Combining Three Mapping Strategies to Reveal Quantitative Trait Loci and Candidate Genes for Maize Ear Length

Area of Science:

• Plant genetics
• Crop science
• Agricultural research

Background:

• Ear length (EL) in maize (Zea mays L.) is a crucial agronomic trait, positively correlated with grain yield.
• Understanding the genetic control of EL is vital for maize breeding programs aiming to improve crop productivity.

Purpose of the Study:

• To elucidate the genetic architecture of natural variation in maize ear length.
• To identify quantitative trait loci (QTLs) and candidate genes associated with EL.

Main Methods:

• Employed linkage mapping in two distinct populations (F2, four-way cross) across multiple environments.
• Utilized genome-wide association study (GWAS) to pinpoint candidate genes within identified QTL regions.

Main Results:

• Identified a total of 14 QTLs for EL across different populations and environments.
• Discovered three "stable QTLs" consistently detected in common genomic regions.
• Candidate genes associated with the stable QTLs are involved in auxin transport, cell proliferation, and developmental regulation.

Conclusions:

• Maize ear length is a complex trait governed by strong genetic control, influenced by numerous genes with small effects.
• The identified QTLs and candidate genes provide valuable insights into the genetic basis of maize EL and can inform future breeding strategies.