Identification of a Major QTL Controlling Maize Lateral Root Branching Number Through Integrated BSA-Seq and...

Area of Science:

• Plant Genetics and Genomics
• Agricultural Science
• Root Biology

Background:

• Maize lateral roots are crucial for anchorage, support, and nutrient/water uptake.
• The genetic basis of maize lateral root development is not fully understood.
• Understanding these mechanisms can improve crop architecture and stress tolerance.

Purpose of the Study:

• To identify genetic loci controlling lateral root development in maize.
• To map quantitative trait loci (QTLs) associated with lateral root branching number (LRN).
• To identify candidate genes underlying LRN variation.

Main Methods:

• An F2 population was created by crossing maize inbred lines with contrasting lateral root phenotypes.
• Quantitative trait loci (QTL) mapping and bulked segregant analysis sequencing (BSA-seq) were employed.
• Transcriptome analysis of brace root samples at different developmental stages was performed.

Main Results:

• Two major QTLs for LRN were identified on chromosomes 7 and 9.
• The QTL on chromosome 9 (qLRN9) showed significant association with LRN and was narrowed to a 1.63 Mb interval.
• Several candidate genes within the qLRN9 interval were identified through integrated QTL and transcriptome analysis.

Conclusions:

• This study successfully mapped QTLs controlling maize lateral root development.
• Identified candidate genes provide targets for future research into root architecture.
• Findings offer valuable genetic resources for enhancing maize root systems, lodging resistance, and drought tolerance.