High-density genetic map construction and QTL analysis of the first flower node in kenaf using RAD-seq

Area of Science:

• Plant genetics
• Agricultural science
• Natural fiber crops

Background:

• The first flower node in kenaf (Hibiscus cannabinus L.) is crucial for fiber yield.
• Genetic mechanisms regulating this trait are not well understood.

Purpose of the Study:

• To construct a high-density genetic linkage map for kenaf.
• To identify genetic loci and candidate genes associated with the first flower node trait.

Main Methods:

• Restriction-site associated DNA sequencing (RAD-seq) was used to generate a genetic map.
• Quantitative trait loci (QTL) analysis was performed on 148 hybrid kenaf progeny.
• Gene annotation and RT-qPCR were utilized to identify candidate genes.

Main Results:

• A high-density genetic map with 3418 bin markers across 18 linkage groups was created.
• Two significant QTLs, FFN6.1 and FFN6.2, were identified on LG6, linked to the first flower node.
• 373 candidate genes were predicted, and three were validated using RT-qPCR.

Conclusions:

• This study provides a foundational understanding of the molecular basis for the first flower node trait in kenaf.
• The identified QTLs and candidate genes offer targets for future genetic improvement of kenaf fiber yield.