Development and evaluation of a colloidal gold immunochromatographic assay for rapid on-site detection of cucumber mosaic virus

Cucumber mosaic virus (CMV) globally causes substantial yield reduction and economic losses across a wide range of crops. Current diagnostic methods predominantly rely on laboratory-based techniques requiring stringent laboratory conditions and specialized expertise, limiting practicality for field-based detection. To address these limitations, we developed a novel colloidal gold-based immunochromatographic assay (CGIA) for rapid and reliable CMV detection. Through systematic optimization of key parameters, the assay achieved optimal performance with 0.5 μg/mL coating antigen and 0.5 mg/mL quality control antigen, and the minimum detectable concentration of the gold-conjugated antibody was determined to be 0.25 mg/mL. Validation studies demonstrated the test strip's ability to deliver reliable results through visual interpretation within 10 min. This field-deployable platform offers distinct advantages, including operational simplicity and adaptability to environmental conditions. The developed assay represents a significant advancement in plant viral diagnostics by eliminating the need for specialized laboratory infrastructure while maintaining analytical reliability, providing an essential tool for implementing timely phytosanitary interventions in resource-limited environments.