Development of a Monoclonal Antibody for Detection ofLeptosphaeria korrae,the Causal Agent of Necrotic Ringspot Disease of Turfgrass

Abstract

Monoclonal antibody (MAb) LKc50 was developed against Leptosphaeria korrae strain ATCC 56289. The antibody was capable of detecting L. korrae from cultures and in naturally infected Kentucky bluegrass [Poa pratensis] samples from three states. In cross-reactivity tests using indirect ELISA, MAb LKc50 reacted positively to all 24 isolates of L. korrae screened, including strains from six states, from both Kentucky bluegrass and bermudagrass [Cynodon dactylon] MAb LKc50 reacted negatively ato 38 of 42 isoaltes of related and nonrelated fungi and negatively to apparently healthy grass. The limit of detection was less than 2 .mu.g/ml of lyophyilized mycelial homogenate. MAb LKc50 provides a means for rapid detection of L. korrae, an ectotrophic root-invading fungus that is difficult to identify using conventional methods.