Integrating Association Mapping, Linkage Mapping, Fine Mapping with RNA Seq Conferring Seedling Vigor Improvement for...

Area of Science:

• Plant genetics and breeding
• Genomics
• Agronomy

Background:

• Direct seeded rice (DSR) cultivation is expanding, requiring improved genetic traits for success.
• Enhancing seedling vigor is a primary objective for DSR breeding programs.
• Understanding the genetic basis of seedling vigor in deep-sown DSR is essential.

Purpose of the Study:

• To investigate the genetic control of seedling vigor in deep-sown direct seeded rice.
• To identify candidate genes associated with mesocotyl elongation and germination.
• To develop pre-breeding materials for direct seeded rice.

Main Methods:

• Genome-wide association mapping and linkage mapping were employed.
• Fine mapping and RNA-sequencing were used to identify candidate genes.
• RT-PCR was utilized for validation of potential candidate genes.

Main Results:

• Significant phenotypic variation in seedling vigor was observed.
• Mesocotyl length positively correlated with germination, root, and shoot length.
• Seven potential candidate genes were identified, and four introgression lines with desirable traits were developed.

Conclusions:

• The study provides valuable pre-breeding materials and candidate genes for direct seeded rice improvement.
• Developed introgression lines possess traits beneficial for deep-sown DSR conditions.
• Results support genomics-assisted breeding for enhancing genetic gains in DSR programs.