Gene introgression from common wheat into Aegilops L

Area of Science:

• Plant Genetics and Breeding
• Crop Science
• Evolutionary Biology

Background:

• Understanding gene flow between wild relatives and cultivated crops is crucial for breeding programs and conservation.
• Common wheat (Triticum aestivum) possesses valuable traits that could enhance its wild relatives, such as Aegilops species.

Purpose of the Study:

• To assess the feasibility of gene introgression from common wheat into four Aegilops species.
• To evaluate crossability, hybrid embryo development, and fertility in interspecific crosses.

Main Methods:

• Artificial indoor crosses were performed using seven genotypes of four Aegilops species as female parents and common wheat as the male parent.
• Cross rates, callus initiation, germination of hybrid embryos, and seed-set rates in back-crosses and selfing were analyzed.

Main Results:

• Crossability varied significantly among Aegilops species, with Aegilops tauschii showing the highest rate (up to 46.49%) and Aegilops speltoides the lowest (0.19%).
• Hybrid embryos from Aegilops ovata and Aegilops tauschii exhibited higher callus initiation and germination rates compared to Aegilops cylindrica and Aegilops speltoides.
• Interspecific hybrids demonstrated very low fertility, with seed-set rates ranging from 0% to 4.36% in back-crosses and selfing.

Conclusions:

• The probability of natural gene introgression from Triticum aestivum into Aegilops species is extremely low due to poor crossability and fertility of hybrids.
• Despite low success rates, specific Aegilops species show potential for limited gene transfer under controlled conditions.