Ingestion of Pythium spp. by larvae of the fungus gnat Bradysia impatiens (Diptera:Sciaridae)

Abstract

Mycelium, oospores and zoospore cysts of Pythium spp. were fed to larvae of the fungus gnat Bradysia impatiens. The fungal structures were all ingested and provided a complete nutritional source for the insect's development from egg to adult. Mycelium seemed the major source of food as only empty fragments were found either in the digestive tract or in larval faeces. Oospores appeared intact and were viable both during passage through the tract and when expelled. Germination of oospores was normal. Most encysted zoospores also survived passage through the gut, although some appeared damaged. After transferring recently-fed larvae to a new food source, oospores were still detected in the digestive tract 48 h later. These results show that the larval stage of B. impatiens may serve as an important vector for Pythium spp.

Sciarid and shore flies as aerial vectors of Fusarium oxysporum f. sp. cucumerinum in greenhouse cucumbers

“…Sciarid flies have also been reported to carry pathogens by trans-stadial transmission (Gardiner et al 1990;Jarvis et al 1993), involving ingestion of spores by root-feeding larvae. Some of the ingested spores remain viable in the digestive tracts after pupation and into the adult life stage, allowing the fungus to be spread through the faeces and carcass of the adult (Gardiner et al 1990;Jarvis et al 1993).…”

Molecular detection of fungi carried by Bradysia difformis (Sciaridae: Diptera) in South African forestry nurseries

“…cinerea to be of importance in the movement of these pathogens in a nursery. Fungus gnats have been reported to carry pathogens by trans-stadial transmission (Gardiner et al, 1990;Jarvis et al, 1993). For such transmission, the fungus gnat larvae feed on the spores of the fungi while living in the soil.…”

Life History Characteristics of the Rove Beetle,Dalotia coriaria(Coleoptera: Staphylinidae) under Laboratory Conditions

“…nr. coprophila (80 to 90 eggs per female for D. coriaria compared to 100 to 200 eggs per fungus gnat female) (Gardiner et al, 1990;Cloyd, 2008). This may limit the effectiveness of D. coriaria as a biological control agent unless higher numbers of predators are released; however, lower fecundity may not always indicate reduced effectiveness as it is possible that predators with lower fecundity may have higher predation rates thus resulting in their still being effective biological control agents.…”