The Role of Age in Intraspecific Interference of Neoseiulus californicus on Tetranychus urticae
Paper ID : 1108-IPCA5
Authors
Mahsa Nouri-Miri1, Katayoon Kheradmand *1, Yaghoub Fathipour2
1University of Tehran
2Tarbiat Modares University
Abstract
Neoseiulus californicus (McGregor) is a key predatory mite from the Phytoseiidae family, widely recognized for its effectiveness in managing greenhouse pests. As a type II generalist predator, it has been extensively applied in the control of thrips, eriophyid mites, and spider mites. One of the significant ways to recognize the efficacy of the phytoseiid predatory mites is the study of their foraging behavior. Mutual interference is a negative relationship between a predator's searching efficiency and its density. This study appraised the effect of the age-dependent mutual interference of N. californicus on larvae and nymphs of Tetranychus urticae Koch under laboratory conditions at 25 ± 1℃, 70 ± 5% RH and a photoperiod of 16L: 8D h. To determine the per capita searching efficiency and interference coefficient, Nicholson’s model and linear regression were used, respectively. The results showed that the total predation of N. californicus reared on T. urticae nymphs was significantly affected by predator density and age. In addition, per capita searching efficiency of the predator significantly declined with predator density, which is the result of mutual interference. Furthermore, the slope of the linear regression (m) between the logarithm of per capita searching efficiency and the logarithm of the predator density increased, ranging from -0.465 in 5-day-old individuals to -0.1452 in 40-day-old individuals. The negative effects of mutual interference decreased along with growing age. Our findings showed that in different tested ages, the rate of interference among adults differed compared to immature individuals. These results suggest that age-specific differences in mutual interference should be considered when optimizing the mass rearing and field release of predators for the biological control of T. urticae.
Keywords
Biological control, Mass rearing, Mutual interference, Phytoseiid mite, Predator density
Status: Abstract Accepted