In Vivo Rice Haploid-Induction System by an Egg Cell-Specific Peptidase Knockout

Area of Science:

• Plant breeding
• Genetics
• Molecular biology

Background:

• Doubled haploid (DH) technology accelerates crop improvement and genetic studies.
• In vitro anther culture is the primary method for rice haploid production.
• Genotype dependency limits the efficiency of anther culture in many rice varieties.

Purpose of the Study:

• To describe a novel protocol for in vivo haploid induction in rice.
• To overcome genotype-specific limitations of current haploid induction methods.
• To establish a convenient and efficient system for producing rice doubled haploid lines.

Main Methods:

• Utilizing CRISPR-Cas9 to create knockout mutations in the egg cell-specific peptidase (ECS) gene.
• Selecting homozygous Osecs mutants for haploid induction experiments.
• Employing flow cytometry to identify haploids in the offspring of Osecs mutants.

Main Results:

• A functional maternal in vivo haploid induction system mediated by ECS knockout was established.
• The developed protocol offers a convenient, time-saving, and labor-saving alternative.
• Successful production of rice doubled haploid lines through this new method.

Conclusions:

• The ECS-mediated maternal in vivo haploid induction system provides an efficient strategy for rice breeding.
• This method significantly reduces the challenges associated with genotype dependence in haploid production.
• The protocol facilitates faster generation of doubled haploid rice lines for research and development.