age-specific functional response of psyllaephagus zdeneki (hymenoptera: encyrtidae), parasitoid of euphyllura pakistanica (hemiptera: psyllidae)

this study was conducted to evaluate the age-specific functional response of psyllaephagus zdeneki noyes & fallahzadeh (hymenoptera: encyrtidae) at different nymph densities of olive psyllid, euphyllura pakistanica loginova (hemiptera: psyllidae). due to parasitoid behaviour of feeding and parasitizing the host, both traits were separately explored on a daily functional response. results of logistic regression revealed a type ii functional response of the wasp independent of their ages. the handling time (th) and searching efficiency (a) were estimated using the rogers equation. the highest searching efficiency for both parasitism and feeding was observed in the first five days of the adult age. the handling time for parasitism and host feeding increased with the age of female wasp. the highest searching efficiency and shortest handling time for host attacked (parasitism and feeding) were gained in day 5 and day 2 and maximum parasitism and host feeding in days 2 and 3 of adult female age, respectively. we conclude that p. zdeneki demonstrated a reasonable performance as a potential biocontrol agent by feeding and parasitism of e. pakistanica which gained its maximum efficiency within 2 to 5 days of its life.