Review paper
Huanglongbing (HLB) and its vectors: recent research advances and future challenges
Pérez-Hedo, Meritxell; Hoddle, Mark S.; Alferez, Fernando; Tena, Alejandro; Wade, Tara; Chakravarty, Shourish; Wang, Nian; Stelinski, Lukasz L.; Urbaneja, Alberto
Entomologia Generalis Volume 45 Number 1 (2025), p. 17 - 35
published: Feb 26, 2025
published online: Feb 18, 2025
manuscript accepted: Jan 15, 2025
manuscript revision received: Jan 7, 2025
manuscript revision requested: Jan 3, 2025
manuscript received: Oct 16, 2024
DOI: 10.1127/entomologia/2024/3081
Open Access (paper may be downloaded free of charge)
Abstract
Huanglongbing (HLB), also known as citrus greening disease, is one of the most destructive diseases affecting the global citrus industry. It is caused by bacteria of the Candidatus Liberibacter genus, primarily C. L. asiaticus (CLas), C. L. africanus (CLaf), and C. L. americanus (CLam), transmitted by Asian citrus psyllid [Diaphorina citri (vectors CLas)] and African citrus psyllid (Trioza erytreae [CLaf]), which likely can vector all three C.L. species. HLB causes severe symptoms in citrus trees, including leaf mottling, deformed fruits, and tree decline, leading to significant economic losses and tree death in citrus-producing regions across Asia, the Americas, and Africa. Controlling HLB progression remains challenging due to the lack of effective curative treatments and the ongoing global spread of psyllid vectors. This review provides a comprehensive overview of biological and epidemiological aspects of HLB and its vectors, focusing on recent advances in understanding of the biology of the pathogen and vector-host interactions. Additionally, we explore the case of Florida (USA), one of the most adversely affected regions, where HLB has drastically impacted commercial citrus production. The review highlights recent technological and biological advances aimed at mitigating HLB’s impacts and discusses current research focused on enhancing vector control, improving plant resilience, and advancing detection methods. Finally, we address future challenges, including the need for sustainable management strategies, international cooperation, and the integration of new biotechnological tools to manage HLB-causing pathogens and disease progression, all of which are necessary to ensure the long-term sustainability of the global citrus industry.
Keywords
biological control • insecticide resistance • RNA interference (RNAi) • CRISPR genome editing • plant defense mechanisms