Genetic Characterization of Barley Yellow Dwarf Virus (BYDV) Isolates and Their Aphid Vector Associations

Abstract

Genetic characterization of Barley Yellow Dwarf Virus (BYDV) isolates and their aphid vector associations was conducted to elucidate viral diversity and transmission relationships in cereal agroecosystems. Field surveys were carried out in infected cereal crops, and symptomatic plant samples exhibiting yellowing, stunting, and chlorosis were collected for virus detection. Molecular identification of BYDV isolates was performed using RT-PCR and sequencing of coat protein and associated genomic regions to determine genetic variability and phylogenetic relationships. Sequence analysis revealed significant genetic diversity among BYDV isolates, clustering into distinct strains corresponding to known viral groups, indicating multiple introductions and localized evolution. Phylogenetic reconstruction demonstrated clear differentiation among isolates, reflecting both geographic distribution and host adaptation patterns. Concurrent sampling of aphid populations identified dominant vector species, with variation in virus transmission efficiency linked to aphid species composition and abundance. Strong associations were observed between specific aphid vectors and particular BYDV strains, suggesting vector–virus specificity in transmission dynamics. Epidemiological patterns indicated that aphid population density and seasonal migration played a critical role in disease spread across cereal fields. The integration of molecular and vector ecology data provided a comprehensive understanding of BYDV epidemiology. These findings highlight the importance of monitoring both viral genetic variability and aphid vector populations for effective management of Barley Yellow Dwarf disease in cereal production systems.