Zinc Finger Protein 30 Is a Novel Candidate Gene for Kernel Row Number in Maize

Area of Science:

• Plant genetics
• Maize breeding
• Genomics

Background:

• Kernel row number (KRN) is a critical trait for maize yield, but its genetic underpinnings are not well understood.
• Understanding the genetic basis of KRN is essential for developing high-yielding maize varieties.

Purpose of the Study:

• To identify candidate genes regulating KRN in maize.
• To map quantitative trait loci (QTLs) associated with KRN.
• To explore the genetic mechanisms controlling ear development in maize.

Main Methods:

• Development of 318 BC4F4 chromosomal segment substitution lines (CSSLs) using Baimaya (BMY) as donor and B73 as recurrent parent.
• Construction of a high-density genetic map with 2859 SNP markers for QTL analysis.
• Integration of linkage mapping and transcriptome analysis of immature ears from near-isogenic lines (NILs).

Main Results:

• Nineteen QTLs controlling KRN were detected across three environments and BLUP values, with one major-effect QTL (qKRN4.09-1) consistently identified.
• A candidate gene, Zm00001eb205550, was uncovered and showed significant downregulation in the BMY allele of qKRN4.09-1.
• Two missense variants were identified in Zm00001eb205550 between BMY and B73 alleles, and this gene was preferentially expressed in developing ears.
• Pyramiding favorable alleles from five stable QTLs significantly increased KRN in maize.

Conclusions:

• Zm00001eb205550 is a strong candidate gene for regulating KRN in maize.
• The study provides valuable genetic targets for enhancing KRN and improving maize yield through breeding.
• Findings contribute to a deeper understanding of the genetic control of maize ear development.