Isolation and Identification of Fungal Species from the Insect Pest in Rice Processing Complexes in Korea.

The red flour beetle, , is one of the most common and economically important pests of stored cereal products worldwide. Furthermore, these beetles can act as vectors for several fungal post-harvest diseases. In this study, we collected from 49 rice processing complexes (RPCs) nationwide during 2016-2017 and identified contaminating fungal species on the surface of the beetles. Five beetles from each region were placed on potato dextrose agar media or selection media after wet processing with 100% relative humidity at 27°C for one week. A total of 142 fungal isolates were thus collected. By sequence analysis of the internal transcribed spacer region, 23 fungal genera including one unidentified taxon were found to be associated with . The genus spp. (28.9%) was the most frequently present, followed by spp. (12.0%), (9.2%), spp. (8.5%), spp. (6.3%), spp. (5.6%), spp. (3.5%), (2.8%) and sp. (2.8%). Less commonly identified were genera , , , , , , , , , , , , , and . Among the isolates, two known mycotoxin-producing fungi, and spp. were also identified. This result is consistent with previous studies that surveyed fungal and mycotoxin contamination in rice from RPCs. Our study indicates that the storage pest, , would play an important role in spreading fungal contaminants and consequently increasing mycotoxin contamination in stored rice.