(1), L-23(2). (L-319: barley line; varieties of bread wheat: Sar29: Saratovskaya 29; Mir808: Mironovskaya 808; Pyr28: Pyrotrix 28; Sar210: Saratovskaya 210; Nov67: Novosibirskaya 67).

Figure 2

The scheme for the production of alloplasmic recombinant lines (H. vulgare)-T. aestivum lines L-55(1), L-55(2), L-55(3) and L-55(4). (Nep: barley variety Nepolegaushii; varieties of bread wheat: Sar29: Saratovskaya 29; Mir808: Mironovskaya 808; Pyr28: Pyrotrix 28.

Figure 3

Agarose gel electrophoresis of PCR products from alloplasmic lines using the 18S/5S mt repeat. M: 100 bp ladder marker; 1: L-319; 2: Om29; 3: Sar29; 4: L-15(1); 5: L-15(2); 6: L-23(1); 7: L-23(2); 8: L-55(1); 9: L-55(2); 10: L-55(3); 11: L-55(4); 12: L-17(3); 13: L-17(3)/Om29; 14: Om29/L-17(3).

Figure 4

Amplified SSR markers TaCM4 and TaCM9 separated in 2% agarose gel electrophoresis. 1: L-15(2); 2: L-15(1); 3: L-17; 4: L-17(3)/Om29; 5: Om29/L-17(3); 6: L-55(2); 7: L-55(1); 8: L-55(4); 9: L-55(3); 10: wheat variety Omskaya 29; 11: L-23(2); 12: L-23(1); 13: barley L-319; 14: wheat variety Saratovskaya 29; 15: negative control (distilled water); M: GeneRuler 100 bp DNA Ladder.

Figure 5

Multiplex PCR detection of 1BL.1RS translocation with a codominant marker. M: 100 bp ladder marker. 1: Om29-1RS.1BL; 2: Sar29; 3: F₁ of L-15(1) × Om29-1RS.1BL; 4: F₂ of L-15(1) × Om29-1RS.1BL; 5: F₂ of L-15 (1) × Om 29-1RS.1BL (homozygous for the 1RS.1BL); 6: F₂ of L-15 (1) × Om 29-1RS.1BL; 7: F₂ of L-23(1) × Om 29-1RS.1BL; 8: F₂ of L-55(1) × Om 29-1RS.1BL; 9: F₂ of L-55(3) × Om 29-1RS.1BL (heterozygotes for 1RS.1BL).