IVIA’s Biological Control Program Successfully Reduces Citrus Psyllid Populations in Cyprus

The Instituto Valenciano de Investigación Agrícola (IVIA) has made significant progress in controlling Diaphorina citri, the invasive psyllid responsible for spreading Huanglongbing (HLB) or citrus greening disease, through a targeted biological control program in Cyprus. This initiative, launched in 2024, has demonstrated measurable success in reducing psyllid populations, offering a sustainable alternative to chemical pesticides in citrus farming.

Collaboration Between IVIA and Cyprus

The program, spearheaded by IVIA in partnership with Cypriot authorities, began after the detection of Diaphorina citri in Cyprus in 2023—the first confirmed presence of the pest in the European Union. Ángel Marhuenda, director general of the Common Agricultural Policy, emphasized the importance of the collaboration during a 2024 meeting with Cypriot officials, stating that the program’s early results showed “a very significant impact on Diaphorina citri populations.”

IVIA’s approach focuses on introducing natural predators, including the parasitoid wasp Tamarixia radiata, which was brought from California. This method aligns with the institute’s expertise in sustainable pest management, as highlighted in its 2024 reports. “The integration of biological control with traditional phytosanitary measures has proven effective in reducing vector populations without relying solely on chemical interventions,” noted IVIA researchers.

Results of the Biological Control Program

Monitoring efforts conducted by IVIA, including field surveys led by professor Alberto Urbaneja, revealed a dramatic decline in Diaphorina citri populations. By October 2025, field data showed a “strong reduction in psyllid numbers” across most monitored areas, with some regions reporting over 90% parasitism rates in high-density infestation zones. The latest assessment in May 2026 confirmed that active psyllid colonies were “significantly lower” than in 2024, with only isolated adults and nymphs detected on tender shoots.

“The program’s success underscores the potential of biological control as a long-term, environmentally friendly strategy for managing citrus pests,” said Urbaneja. However, officials caution that vigilance remains critical, as residual populations could re-emerge during peak infestation periods.

Challenges and Future Outlook

Cyprus’s extensive citrus cultivation—spanning commercial orchards, private gardens, and urban areas—complicated eradication efforts. Chemical treatments alone proved insufficient, prompting the adoption of IVIA’s integrated approach. This model has since been recognized as a “strategic benchmark” for Mediterranean citrus-growing regions, according to Marhuenda.

Looking ahead, IVIA and Cypriot authorities plan to expand monitoring and continue releasing Tamarixia radiata in key agricultural zones. The program’s framework may also serve as a template for other EU countries facing similar threats from Diaphorina citri.

The initiative highlights the importance of international scientific cooperation in addressing agricultural crises. As HLB remains a global threat to citrus production, IVIA’s work in Cyprus offers a replicable model for sustainable pest management in the face of climate change and invasive species.