Parasitization behavior and its time allocation of Iseropus kuwanae

Iseropus kuwanae is a dominant parasitic wasp in mulberry fields, but its parasitization behavior has not been thoroughly documented. Using Galleria mellonella as the host, this study aimed to provide a detailed characterization of the parasitization behavior of I. kuwanae.

The parasitization process of I. kuwanae was observed in the parasitic box, and the behavior characteristics and time allocation of female wasps during parasitism were recorded. Finally, the differences and correlations among the behavioral variables were analyzed using the Kruskal-Wallis rank-sum test, multiple comparisons, and bivariate correlation analysis.

The parasitism behavior of I. kuwanae mainly included two main stages: pre-oviposition stage and ovipositing stage. The pre-oviposition stage included host locating, checking, stinging, and waiting. The ovipositing stage included checking, stinging and oviposition. In the pre-oviposition stage, checking and stinging occurred most frequently, and the number of checking events was significantly correlated with the number of stinging events. Female I. kuwanae oviposited on the same host more than once, and the number of eggs laid ranged from 5 to 24. The number of eggs laid was significantly correlated with the oviposition duration. When the oviposition duration did not exceed 25 minutes, the number of eggs laid increased with longer oviposition duration, but after the oviposition duration exceeded 25 minutes, the number of eggs laid decreased sharply.

The time allocated to different behavioral processes during parasitism by I. kuwanae decreased in the following order: oviposition, waiting, host locating, checking, and stinging. Oviposition accounted for the longest duration, representing 36.8% of the total parasitization time. There were significant correlations among the variables of oviposition behavior.