Species and Occurrence of Parasitoids of Cnaphalocrocis medinalis in Nanning, Guangxi, China.

[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]