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[Objective] To specify the parasitoid species of Cnaphalocrocis medinalis in Nanning, Guangxi Zhuang Autonomous Region, and provide theoretic references for the reasonable utilization and using natural enemy. [Method] Field investigation and indoor rearing observation were adopted to figure out species and quantity of parasitoids of C. medinalis in Nanning in 2011 -2013. [Result] There are 19 parasitoid species of C. medinalis in Nanning, belonging to Ich-neamonoidea, Chalcidoidea. Of Ichneamonoidea, there are 11 species from Ichneumonidae and Braconidae. Of Chalcidoidea, there are 8 species from Chalcididae, Eulophidae, Elasmidae, Trichogrammatidae and Encyrtidae. Among these species, Stenomesius macidatus Liao and Apanteles cypris Nixon are dominant parasitoids in larval stage. In natural control conditions, S. maeulatus Liao is most-widely distributed species with the most population, especially in the first half year, accounting for 89.7% of the total parasitoid quantity; in pesticide application field, the quantity of S. macidatus Liao accounts for 69.1% of the total parasitoid quantity, and in nonpesticide field, it accounts for 78.5%. [Conclusion] Application of chemical pesticide has serious impact on the natural populations of parasitoids, therefore, chemical pesticides should be applied reasonably to ensure the survival of parasitoids. [ABSTRACT FROM AUTHOR]

Aspergillus section Flavi is widely known as a potential threat to contaminate agricultural products and food commodities. In this study, a polyphasic approach consisting of micro- and macro-morphological, chemical and molecular features, was applied to survey the Aspergillus section Flavi population in corn collected from Guangxi, China. Based on multigene phylogenies as well as morphological observations, Aspergillus flavus (192/195), A. arachidicola (1/195), A. pseudonomius (1/195) and A. novoparasiticus (1/195) were found to be the predominant section Flavi population. Among them, 31 representative isolates were selected for mycotoxin determination. The results showed that Aspergillus flavus chemotype I was most common, chemotype IV was also detected with low incidence and low CPA amounts, while chemotypes II and III were absent. Other tested species including A. arachidicola , A. pseudonomius , and A. novoparasiticus produced all types of aflatoxins, but none of them produced CPA. The polyphasic approach applied in this study permitted reliable understanding of the prevailing Aspergillus section Flavi population and their mycotoxin profiles. Knowledge of the prevailing section Flavi population will aid in developing a sustainable strategy to mitigate the effects of aflatoxin contamination. This study suggests that CPA contamination of food should be considered while conducting mycotoxigenic surveys of food commodities, and the same should be considered while planning a bio-control strategy to control aflatoxin contamination. • An elevated amount of cyclopiazonic acid is produced in co-occurrence with aflatoxins. • Cyclopiazonic acid should be considered as a potentially toxic contaminant in toxigenic surveys of Aspergillus flavus. • A polyphasic approach was applied to identify the isolates of Aspergillus Section Flavi originating from Guangxi, China. [ABSTRACT FROM AUTHOR]