Epidemiology and Spatial Distribution of Citrus Tristeza Virus in Citrus Orchards Using Serological Methods

Abstract

Epidemiological patterns and spatial distribution of Citrus Tristeza Virus (CTV) were investigated in citrus orchards using serological detection techniques to understand disease incidence and spread dynamics. Field surveys were conducted across multiple orchard blocks, and leaf samples were collected from symptomatic and asymptomatic citrus trees. Virus detection was performed using enzyme-linked immunosorbent assay (ELISA), enabling reliable identification of CTV-positive samples. Disease incidence varied significantly among orchard locations, reflecting heterogeneity in vector activity, host susceptibility, and orchard management practices. Spatial analysis revealed aggregated distribution patterns, indicating localized disease clusters rather than uniform spread. Higher infection levels were associated with older orchards and areas with dense planting, suggesting favorable conditions for aphid-mediated transmission. Serological results confirmed the presence of CTV even in asymptomatic plants, highlighting latent infections contributing to unnoticed pathogen persistence. Environmental and agronomic factors, including vector abundance, irrigation practices, and host cultivar composition, influenced disease intensity and distribution. The study emphasizes the importance of integrating serological diagnostics with spatial mapping approaches for accurate disease surveillance. Understanding the epidemiology of Citrus Tristeza Virus is essential for early detection and effective management strategies, including vector control and use of resistant rootstocks. These findings provide a foundation for developing region-specific disease management programs aimed at reducing the impact of CTV on citrus production systems.