Alloplasmic wheat - Elymus ciliaris chromosome addition lines

Area of Science:

• Plant genetics
• Cytology
• Crop science

Background:

• Alloplasmic euploid wheat with Elymus ciliaris cytoplasm exhibits male sterility and reduced vigor.
• Fertility and vigor restoration in alloplasmic wheat are crucial for breeding programs.

Purpose of the Study:

• To identify and characterize genes responsible for fertility restoration in alloplasmic wheat.
• To investigate chromosome translocations involving Elymus ciliaris chromosomes in wheat.

Main Methods:

• Development of alloplasmic wheat lines with Elymus ciliaris cytoplasm.
• Identification of specific Elymus ciliaris chromosomes (1Sc, 1Yc) conferring fertility restoration.
• Isolation and characterization of chromosome translocations involving the 1Yc chromosome.

Main Results:

• Alloplasmic plants with E. ciliaris chromosomes 1Sc or 1Yc, carrying gliadin genes Gli-Sc1 and Gli-Ycl, showed restored vigor and fertility.
• The fertility restoring genes on 1Sc and 1Yc were designated Rf-Sc1 and Rf-Yc1, respectively.
• Two chromosome translocations involving the 1Yc chromosome were identified, one with wheat chromosome 3B and another with an E. ciliaris chromosome (L).
• A specific line with a 1Yc translocation, E. ciliaris chromosome A, and lacking wheat 6A, exhibited resistance to Puccinia recondita.

Conclusions:

• The Elymus ciliaris chromosomes 1Sc and 1Yc carry essential Rf genes for restoring fertility in alloplasmic wheat.
• Chromosome translocations can be utilized to introgress desirable traits, such as disease resistance, from E. ciliaris into wheat.
• Further investigation into the relationship between fertility restoration and nucleolar organizing regions is warranted.