Predation Capability and Functional Response of Chrysoperla carnea1 to Choristoneura rosaceana2 under Laboratory Conditions.

Functional response of third-instar larvae of green lacewing, Chrysoperla carnea (Stephen) (Neuroptera: Chrysopidae), to four densities of single-instar larvae of the five instars of obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), was evaluated at 25 ± 1°C in a laboratory. The aims were to determine the type and other characteristics of functional response including predatory capacity of green lacewing for possible use in augmentative biological control in apple ( Malus × domestica Borkh; Rosales: Rosaceae) orchards where obliquebanded leafroller was recently introduced in Mexico. Abundance of the pest increased rapidly, causing significant foliar damage and some fruit blemish. Third-instar green lacewing larvae based on logistic regression analysis showed Type II functional response to four densities of single-instar larvae of obliquebanded leafroller. Among the five instars of prey, the largest average number consumed per green lacewing predator was a relative density of four second-instar larvae at a rate of 1.93 in 24 hours. Also, substantial average consumption was by two third-instar prey larvae per predator whereby an average of 1.5 third-instar obliquebanded leafrollers were consumed per third-instar green lacewing in 24 hours. The third-instar predator captured and consumed third-instar prey larvae in the shortest handling time ( h), i.e., only 6.46 minutes, whereas the handling times for the other instars ranged from 23.48 minutes for the fifth instar to 31.56 minutes for the fourth instar. However, attack coefficients ( a) of green lacewings were slightly greater for third- and fourth-instar prey larvae, with 0.19 hour (11.4 minutes) and 0.15 hour (9.0 minutes) until the first attack, respectively, compared to 0.09-0.11 hour (5.4-6.6 minutes) until the first attack for the other instars. Results indicated that the green lacewing could be considered a prospective candidate for use as a biological control agent against lepidopteran leafrollers. [ABSTRACT FROM AUTHOR]