Molecular characterization of genetic diversity and mycorrhizal responsiveness in maize (Zea mays) cultivars using 18s rRNA, RBCL and ISSR markers

Abstract

Amal Y. Aldhebiani*, Amal T. K. Ashour, Neveen S. Geweely, Mohamed Abu-Zeid, Givin J. Hosburgh, Duncan D. Cameron and Salah E. M. Abo-Aba

Maize (Zea mays) is a globally significant crop, and its genetic diversity is crucial for its adaptation and improvement through breeding programs. This study employed molecular markers 18S rRNA, RBCL gene sequences, and Inter-Simple Sequence Repeats (ISSR) to assess the genetic diversity and mycorrhizal responsiveness of 18 maize cultivars cultivated in Saudi Arabia. Phylogenetic analysis using maximum likelihood methods revealed two major clades, with significant variation in mycorrhizal responsiveness among genetically similar cultivars. The results indicate that while genetic relatedness is a factor, it is not a strong predictor of mycorrhizal symbiosis. ISSR markers were particularly effective in revealing polymorphisms, with the cultivars displaying considerable genetic diversity, thus supporting their use in future marker-assisted selection and breeding programs. These findings provide valuable insights into the genetic structure of maize cultivars in Saudi Arabia and offer a foundation for enhancing crop traits, such as nutrient uptake and stress tolerance, particularly in arid environments. This study underscores the importance of molecular markers in elucidating phylogenetic relationships and advancing genetic improvement strategies in maize.