1887

n African Entomology - The incidence of (Linnaeus) (Hymenoptera : Formicidae) and parasitoids (Hymenoptera : Braconidae) as mortality factors of Fuller (Lepidoptera : Noctuidae) and (Swinhoe) (Lepidoptera : Crambidae) in Lesotho

USD

 

Abstract

Predatory ants and parasitoids of the stemborers Fuller (Lepidoptera : Noctuidae) and (Swinhoe) (Lepidoptera : Crambidae) were collected during field surveys conducted in the 1995 / 96 and 1996 / 97 seasons in Lesotho. Parasitoids (Hymenoptera : Braconidae) and (Linnaeus) (Hymenoptera : Formicidae) were sampled at regular intervals in field trials. Two braconid species, Cameron and (Cameron), were found to parasitize both and larvae in maize and sorghum. Two other species, sp. and (Wesmael), were reared from larvae. was the most abundant and widespread of the four larval parasitoids. Pupal parasitism was rare. Egg parasitism was not observed. was found to be an important and widely distributed predator of both and larvae. Parasitism of by was higher in sorghum than in maize. Parasitism levels were generally low during the season except during April and May, when 21 % and 31 % parasitism was recorded on sorghum in the 1995 / 96 and 1996 / 97 seasons, respectively. Because the activities of natural enemies increased only towards the end of the growing season, they are unlikely to exert a pronounced effect on stemborer populations during the growing season. They may, however, play an important role in reducing the size of overwintering populations.

Loading

Article metrics loading...

/content/ento/9/1/EJC29845
2001-03-01
2016-12-02
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error