Functional Response and Predation Interference of Neoseiulus californicus (Acari: Phytoseiidae) on Tetranychus urticae Nymphs: Influence of Plant Pollens as Supplemental Food Sources

Pollens provide important nutrients and help in the reproduction process for many predators. Neoseiulus californicus (McGregor) is one of the important and useful predators of the two-spotted spider mite. The response of three-day-old mated N. californicus female predatory mite fed by pollens (marshmallow, sunflower and tamarix) to different densities (۲, ۴, ۸, ۱۶, ۳۲, ۴۵ and ۶۴ numbers) of the prey (the second instar nymphs of two-spotted spider mite) and interference in different densities (۱, ۲, ۴, ۸, and ۱۶ numbers) of the predator and a fixed prey density (۴۰ number) were studied in ۱۰ replications on bean leaf discs. The experiment conditions included a temperature of ۲۷±۱ °C, relative humidity of ۷۰%, and a photoperiod of ۱۶:۸ h (light: darkness). The type of functional response and its parameters were calculated using logistic and non-linear regression. According to the results of the logistic regression, the functional response was type II. The attack coefficient and handling time were calculated on marshmallow pollen (۰.۴۳ per h and ۴.۰۱ h), tamarix pollen (۰.۴۳ per h and ۴.۰۳ h) and sunflower pollen (۰.۴۲ per h and ۴.۰۲ h). The predatory ability in predation of the second instar nymph of the two-spotted spider mite on marshmallow and tamarix pollen was greater than that of sunflower pollen. Considering that the nutritional value of plant pollens is different, the relationship between the logarithm of predator density and the per capita attack coefficient was significant in the marshmallow and tamarix pollens. The predation rate of N. californicus increased with increasing density of the two-spotted spider mite. There was a significant relationship between the logarithm of predator density and the logarithm of per capita attack coefficient (calculated by the Nicholson equation). The predatory rate of N. californicus increases with increasing density of two-spotted spider mite nymphs and decreasing predator density. The predatory mite N. californicus reared on the mentioned plant pollens greatly controlled the two-spotted spider mite.

کلیدواژه ها:

Attack coefficient ، marshmallow ، tamarix ، sunflower pollen ، predator efficiency