Development of Molecular Markers to Detect Diaporthe spp. from Decayed Soybean Seeds

Soybean is one of the world's most widely cultivated food crops, and soybean seeds are supplied from national seed resources in Korea. However, the transmission of seed-borne diseases through infected soybean seeds is problematic. Among these diseases, soybean seed decay is caused by Diaporthe spp. Infecting the pods, and the infected seeds show rotting symptoms. Most diseased seeds are removed during the selection process; however, it is difficult to distinguish infected seeds that do not display symptoms. Hence, a sequence-based method was devised to screen Diaporthe-infected seeds. Based on the nuclear ribosomal internal transcribe spacer (ITS) region of the pathogen, a primer was designed to distinguish the infection from other soybean seed pathogens. As a result of the comparison between healthy and Diaporthe-diseased seeds by using the primers, Diaporthe was detected only in the diseased seeds. Therefore, it is possible to distribute healthy soybean seeds by detecting Diaporthe-diseased seeds at the genetic level using the Diaporthe-specific primers.