Effects of nematode parasitism on mycophagous drosophilid species in northern Japan
Article first published online: 23 DEC 2009
© 2009 The Entomological Society of Japan
Volume 12, Issue 4, pages 363–369, December 2009
How to Cite
YOROZUYA, H. (2009), Effects of nematode parasitism on mycophagous drosophilid species in northern Japan. Entomological Science, 12: 363–369. doi: 10.1111/j.1479-8298.2009.00348.x
- Issue published online: 23 DEC 2009
- Article first published online: 23 DEC 2009
- Received 25 February 2009; accepted 18 May 2009.
- host–parasite interactions;
- long-term census
Mycophagous drosophilids and their nematode parasites were studied in an intensive census conducted throughout the active season over four years (2000–2003) in Hokkaido, northern Japan. Using census data, I assessed the prevalence of nematode parasitism through seasons, determined its effects on drosophilid female fertility and tested the “disproportionate parasitism hypothesis” to evaluate its effects on drosophilid community structure. Over the four-year census, a total of 43 fungal species were found on the census route and 18 177 adult drosophilid flies were collected. The yearly parasitism rate on the total drosophilid community varied from 6.2% in 2000 to 5.1% in 2001 and 3.0% in 2002 and 2003. There was strong seasonal variation in the prevalence of parasitism. In addition, parasitism rates varied among drosophilid species. All parasitized females carried only small numbers of eggs. Thus, nematode parasitism had a strong deleterious effect on the fitness of infected flies. The relative abundance of drosophilid species and parasitism rate were not significantly correlated. Thus, the disproportionate parasitism hypothesis likely does not apply to the mycophagous drosophilid community in Japan.