Fungus Suppresses Asian Citrus Psyllids

Dan Citrus, Huanglongbing (HLB)/Citrus Greening, Research

Ento Curtec sprayer applying fungal mixture in grove

The citrus disease HLB, also known as citrus greening, has a formidable enemy in a fungal pathogen, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers reported. The fungus is Cordyceps javanica, strain Apopka, discovered by research scientist Lance Osborne in the mid-1980s. The fungus was isolated from dead insects on plants in a greenhouse at the UF/IFAS Mid-Florida Research and Education Center in Apopka.

Spores of Cordyceps javanica grow in bead-like strands across citrus leaves, attaching themselves to the body of HLB-spreading Asian citrus psyllids (ACP). They germinate and infect the psyllids, effectively lowering pest numbers by up to 90%. The fungus sustains itself and its impact on the psyllids for two full weeks after its application.

Scientists at two UF/IFAS research centers published their Cordyceps javanica findings in the Sept. 14 issue of Insects.

Pasco Avery

“Growers must control the psyllid to produce fresh fruit,” said Pasco Avery, a UF/IFAS Indian River Research and Education Center scientist in Fort Pierce. “What the growers need is an integrated pest management program to mitigate the psyllid populations, minimize the input of non-selective insecticides, and preserve the lady beetles, lacewings and parasitic wasps that are the psyllid’s natural enemies.”

Avery said the psyllid develops resistance to synthetic broad-spectrum chemical insecticides. Therefore, an integrative pest management program is needed. Scientists can employ a combination of tools such as the fungus C. javanica, along with the psyllid’s natural enemies, to protect citrus trees.

To measure the effectiveness of the fungus, Avery employed a tap-sampling method to collect psyllids present on citrus trees before and after the fungus was applied.

Avery and his colleagues mixed a powder form of the fungal product with water and white oil and …..

Learn more about the research on how Fungus Suppresses Asian Citrus Psyllids on Citrus Industry website.