Plum pox virus(PPV)is a quarantine pathogen in China.It is the causal agent of sharka or plum pox,probably the most serious viral disease affecting trees of the genus Prunus.It causes important losses in crop yield,as high as 95%in very susceptible varieties and presents a broad geographic distribution,including Europe,Egypt,Syria,Chile and India and so on.PPV belongs to the Potyvirus genus of plant viruses and has a single-stranded RNA genome of positive sense.This is translated into a single polyprotein that is further processed by vira l-coded proteases.The genomic RNA is surrounded by approximately 2000 units of a single type of capsid protein(CP)that is encoded at the end of the genome,forming helicoidal virions.The CP gene of Plum pox virus was obtained by RT-PCR and inserted into pET29(a)vector to formed recombination pET29a-PPV which was then transformed into E.coli strain BL21(DE3),the CP gene was expressed effectively after inducing with IPTG.Specific antiserum was got from rabit immouned with expressed CP and the titer was 4×103 assayed with ID-ELISA.The immune colloidal gold test strip for Plum pox virus was developed with the antiserum and test results showed that the specificity、stability and sensitivity of the strip were satisfied.The crude purified virus in concentration 1μg/mL or dilued by 100 times of the infected plants could be detected.The test results could appear in 10min with simple steps.The strip was suitable for port quarantine and rapid test on the spot.