Artificial Polyploidization Enhances Morphological, Physiological, and Biological Characteristics in Melothria scabra Naudin

Cucamelon (Meltric scabra Naudin, Cucurbitaceae) is a climbing, herbaceous perennial plant with various culinary and medicinal uses. The current study aimed to develop novel autopolyploid genotypes of M. scabra through in vitro polyploidization and assess their morphological and phytochemical characteristics. For polyploid induction, oryzalin was employed as an antimitotic agent, and it was applied at various concentrations (40, 60, and 80 μM) and durations (24 and 48 h). Flow cytometry analysis confirmed the successful induction of polyploids, with polyploidization efficiency ranging from 2.5% to 15%. From a total of 240 treated plants, a total of 20 autotetraploid plants were obtained. The obtained polyploid and control diploid genotypes were cultivated under greenhouse conditions. Further, the plants were transferred to field conditions, and the leaves, flowers, and fruits were harvested to be evaluated for the morphological, biochemical, and biological activity variations among the obtained genotypes. Morphological comparisons between diploid and autotetraploid plants revealed significant differences in flower characteristics, fruit attributes, and leaf morphology. Nutritional evaluation demonstrated enhancement of key parameters in the induced polyploids compared to the diploid plants, including glucose, fructose, carotenoid, polyphenol, and antioxidant contents, highlighting the potential impact of polyploidization on these traits. The results from this study highlight the potential of artificial chromosome doubling as an effective breeding strategy in M. scabra and related plant species.