Submitted to: Molecular Plant-Microbe Interactions
Publication Type: Abstract Only
Publication Acceptance Date: 7/14/1996
Publication Date: N/A
Technical Abstract: Phomopsis spp. are important soybean pathogens that cause blight, stem canker and seed decay. Primers corresponding to conserved sequences of the ribosomal DNA were used for PCR to amplify the internal transcribed spacer (ITS) regiongs of Phomopsis. After direct gel purification, the ITS regions of 10 Phomopsis strains isolated from soybean from 5 states were sequenced and aligned. Phomopsis-specific primers were designed to the polymorphism regions. DNA was extracted from soybean plants and 9 other soybean fungal pathogens grown in liquid culture medium. All these DNA showed clear bands with the same or different DNA fragment lengths when amplified with ITS4 and ITS5 primers, but only the DNA from Phomopsis showed a strong band (about 400 bp in length) when amplified with Phomopsis specific primers. These specific primers were also applied to detect Phomopsis from infected soybean seedlings and seeds and demonstrated that PCR-based technique with the specific primers is faster and more sensitive than traditional plate examination.