Taiwan tea leafhopper

Taxonomic position: Jacobiasca formosana, formerly known as Empoasca formosana, belongs to the order Hemiptera and the family Cicadellidae. It is recognized as a significant pest of tea plants, particularly in subtropical tea-growing regions where it causes substantial reduction in both yield and the quality of tea leaves.

Host plants: The primary host of the Taiwan tea leafhopper is the tea plant (Camellia sinensis). The insect preferentially feeds on the tender apical buds and young leaves. While it has been observed on some secondary hosts, its economic impact is almost exclusively linked to the tea industry.

Biology and life cycle: The life cycle consists of the egg, five nymphal instars, and the adult stage. The female lays eggs inside the tender plant tissue. Due to the rapid development cycle enabled by warm climate conditions, the insect can produce many overlapping generations per year, leading to severe outbreaks if left unchecked by natural predators or human intervention.

Damage characteristics and economic impact: Both nymphs and adults feed by piercing the plant cells and sucking the sap. The injection of toxic saliva into the leaves causes the characteristic curling and browning of leaf edges, a condition often referred to as leaf scorching. This damage impairs the photosynthesis process and forces the plant to divert energy, resulting in stunted growth and drastically reduced harvest quality.

Control measures: Management of this pest requires a strategic approach to maintain plantation health:

• Utilizing biological control agents such as parasitic wasps and predatory bugs.
• Implementing regular pruning practices to disrupt the life cycle of the leafhopper.
• Monitoring the population density using yellow sticky traps to time chemical interventions.
• Application of environmentally responsible insecticides during peak emergence periods to minimize chemical residue on the tea leaves.