Molecular and morphological insights into the diversity of Moringa oleifera: a comparative analysis

Understanding the genetic diversity of the highly valued multipurpose tree species, drumstick, is crucial for effective breeding and conservation efforts. To evaluate the genetic diversity among 23 drumstick genotypes using both morphological and molecular markers. In a field study, eleven qualitative and twenty-one quantitative morphological traits were evaluated. Additionally, sixty-five genomic microsatellite (SSR) markers were utilized for molecular characterization, among which forty-four demonstrated polymorphism. The morphological study uncovered both qualitative and quantitative differences among the genotypes. Correlation and path analysis identified key traits that influence yield, i.e weight of individual pods and the no. of pods per plant. Genetic divergence analysis based on morphological data grouped the genotypes into six distinct clusters, highlighting significant inter-cluster distances that could be leveraged for heterosis breeding. Molecular marker analysis using the 44 polymorphic SSRs demonstrated substantial genetic diversity, with an average of 5.09 alleles per locus and a mean PIC of 0.57. Observed heterozygosity was relatively low (0.09) compared to expected heterozygosity (0.59), suggesting potential inbreeding or population structure. Phylogenetic analysis based on SSR data using a neighbor-joining tree clustered the 23 genotypes into three main groups, revealing distinct genetic divergence. The combined insights from morphological and molecular analyses provide a comprehensive understanding of the genetic diversity within the studied drumstick germplasm, offering valuable information for targeted breeding strategies and the effective conservation of this important species.