Population density and parasitism rate of Lymantria dispar L. (Lepidoptera: Lymantriidae) during a five-year survey in a Sardinian cork-oak forest
Cerboneschi, A.
Bulletin OILB/SROP 22(3): 129-136
1999
ISSN/ISBN: 1027-3115 Accession: 003528537
A five-year (1994-98) survey was carried out in a cork-oak (Quercus suber) forest of north-east Sardinia, to estimate the trend in Lymantria dispar population dynamics and to provide useful information about L. dispar control. The population density was evaluated by counting the egg-masses on a group of 40 cork-oak trees. Each year, several egg-masses were collected to determine L. dispar fecundity and fertility. A laboratory study was conducted to investigate the parasitism rates for larvae and pupae. The average weight of fresh pupae was also calculated for each sample. The incidence of the parasitoid species recovered from insects collected in the field and reared in laboratory was assessed. The data concerning egg-mass density were compared and examined in relation to the results of the survey carried out on the parasitism and to the fresh weight of pupae. The results are presented.