Mycoflora of stored rice in relation to the biological control of Sitophilus oryzae by Anisopteromalus calandrae

In this study, we determined the effect of controlling rice weevils on the mycoflora of stored brown rice by using Anisopteromalus calandrae (Howard), a parasite of the rice weevil. The mycoflora in brown rice with the parasitoid was similar to that without the parasitoid; however, the dominant mold species differed. Without the parasitoid, Aspergillus candidus Link and Penicillium islandicum Sopp were the dominant species, whereas Aspergillus penicilloides Speg. and P. islandicum were dominant when the parasitoid was present. The difference appeared to be due mainly to the difference in the grain moisture content with and without the parasitoid. A. candidus was the dominant species in the communities without the parasitoid and was not observed when the weevils were suppressed. P. islandicum dominated or co-dominated regardless of the presence of the parasitoid which suggested that P. islandicum is tolerant to low grain moisture content or is positively affected by the presence of the rice weevil.

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► The dominant mold species in brown rice with and without the parasitoid were different from each other.
► The difference appeared to be due to the differences in the grain moisture content.
► P. islandicum might be tolerant to low grain moisture content.
► P. islandicum dominated regardless of the presence of the parasitoid.