Survey and assessment of genetic diversity for yellow leaf disease, and DNA fingerprinting of Arecanut (Areca catechu L.) genotypes using molecular markers

Areca nut traditionally known for its stimulant properties, has gained recognition for its medicinal uses in treating schizophrenia and glaucoma, while also serving as a mild stimulant and digestive aid. Its production faces significant challenges, primarily from biotic stresses such as yellow leaf disease (YLD), particularly endemic in the Malnad region of Karnataka, India. Yellow leaf disease poses a substantial threat, causing heavy yield loss with no current cure; therefore, breeding for resistance is imperative. Disease-free palms identified in heavily affected regions may harbor unique gene families. This study utilized three marker systems viz., random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR), and resistant gene-based markers (RGP) to differentiate YLD-resistant areca palms from susceptible ones. The resistant gene primer (RGP) demonstrated the highest polymorphism, with a polymorphic information content (PIC) ranging from 0.45 to 0.83 and an average PIC of 0.72 among the arecanut genotypes. Other markers, OPAF 06, UBC 351, and RGP1, also exhibited significant polymorphism. The markers effectively differentiated susceptible and resistant genotypes into distinct clusters. The outcomes provide valuable insights for map-based cloning of YLD resistance genes. This molecular characterization lays the foundation for developing targeted treatments and diagnostics for YLD, emphasizing the importance of genetic approaches in securing areca nut production against this devastating disease.