Abstract

The identification of quantitative trait loci (QTLs) for root traits can provide useful indications on their genetic basis and the associated effects on grain yield under different water regimes. Furthermore, the availability of molecular markers linked to QTLs controlling variation for root traits and grain yield will allow for the implementation of marker-assisted selection to improve productivity. In maize (Zea mays L.), four mapping populations have been investigated to locate QTLs for root traits under controlled conditions and/or in the field. A comparative analysis of the QTL results was carried out based on the availability of molecular markers common to the investigated populations and the UMC maize reference map. Several chromosome regions affected root traits in two or even three populations. A number of these regions also affected grain yield under well-watered and/or drought-stressed conditions. The most important QTL effects were detected on chromosome bins 1.03, 1.06, 1.08, 2.03, 2.04, 7.02, 8.06 and 10.04. Exploiting the syntenic information available for maize and rice, a number of QTLs for root traits described in rice were found to map in regions syntenic to a number of the listed maize chromosome bins (e.g., bin 2.04). The development of near isogenic lines (NILs) for the most important QTLs will allow to investigate whether the concomitant effects of the QTLs on root traits and grain yield are due to linkage and/or pleiotropy and, ultimately, may offer the opportunity to clone the genes underlying such QTLs. Although QTL analysis remains a resource-demanding undertaking, its integration with genomics and post-genomics approaches will play an increasingly important role for the identification of genes affecting root characteristics and grain yield in maize and for harnessing the favourable allelic variation at such loci.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.