Detection of Peanut Stripe Virus in Peanut Seed by an Indirect Enzyme-Linked Immunosorbent Assay Using a Monoclonal Antibody. J. N. Culver, Department of Plant Pathology, Oklahoma State University, Stillwater 74078-0285. J. L. Sherwood, Department of Plant Pathology, Oklahoma State University, Stillwater 74078-0285. Plant Dis. 72:676-679. Accepted for publication 17 February 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-0676.

Indirect and double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) formats, using polyclonal antibodies alone, monoclonal antibodies (MAB) alone, or the two in combination, were compared for the detection of peanut stripe virus (PStV) in peanut seed. The MAB indirect ELISA format was shown to be the most sensitive, detecting 2.5 ng/ml of virus and detecting one PStV-infected seed part diluted in 32 healthy seed parts. The MAB indirect ELISA was also used to screen seed from the PStV-infected peanut cultivars Spanco, Pronto, Tamnut 74, Argentine, and Florunner. A small portion of cotyledon from each seed was removed and tested for PStV by the MAB indirect ELISA without adversely affecting the seed’s viability. The seeds were then planted and the resulting seedlings tested for PStV infection by ELISA, symptomatology, and local lesion assay on Chenopodium amaranticolor. The MAB indirect ELISA readily detected PStV antigen in peanut cotyledonary tissue. Seeds determined to be virus-free by the MAB indirect ELISA always produced virus-free seedlings. However, a few seeds determined to have detectable amounts of PStV antigen by the MAB indirect ELISA also produced virus-free seedlings. All five peanut cultivars were shown to transmit PStV by seed at rates ranging from 0.4 to 5.0%.