Two-Spotted Ladybeetle Adalia bipunctata L. (Coleoptera: Coccinellidae): A Commercially Available Predator to Control Asian Citrus Psyllid Diaphorina citri (Hemiptera: Liviidae)

Abstract

The Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Liviidae) is an economically important pest of citrus because it serves as a vector of the causal pathogens of huanglongbing (HLB) also known as citrus greening disease. The increased use of insecticides for control of D. citri negatively impacts several natural enemies including some effective ladybeetle species which are not available commercially. The two-spotted ladybeetle, Adalia bipunctata (Coleoptera: Coccinellidae) is found in some crop and forest ecosystems of Asia, Europe and North America and available commercially. It is known to attack aphids and mealybugs but there are no published records of feeding on psyllids. We evaluated suitability and preference of A. bipunctata for nymphs of D. citri compared to corn leaf aphid Rhopalosiphum maidis (Hemiptera: Aphididae) a global pest of cereal crops and prey for many predaceous insects. We also compared development and reproduction of A. bipunctata on these two species with frozen eggs of the Mediterranean flour moth Ephestia kuehniella (Lepidoptera: Pyralidae) at 25°C. Initially, more D. citri than R. maidis nymphs were consumed in the no-choice tests although final consumption by larva and adult of A. bipunctata did not differ in the choice and no-choice tests. Larval development was prolonged by one day on D. citri compared to R. maidis nymphs but did not differ between either of these diets and E. kuehniella. Larval survival to adult averaged 93–100% and was not impacted by diet. Adult life span did not differ between diets although those on D. citri and R. maidis nymphs weighed less and produced fewer but more fertile eggs than on E. kuehniella eggs. Significant reduction of D. citri nymphs averaging 54% was observed in colonies caged with adult A. bipunctata on field planted citrus. R° (net reproductive rate) was least for beetles fed R. maidis, but otherwise there were no significant differences in demographic parameters. Successful feeding, development and reproductive performance of A. bipunctata suggest its usefulness as biological control agent of D. citri as well as aphid species exemplified by R. maidis.

Effect of Horticultural Mineral Oil on Huanglongbing Transmission by Diaphorina citri Kuwayama (Hemiptera: Psyllidae) Population in a Commercial Citrus Orchard in Sarawak, Malaysia, Northern Borneo

“…Undoubtedly, ACP was answerable for the fast dissemination of HLB among trees over time inside the citrus grove. Application of selective insecticides [ 34 , 35 , 36 , 37 ] to rotate with petroleum oil sprays and to be supplemented by biological control agents such as Tamarixia radiata (Waterston) and Diaphorencyrtus aligarhensis (Shafee, Alam and Argarwal) as well as several ladybeetle species and Argentine ant Linepithema humile are advocated for development of an integrated pest and disease management strategy of D. citri [ 33 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. This will definitely discourage and impede HLB disease transmission through rapid suffocation and prolonged insects’ injury process.…”

“…However, it is unlikely to provide complete prevention of CLas spread if control of D. citri population is by natural enemies alone [32,33]. Application of selective insecticides [34][35][36][37] to be supplemented by biological control agents such as Tamarixia radiata (Waterston) (Hymenoptera: Eupholidae) and Diaphorencyrtus aligarhensis (Shafee, Alam and Argarwal) (Hymenoptera: Encyrtidae) as well as several ladybeetle species and Argentine ant Linepithema humile (Hymenoptera: Formicidae) are recommended for development of integrated pest and disease management strategy of D. citri [38][39][40][41][42][43][44][45]. There is usually no treatment for HLB and the best curative method is to carry out the integrated disease management utilizing planting materials that are healthy and Polymerase Chain Reaction (PCR) certified HLB-free, elimination of symptomatic citrus trees to reduce inoculum sources, monitoring of vector and disease incidence and insecticidal applications [6][7][8], as to reduce the spread of the HLB disease.…”

Effectiveness of the Brown Lacewing, Sympherobius barberi Banks as a Biological Control Agent of the Asian Citrus Psyllid Diaphorina citri Kuwayama

“…The larval development prolonged on the diet of D. citri nymphs compared to E. kuehniella eggs. The Ephestia eggs is a typical diet used for commercial rearing of several predators, which support maximum survival in most cases ( Qureshi and Stansly, 2011 ; Khan et al, 2016 ), whereas D. citri was a new prey for the S. barberi. The presence of wing buds in the late instars nymphs of D. citri may have caused some deterrence for the S. barberi larvae and reduced the consumable body contents resulting in predator spending more time and energy in handling nymphs thus prolonged development and reduced survival in some cases.…”

Diaphorin, a polyketide synthesized by an intracellular symbiont of the Asian citrus psyllid, is potentially harmful for biological control agents

“…In addition to vertebrates, D . citri has natural enemies from various lineages, including arthropod predators (e.g., lady beetles, lacewings, and spiders) [3,4,7], hymenopteran parasitoids [2,8], and entomopathogenic fungi [5,6]. As these arthropods and fungi are potentially useful biological pesticides, information regarding their susceptibility to diaphorin is essential for the successful biological control of D .…”