Screening and Validation of Leaf Width-Related Genes in Inbred Maize Lines

Area of Science:

• Plant genetics and genomics
• Agricultural science
• Maize breeding

Background:

• Leaf width is crucial for maize (Zea mays) planting density and photosynthetic efficiency.
• Understanding the genetic basis of leaf width is essential for crop improvement.

Purpose of the Study:

• To identify genes regulating maize leaf width using a genome-wide association study (GWAS).
• To investigate the role of candidate genes in leaf width determination.

Main Methods:

• Conducted a GWAS on 80 inbred maize lines using 1.49 × 10^6 single nucleotide polymorphisms (SNPs).
• Analyzed phenotypic leaf width data over two years.
• Performed quantitative PCR (qPCR) to analyze gene expression.
• Assessed EMS mutant lines for mutations in candidate genes.

Main Results:

• Identified 14 significant SNPs associated with leaf width on chromosomes 1, 2, 3, 5, 6, 7, 8, and 9 (p < 0.000001).
• Located five candidate genes within 9.7 kb of significant SNPs, including Zm00001d044327.
• Found significant differences in Zm00001d044327 expression in lines with varying leaf widths.
• Mutant lines with mutations in Zm00001d044327 exhibited narrow leaf width.

Conclusions:

• Zm00001d044327 is a key regulator of maize leaf width.
• This finding has implications for optimizing maize planting density and photosynthetic efficiency through genetic selection.