age-specific functional response of aphidius matricariae and praon volucre (hym.: braconidae) on aphis gossypii (hem.: aphididae)

the cotton aphid, aphis gossypii glover is a major pest of greenhouse cucumber in the world. in this study, age specific functional response of aphidius matricariae haliday and praon volucre (haliday) were investigated on a. gossypii at 25±1°c, 60±5% rh and a photoperiod of 14 l: 10 d h. the results showed that the functional response of a. matricariae was type iii during 1st, 2nd, 3rd, 4th and 5th days and type ii in 6th day of adult parasitoid lifetime. the type of functional response of p. volucre was type ii in whole parasitoid lifetime. the highest b value (0.02±0.003 h-1) and the lowest handling time (th) (0.70±0.013 h) of a. matricariae were observed in the 1st day of parasitoid lifetime. the maximum attack rate (t/th) of a. matricariae occurred in the first day of parasitoid lifetime (34.28 nymphs). the maximum searching efficiency of p. volucre was determined in the 2nd and 3rd days (0.03±0.003 and 0.03±0.005 h-1) and the minimum handling time was recorded in the 2nd day (0.97±0.140 h) of adult female life. the maximum parasitism rate was 24.74 nymphs in the two day old female, and then decreased in adult female age. the results suggest that a. matricariae and p. volucre are highly effective biological agents in suppressing a. gosspii population on cucumber in greenhouses.