Microsatellite diversity in four cultivated species of Actinidiaceae and Rutaceae

Abstract

Microsatellites or Simple Sequence Repeats (SSRs) are short iterations of 1-6 bp in the genomes of almost all living organisms. Our study aimed to explore the microsatellite diversity in four cultivated species, namely Actinidia chinensis, Actinidia eriantha, Citrus maxima, and Citrus sinensis of the Actinidiaceae and Rutaceae families. We present a comprehensive analysis of microsatellite abundance, distribution, and motif composition in the genomes of these species. The association of microsatellite abundance with genomic features such as genome size, GC content, number of microsatellites, relative abundance, and relative density was also examined. The results revealed significant variations in the frequency and distribution of microsatellites across the genomes of these four species. Notably, a positive correlation was observed between genome size and microsatellite number as well as with GC content, indicating that larger genomes provide more opportunities for the accumulation of microsatellites. Furthermore, a negative correlation of genome size with relative microsatellite abundance and relative density was observed. These findings provide new insights into the microsatellite landscape of Actinidiaceae and Rutaceae, which could be explored for the development of microsatellite markers for diverse applications in the characterization of genetic diversity, molecular plant breeding, and phylogenetic analysis.