Uniqueness of Traditional Rice Cultivars of Kerala Revealed by Diversity Analysis

Farmer-maintained traditional rice landraces represent vital germplasm reservoirs for genetic enhancement programs. These genotypes often harbor adaptive traits conferring tolerance to diverse abiotic and biotic stressors. Comprehensive characterization and evaluation of such genetic resources are imperative for their effective utilization in rice improvement strategies aimed at developing resilient and high-yielding cultivars.

In this present study, seventy traditional rice landraces were assessed and classified using cluster analysis, which enabled the grouping of genotypes into distinct clusters based on their phenotypic and genetic similarities. The evaluated rice genotypes exhibited substantial variability across several agronomic traits, indicating significant potential for utilization in crop improvement programs. Genetic divergence analysis using Mahalanobis’ D² statistics facilitated the categorization of genotypes into distinct clusters. The insights derived from this clustering approach can streamline the breeder’s efforts by reducing the time needed to screen extensive germplasm collections for promising breeding material. Moreover, the identified clusters serve as a valuable resource for selecting suitable donor parents in the development of drought-tolerant rice genotypes.

The seventy rice genotypes were classified into ten distinct clusters, with Cluster I comprising the majority, encompassing 61 genotypes. In contrast, each of the remaining clusters (Clusters II to X) was monogenic, containing a single genotype each. The study revealed nine cultivars namely Kokkan, Njavara Manja, Thekkan, Kadamkudy Kuruka, Karinellu, Nooranvella, Gandhakashala, Oorkayama and Thekkan chitteni formed individual clusters indicating their uniqueness.