[Asymmetric somatic hybridization between mixed wheat and Psathyrostachys juncea]

Area of Science:

• Plant breeding and genetics
• Biotechnology
• Agricultural science

Context:

• Conventional breeding between wheat (Triticum aestivum L.) and Psathyrostachys juncea is hindered by sexual incompatibility.
• Psathyrostachys juncea offers valuable genes for wheat improvement, including resistance to barley yellow dwarf virus, salt, and drought.
• Somatic hybridization presents a viable alternative for creating interspecific hybrids across sexual barriers.

Purpose:

• To establish an efficient somatic hybridization system for wheat and Psathyrostachys juncea using polyethylene glycol (PEG).
• To investigate the influence of ultraviolet (UV) irradiation dosage on protoplast fusion and hybrid regeneration.
• To confirm the hybrid nature of regenerated clones using cytological, biochemical, and molecular markers.

Summary:

• Mixed protoplasts of two wheat cell lines (cha9 and 176) were fused with UV-irradiated Psathyrostachys juncea protoplasts (1 min or 2 min).
• Sixteen clones were generated from the 1-min UV treatment, with five regenerating into green plants confirmed as somatic hybrids.
• The 2-min UV treatment yielded three clones that failed to thrive, indicating UV dosage significantly affects hybrid development and mixed wheat cells enhance regeneration.

Impact:

• Demonstrates the utility of somatic hybridization for transferring desirable traits from wild relatives to wheat.
• Highlights the importance of optimizing fusion parameters, such as UV irradiation, for successful hybrid development.
• Provides a foundation for developing improved wheat varieties with enhanced stress tolerance and disease resistance.