Banana bract mosaic virus (BBrMV) is a serious pathogen threatening the cultivation of banana and plantain worldwide. This study reports the development of a practical, rapid, sensitive, specific and user-friendly lateral flow immunoassay (LFIA) test for the on-site detection of BBrMV. The BBrMV coat protein (CP) was expressed in Escherichia coli and purified and used to immunize rabbits to produce a polyclonal antiserum (anti-BBrMVCP). The test was based on a double-antibody sandwich format. Protein-A affinity column-purified anti-BBrMVCP Immunoglobulins (IgG) (16 μg/mL), conjugated to ∼30 nm gold nanoparticles, was applied onto the conjugate pad. The anti-BBrMVCP IgG and goat anti-rabbit IgG were printed on the surface of a nitrocellulose filter membrane as the test line and control line, respectively. A positive result could be confirmed visually by the presence of a pink band that developed on the LFIA strip within 5−10 min. The detection limit of the test was 10 ng of the expressed recombinant BBrMV CP (rBBrMVCP), and a 1:20 dilution of the BBrMV-infected crude extract. This LFIA test was validated using 114 banana leaf samples randomly collected from the field and the results indicated a very high diagnostic sensitivity (99.04 %) and specificity (100 %) for the test. A Cohen's kappa coefficient of 0.861 obtained also indicated a very good agreement between the LFIA developed in this study and ELISA. This assay could be adopted by farmers, tissue culture industries and quarantine departments for surveys and surveillance. This is the first report on the development of a LFIA-based test for BBrMV detection.

香蕉片花叶病毒（BBrMV）是一种严重的病原体，威胁着全世界香蕉和车前草的种植。这项研究报告了一种用于现场检测BBrMV的实用，快速，灵敏，特异且用户友好的侧流免疫测定（LFIA）测试的开发。BBrMV外壳蛋白（CP）在大肠杆菌中表达纯化后用于免疫兔以产生多克隆抗血清（抗BBrMVCP）。该测试基于双抗体夹心形式。将蛋白A亲和柱纯化的抗BBrMVCP免疫球蛋白（IgG）（16μg/ mL）与约30 nm的金纳米颗粒偶联，然后应用到偶联垫上。将抗BBrMVCP IgG和山羊抗兔IgG分别印刷在硝酸纤维素滤膜的表面上作为测试线和对照线。可以通过在5-10分钟内在LFIA试纸条上出现一条粉红色条带在视觉上确认阳性结果。该测试的检测限为10 ng表达的重组BBrMV CP（rBBrMVCP）和1:20稀释的BBrMV感染的粗提物。使用从田间随机收集的114个香蕉叶样品验证了此LFIA测试，结果表明该测试具有很高的诊断敏感性（99.04％）和特异性（100％）。获得的Cohen卡伯系数为0.861，也表明该研究开发的LFIA与ELISA之间有很好的一致性。农民，组织文化产业和检疫部门可以采用这种测定方法进行调查和监视。这是关于开发基于LFIA的BBrMV检测测试的第一份报告。组织文化产业和检疫部门进行调查和监视。这是关于开发基于LFIA的BBrMV检测测试的第一份报告。组织文化产业和检疫部门进行调查和监视。这是关于开发基于LFIA的BBrMV检测测试的第一份报告。