TeoNAM: A Nested Association Mapping Population for Domestication and Agronomic Trait Analysis in Maize

Area of Science:

• Plant genetics
• Genomics
• Agronomy

Background:

• Recombinant inbred lines (RILs) are crucial for mapping complex trait genes.
• Existing maize RIL populations lack diverse teosinte parental lines.

Purpose of the Study:

• Develop a novel maize RIL population using multiple teosinte inbred lines.
• Utilize this population for quantitative trait loci (QTL) mapping and discovering teosinte allelic variation.

Main Methods:

• Created a teosinte nested association mapping (TeoNAM) population from five teosinte inbreds and maize inbred W22.
• Genotyped 1257 BC1S4 RILs using 51,544 SNPs, constructing a high-density genetic map (1540 cM).
• Performed joint linkage mapping (JLM) and genome-wide association study (GWAS) for 22 traits.

Main Results:

• Identified 255 QTL via JLM, with many near known or novel candidate genes.
• Reported PROSTRATE GROWTH1 as a QTL for tillering in teosinte and maize.
• Detected QTL for flowering time and other traits where teosinte alleles confer maize-like phenotypes.

Conclusions:

• The TeoNAM population is a valuable resource for QTL mapping and identifying novel teosinte variation.
• Teosinte alleles can contribute desirable maize-like traits, offering potential for crop improvement.
• This study highlights the genetic insights gained from inter-species RIL populations.