Grain Size Selection Using Novel Functional Markers Targeting 14 Genes in Rice

Area of Science:

• Plant Genetics
• Agricultural Science
• Molecular Breeding

Background:

• Grain size is a critical trait in rice breeding, influencing both yield and quality.
• Understanding and manipulating genes controlling grain size is essential for developing superior rice varieties.

Purpose of the Study:

• To develop robust and efficient functional markers for 14 key rice grain size genes.
• To genotype variations in these genes across diverse rice cultivars and assess their impact on grain size traits.

Main Methods:

• Developed 21 PCR-gel-based markers targeting functional nucleotide polymorphisms (FNPs) in 14 grain size genes.
• Genotyped 257 rice accessions from the Rice Diversity Panel 1 for allele mining.
• Investigated trait contributions of FNPs and conducted quantitative trait loci (QTL) analysis.

Main Results:

• All developed markers effectively genotyped allele types.
• Identified rare alleles for GW2, GS2, and GL3.1 associated with larger grains.
• Demonstrated significant trait contributions for most FNPs, particularly GS3, GW5, and GL7, with GW5 identified as a major regulator of grain size.

Conclusions:

• The developed functional markers are reliable for genotyping diverse rice cultivars.
• These markers can facilitate targeted breeding strategies to optimize grain size for improved yield and quality.