Ex Situ Conservation and Genetic Diversity Assessment in the Iluko Indigenous Dioscorea "Buga"

Abstract

The wild Dioscorea “buga” is an indigenous Iluko root crop with significant potential as a food source. Despite being recognized as a food plant, limited information exists about its botany, ecology, ethnobotany, utilization, and conservation. This study documented these aspects in selected sites across Ilocos Norte, Ilocos Sur, Abra, and Cagayan. Germplasm materials were assembled and conserved in a field genebank at MMSU, Batac City. To enhance cost-effective germplasm management for ex situ conservation, morphological characterization and genetic diversity estimation were conducted using the Shannon-Weaver diversity index and NTSYS-pc. Results revealed distinct features of the “buga” plant, such as spiny anchor roots, large underground tubers, and long stolons suspending the tubers. The plant demonstrated adaptive mechanisms for survival in wild conditions. Linguistic and ethnobotanical evidence suggests its longstanding use as part of rural diets in the Ilocos Region, although its utilization has decreased over time. Conservation efforts for this crop remain neglected, making this study the first conservation initiative for “buga” in the region. Genetic diversity was high (H’=0.79), with multivariate analysis confirming unique accessions without duplication or clustering based on geographic origin. The study improved protocols for genebank establishment and management while recommending assembly of unrepresented accessions and strategies to strengthen in situ (on-farm) conservation through increased utilization.