Fuente: PubMed "rice" iScience. 2026 Mar 26;29(4):115487. doi: 10.1016/j.isci.2026.115487. eCollection 2026 Apr 17.ABSTRACTThis study employed high-throughput sequencing to assemble and annotate the complete chloroplast genomes of three Sagittaria species. These genomes showed a conserved quadripartite structure, with length (∼178,339 bp) and GC content (36.8%-36.9%) exceeding those of other Alismataceae genera. Comparative analysis revealed structural conservation but species-specific variations at the JLB and JSA junctions. We identified numerous SNPs and SSRs across five species and found the rps16 gene and trnT-trnL spacer to be hypervariable, suggesting them as molecular markers. Codon usage bias indicated limited mutational pressure. Selective pressure analysis detected positive selection in clpP and ycf2. Phylogenetic analysis strongly supported Caldesia as sister to Sagittaria and placed S. platyphylla basally. Divergence time estimation suggested that Sagittaria and Caldesia split approximately 23.53 million years ago (Mya), while the internal diversification of Sagittaria occurred around 4.82 Mya. Our findings provide invaluable genomic resources and deep insights into the evolution, systematics, and potential genetic improvement of Sagittaria, which has significant ecological and industrial applications.PMID:42006308 | PMC:PMC13091477 | DOI:10.1016/j.isci.2026.115487