Molecular, morphological and growth studies of three Annona species: a phylogenetic approach

Abstract Molecular and morphological data have greatly enhanced plant systematics. When integrated with phylogenetic analysis, molecular evidence has revolutionized our understanding of plant evolution and prompted major revisions in taxonomic classifications across all levels. This study assessed the morphological, growth indices and molecular diversity among Annona muricata, Annona squamosa , and Annona senegalensis to determine their genetic relationships and systematic classification. Morphological evaluation covered key vegetative and reproductive characters including leaf length (6.5–20 cm), leaf width (2.5–6.5 cm), petiole length (0.5–2.5 cm), fruit diameter (5–20 cm), and seed size (1.0–1.7 cm long). These traits revealed significant interspecific variability, especially in leaf shape, fruit structure, and seed morphology. For molecular analysis, six Random Amplified Polymorphic DNA (RAPD) and nine Simple Sequence Repeat (SSR) markers were employed to evaluate genome variation. Cross-species amplification of all the SSR markers used, successfully amplified in A. muricata and A. squamosa but did not in A. senegalensis . RAPD markers showed cross species-amplification. Polymorphic Information Content (PIC) value ranged from 0.3457 (OPT05) to 0.5926 (OPH04) for RAPD markers with an average of 0.5103 indicating existence of sufficient genetic diversity among the three species studied genotypes. The PIC for SSR markers were uniform (0.5547). Dendrograms constructed from RAPD and SSR data revealed closer genetic affinity between A. muricata and A. squamosa , while A. senegalensis appeared more divergent. The study emphasizes that combining morphological traits with DNA markers is crucial for understanding genetic diversity in Annona species , offering essential insights for their conservation and improvement as underutilized crops.