Biological Control of the Asian Citrus Psyllid

Dan Citrus, Huanglongbing (HLB)/Citrus Greening

Figure 1. Adult southern two-spotted ladybeetle feeding on ACP nymphs

Managing the Asian citrus psyllid (ACP) is critical because of its role in spreading huanglongbing (HLB). Biological control is one method for ACP control. It is essential for developing integrated and sustainable pest management strategies. Biological control has always been a vital component of citrus pest management in Florida; understanding its contribution to the mortality of ACP is crucial.

Despite the scientifically proven impact that biological control has on reducing ACP populations, there has been no evidence to date that it is sufficient to manage HLB in Florida. However, it contributes significantly to ACP suppression in commercial groves and other habitats where chemical control is not appropriate, such as urban settings. Studies have shown significant contributions to the mortality of ACP and other citrus pests in Florida from several biological control agents, including predators, parasitoids, and entomopathogens. 

Several predators are known to attack ACP in Florida. These include multiple species of ladybeetles, lacewings, spiders, hoverflies, and syrphid flies. Ladybeetles are one of the major groups that significantly manage ACP, with species including southern two-spotted ladybeetle, multicolored Asian ladybeetle, blood-red ladybeetle, little red ladybeetle, and metallic blue ladybeetle. Laboratory studies confirmed that the larvae of all these species developed and the adults reproduced on a diet of ACP nymphs, except the blood-red ladybeetle, which developed but did not reproduce.

University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers conducted multiple experiments in the field to determine the natural mortality in the nymphal cohorts of ACP within two years of discovering HLB in Florida. Colonies of nymphs were left exposed to natural enemies or protected with sleeve cages. Predators such as ladybeetles, lacewings, syrphid flies, and spiders were frequent visitors to the unprotected colonies and …..

Learn more about Biological Control of the Asian Citrus Psyllid on the Citrus Industry website.