Detection of a plant pathogen in a nonvector insect species by the polymerase chain reaction

A nonculturable mycoplasmalike plant pathogen was detected in a leafhopper species capable of transmitting the pathogen as well as in a leafhopper species that does not vector the pathogen. Amplification of a pathogen-specific DNA sequence by polymerase chain reaction (PCR) revealed the presence of pathogen DNA in total nucleic acid extracts of the vector insect Macrosteles fascifrons and of the nonvector insect Dalbulus maidis, both of which had fed on plants infected by the aster yellows mycoplasmalike organism