Fusarium Culmorum Associated With Root Rot in Chickpea (Cicer Arietinum L.) in Uzbekistan: Molecular Identification and Pathogenicity

Root rot caused by Fusarium species is the major constraint in chickpea (Cicer arietinum L.) production under arid and semi-arid conditions of Central Asia.This study aimed to investigate the occurrence, pathogenicity, and molecular identity of Fusarium culmorum associated with chickpea root rot in Uzbekistan.During the growing season of 2025, collecting symptomatic chickpea plants transpired from fields in the Gallaarol District, Jizzakh Region, Uzbekistan, which yielded 10 Fusarium isolates.The selection of isolate GPEB-65 proceeded for detailed characterization.Morphological analysis revealed a rapid colony growth, reddish pigmentation, abundant chlamydospores, and the absence of microconidia, consistent with F. culmorum.The TEF1-α (translation elongation factor 1alpha) gene sequencing confirmed species identity, with 99.8% similarity to reference strains.Phylogenetic analysis placed the isolate GPEB-65 within a strongly supported Fusarium culmorum clade, confirming its taxonomic identity.Two unique single-nucleotide polymorphisms (A7G and C205T) distinguished the Uzbekistani isolate from strains reported in Iraq and the United States.Pathogenicity assays demonstrated the highest virulence, with severe root necrosis and a disease severity index (79%), fulfilling Koch's postulates through re-isolation.The results confirmed the presence of a highly virulent and genetically distinct F. culmorum population affecting the chickpea crop in Uzbekistan and provided a robust foundation for improved molecular monitoring and resistance breeding strategies.