Asymmetric somatic hybridization between wheat (Triticum aestivum) and Avena sativa L.

Protoplasts from cell suspensions of young-embryo-derived calli, which were non- regenerable for long-term subculture and protoplasts from embryogenic calli with the regeneration capacity of 75% of the same wheat Jinan 177, were mixed as recipient. Protoplasts from embryo-genic calli of Avena sativa (with the regeneration capacity of less than 10%) irradiated with UV at an intensity of 300 mW/cm2 for 30 s, 1 min, 2 min, 3 min, 5 min were used as the donor. Proto-plasts of the recipient and the donor were fused by PEG method. Many calli and normal green plants were regenerated at high frequency, and were verified as somatic hybrids by chromosome counting, isozyme, 5S rDNA spacer sequence analysis and GISH (genomic in situ hybridization). Fusion combination between protoplasts either from the cell suspensions or from the calli and UV-treated Avena sativa protoplasts could not regenerate green plants.