Linking fruit and stone morphology with germination and polyembryony in two mango genotypes, Olour and Kurukkan

BACKGROUND: Mango (Mangifera indica L.) productivity improvement depends partly on the identification and characterization of suitable polyembryonic genotypes used in propagation. Understanding the relationship between fruit and stone morphology and early reproductive traits such as germination and polyembryony is essential for effective germplasm utilization. The present study aimed to evaluate morphological variability, germination behavior, and polyembryony in two polyembryonic mango genotypes, 'Olour' and 'Kurukkan', grown at the ICAR-Indian Agricultural Research Institute, New Delhi. RESULTS: A total of 260 fruits were analyzed for fruit weight, fruit length, fruit width, stone weight, stone length, and stone width, along with germination percentage, number of seedlings per stone, and polyembryony. Descriptive statistics indicated greater variability in mass-based traits compared to linear dimensions. Linear models revealed strong varietal differences in fruit weight, fruit width, stone weight, and stone width, whereas stone length exhibited relatively weak differentiation between genotypes. Correlation analysis showed strong positive associations among most fruit and stone traits, suggesting coordinated fruit-stone development. Allometric analysis demonstrated consistent sub-isometric scaling relationships, indicating conserved developmental allocation patterns across genotypes. Logistic and Poisson generalized linear models indicated that fruit and stone morphological traits had negligible influence on germination, seedling number per stone, and polyembryony. Deviance-based variance partitioning further revealed that varietal effects explained less than 1% of the variation in these early reproductive traits. CONCLUSIONS: The findings indicate strong developmental canalization of germination and polyembryony in polyembryonic mango genotypes. Despite clear morphological differences between 'Olour' and 'Kurukkan', early reproductive responses remain largely independent of fruit and stone morphology. These results provide important insights for germplasm characterization and support the use of polyembryonic genotypes in propagation-oriented mango improvement programs.