An efficient rice mutagenesis system based on suspension-cultured cells

Area of Science:

• Plant genetics
• Crop science
• Molecular biology

Background:

• Plant mutants are crucial resources for crop improvement and understanding gene function.
• Traditional seed mutagenesis methods are often inefficient for generating diverse mutant libraries.

Purpose of the Study:

• To develop a highly efficient ethyl methanesulfonate (EMS) mutagenesis system using suspension-cultured rice cells.
• To generate a mutant library for crop breeding and gene functional studies.

Main Methods:

• Treatment of rice (Oryza sativa L.) suspension-cultured cell clusters with 0.4% EMS for 18-22 hours.
• Regeneration of treated cells into whole plants to establish mutant lines.
• Phenotypic evaluation and genetic analysis of generated mutants.

Main Results:

• Achieved 29.4% independent mutant lines with visible phenotypic variations.
• Observed mutations in important agronomic traits like grain size, panicle architecture, heading date, and disease sensitivity.
• Identified a novel allelic mutant of the EUI gene affecting uppermost internode length.

Conclusions:

• The developed EMS mutagenesis system based on cell cultures is highly efficient for generating diverse rice mutants.
• This system facilitates crop breeding and gene functional studies by providing a rich source of genetic variations.
• The identified EUI mutant demonstrates the system's capability to uncover new allelic variations in important genes.