Abstract:
In order to clarify the overwintering sites and diapause traits of
Aphidius gifuensis in fields in central Henan Province, the overwintering of parasitized aphids of
A. gifuensis in fields was investigated.
A. gifuensis samples collected from the fields were identified to analyze the diapause traits and status of
A. gifuensis. The results showed that
A. gifuensis mainly overwintered on cabbage and radish in the form of parasitized aphids, while a few overwintered on rape, wheat and other crops in the fields. Adult parasitoids could not overwinter. The proportion of overwintered pupae in the parasitized aphids was on average of 47.95%, followed by mature larvae in aphids, with an average of 41.48%, while a few
A. gifuensis overwintered as pre-pupae in the aphid. From November to mid-March of the following year, the diapause rate of
A. gifuensis in the fields increased first and then decreased generally, the highest diapause rate reached 64.0%, and the duration of diapause maintained from three to five months.