Assessment of genetic diversity and trait correlation among spine gourd ( <i>Momordica dioica</i> robx.) landraces for genetic improvement

The present study assessed the genotypic and phenotypic diversity and key trait correlations among 17 landraces of Momordica dioica Roxb. and one check genotype to identify promising genotypes for future genetic enhancement. Traits exhibited high genotypic (99.53 %) and phenotypic (97.69 %) coefficients of variation indicating substantial variability with minimal environmental influence. Correlation and path analyses identified fruit yield per plant as strongly influenced by traits such as vine length, internodal length, fruit size, and single fruit weight. Multivariate cluster analysis grouped the genotypes into four distinct clusters, with one cluster (cluster IV) harbouring the largest number of genotypes (n=11) and exhibiting superior mean performance for traits. Molecular diversity analysis using ISSR markers revealed a moderate level of genetic variation among the landraces, with similarity coefficients ranging from approximately 0.75 to 1.00. The ISSR primers generated polymorphic bands, and the observed polymorphic information content (PIC) values indicated moderate to good marker informativeness, confirming the suitability of ISSR markers for diversity analysis in spine gourd. The UPGMA dendrogram based on ISSR data grouped the landraces into distinct clusters, identifying several accessions that were genetically distant from the main groups. These genetically divergent genotypes may be used for hybridization and recombination breeding.