Activity-density of Pardosa cribata in Spanish citrus orchards and its predatory capacity on Ceratitis capitata and Myzus persicae

The wolf spider Pardosa cribata Simon is the most abundant ground-dwelling spider inhabiting citrus orchards in eastern Spain. However, little is known about its activity-density and its predatory role in the citrus agrosystem. Here we report on the activity-density of P. cribata monitored by pitfall traps, and on its capacity to prey on two citrus pests that appear both in the citrus canopy and the ground cover, Ceratitis capitata (Wiedemman) and Myzus persicae (Sulzer), respectively. Pardosa cribata was present in citrus orchards throughout the year, with a peak in spring and a higher peak in summer. Pardosa cribata preyed on adults and third-instar larvae but not on pupae of C. capitata. A type II functional response was obtained for teneral-like adults, with an estimated attack rate (a') of 0.771 +/- A 0.213 days(-1) and a handling time (T (h)) of 0.051 +/- A 0.013 days. Pardosa cribata also preyed efficiently on M. persicae, giving a type II functional response with an estimated attack rate and handling time of 2.833 +/- A 0.578 days(-1) and 0.031 +/- A 0.001 days, respectively. The data reported here indicate that this wolf spider could play an important role in regulating both these pests, and therefore might contribute to developing conservation biological control strategies for citrus pests