SENSITIVE BROAD-SPECTRUM DETECTION OF INDIAN PEANUT CLUMP VIRUS BY NONRADIOACTIVE NUCLEIC-ACID PROBES

Cloned cDNA fragments representing different regions of the genome of the ii serotype of Indian peanut clump furovirus (IPCV) were used as h ybridization probes. Dot-blot assays using digoxigenin-labeled probes readily detected IPCV in extracts from infected plants with a sensitiv ity approaching that of using P-32-labeled probes. The specificity of the probes depended on the part of the IPCV genome represented in the cDNA. Two probes representing the coat protein gene and adjacent gene in RNA-2 readily detected infection by H serotype IPCV, but reacted po orly with samples of plants infected with other serotypes. A probe cor responding to sequence near the 5'-end of RNA-1 reacted with samples o f all IPCV serotypes, but not with those of peanut clump virus (PCV) f rom West Africa. A probe corresponding to the 3'-terminal 742 nucleoti des of RNA-1 readily detected RNA of any IPCV serotype and of PCV. Ass ays using this probe, labeled with a nonradioactive reporter-digoxigen in, could detect IPCV in samples of seed tissue, as well as in tissue of several weed species and crop species such as wheat. The probe did not react with samples from plants infected by other furoviruses.