Boron deficiency mediates plant–insect (Diaphorima citri) interaction by disturbing leaf volatile organic compounds and cell wall functions.

This article investigates the impact of boron deficiency (Bd) on the feeding behavior of the Asian citrus psyllid (ACP; Diaphorina citri Kuwayama), the primary vector of Huanglongbing (HLB), a destructive citrus disease. Using hydroponic culture of navel orange plants, the study found that Bd increased the release of volatile organic compounds (VOCs), particularly methyl salicylate (MeSA), by upregulating the shikimic acid metabolic pathway, which enhanced ACP attraction. Additionally, Bd weakened the mechanical properties of leaf cell walls by decreasing boron content and altering pectin and cellulose composition, facilitating easier stylet penetration and increased phloem ingestion by ACP, as evidenced by electrical penetration graph (EPG) recordings. These findings suggest that boron deficiency in citrus plants promotes ACP feeding activity, potentially accelerating HLB spread, highlighting the importance of plant nutrition in managing vector-host interactions.