Propagational characteristics of the entomophagous and mycetophagous nematode, Contortylenchus genitalicola (Tylenchida: Allantonematidae), on an unidentified fungus

Abstract

Contortylenchus genitalicola, an entomophagous and mycetophagous nematode, was cultured on an unidentified fungus and the propagational characteristics were investigated so as to be employed for a biological control agent against the Japanese pine sawyer which transmits the pine wood nematode, Bursaphelenchus xylophilus, a causal agent of the pine wilt disease. Culture media which were substrates for fungus and nematodes, incubation period and temperature affected the propagation of nematodes. For the first 15 days, the number of C. genitalicola increased linearly and proportionally to the growth of fungus irrespective of the composition of media tested. After 30 to 45 days, numbers of nematodes propagated varied with the kind of media. The nematodes propagated themselves most rapidly at 25°C, while they did not at 5 to 15°C and died at 35°C. Since propagation of C. genitalicola was poor on the full-grown mycelium the nematodes seemed to feed on the growing edges of fungal hyphae. Both nematode propagation and fungal growth were depressed by the repeated subculture for 3 years or more. Jpn. J. Nematol. 25 (2): 77-84 (1995: publ. 1996).