Banker boxes, a novel release method, improve the biological control of Planococcus citri by Cryptolaemus montrouzieri and Leptomastix dactylopii in pomegranate

Abstract

A study was conducted to determine the efficacy of a predator, Cryptolaemus montrouzieri (Muls.) (Coleoptera: Coccinellidae) and a parasitoid, Leptomastix dactylopii (How.) (Hymenoptera: Encyrtidae), in biological control of citrus mealybug Planococcus citri Risso (Hemiptera: Pseudococcidae), a major pest in pomegranate orchards in Antalya. When the pests were observed in 2013, 10 predators and 20 parasitoids were concurrently released per tree in plots using the standard procedures. In 2014 and 2015, despite the partial control (74%) in 2013, a different method release method was used; a modified banker box. In this method, beneficial insects were established in cardboard boxes that included potato tubers infested with prey pest before release. These boxes were then placed in the orchard before pest seen. The total number of beneficials in three boxes was equal to the number of beneficials released in 2013. The banker box method gave promising results, with control of nearly 90% in both 2014 and 2015. These findings demonstrated that the banker box application increased the effectiveness of the release of beneficials and it suggested that this method should be considered for biological control of citrus mealybug in pomegranate.