| Nymphs and adults of Lygus species, mainly L. rugulipennis Poppius were collected from wheat fields in southern Finland, near Helsinki. The parasitization rate of braconid species was determined by dissection of the hosts. Parasitoids were reared from separate samples from the same fields.The parasitization rate was low, the maximum percentage occurring during the season, examined in 10-day periods, was 14%. All nymphal instars, except the first one, were found to be parasitized; the mean varied from 3% (third instar) to 6.5% (fourth instar). In adult hosts the mean parasitization rate was 2% in males and 4% in females. The percentage of parasitization in both nymphs and adults was higher in wheat bordering fields with a mixture of field bean and oats or... |
