Jackfruit is an important tropical fruit crop with high nutritional and economic value, but efficient morphological characterization of germplasm remains limited, which impedes varietal identification and breeding efforts. Hence, the present study aimed to assess morphological diversity and develop phenotypic fingerprinting of thirty jackfruit genotypes using twenty-three qualitative traits based on IPGRI descriptors (IPGRI, Rome, Italy). The study was conducted during 2024–2025 at the College of Horticulture, UHS campus, GKVK, Bengaluru, Karnataka, India. Qualitative characterization revealed predominance of spherical crown shape (10 genotypes; 33.33%) with spreading growth habit (13; 43.33%), elliptic dark green leaves with acuminate apex (17; 56.67%) and oblique base (19; 63.34%), and fruits mainly borne on secondary branches (14; 46.66%) with cluster fruiting habit (16; 53.34%). Ellipsoid fruits (19; 63.33%) with depressed stalk attachment (16; 53.34%) and spiny peel surface (29; 96.66%) with sharp spines (22; 73.33%) were dominant, along with light yellow flakes (12; 40.00%) having firm texture (25; 83.33%) and medium thickness (13; 43.34%). Vivipary was absent in most genotypes (22; 73.34%), while ellipsoid seeds (11; 36.67%) with creamish seed coat color (13; 43.34%) were observed. Multiple Correspondence Analysis (MCA) indicated considerable phenotypic variability among genotypes, with the first three dimensions explained 22.43% of the total variation. Heat map clustering grouped the genotypes into three major clusters, with Cluster I (83.33%) and Cluster II (13.33%) were further divided into subclusters, while Cluster III contained a single distinct genotype (BSH), highlighting distinct phenotypic clustering independent of geographic origin. Phenotypic fingerprinting identified unique morphological markers such as irregular crown shape, retuse leaf apex, smooth peel surface and petiole twisting orientation, which can serve as a diagnostic trait for varietal identification. The study offers a strong phenotypic foundation for germplasm characterization, conservation, and selection of elite jackfruit genotypes for future breeding programs.
Gurumurthy et al. (Fri,) studied this question.