Predatory capacity of Lasioseius lindquisti (Acari: Blattisociidae) and Lasioseius scapulatus (Acari: Blattisociidae) on Megalurothrips usitatus (Thysanoptera: Thripidae)

Megalurothrips usitatus (Bagnall) (Thysanoptera: Thripidae) is an important pest of cowpeas, Vigna unguiculata (L.) Walp., and can cause severe damage to the crop. Lasioseius lindquisti (Tseng) (Acari: Blattisociidae) and Lasioseius scapulatus (Kennett) (Acari: Blattisociidae) are 2 mites used against M. usitatus in Hainnan, China. The functional responses of these mites were examined in the laboratory. Lasioseius lindquisti showed a type III functional response, with a maximum prey consumption of 22.38 ± 0.63 per day. Its optimal search density for each unit in this experiment was 10.27 ± 0.50 per day. Lasioseius scapulatus showed a type II functional and an attack rate on 1st instars of M. usitatus of 0.83 ± 0.23. The handling time (h) of L. scapulatus was 0.074 ± 0.018 (means ± SE), while the maximum attack rate (T/Th) of adult females on 1st instar thrips was 13.51. Our results showed that both L. lindquisti and L. scapulatus are potentially useful predators of M. usitatus.