I. Overview of Occurrence
The green plant bug, from the order Hemiptera and family Miridae, primarily damages spring Tea and is widespread in northern tea regions. In spring, nymphs of the green plant bug damage tea buds, affecting both the yield and quality of tea. Severely affected tea gardens can see a 70% or greater reduction in their Spring Tea harvest. After the first generation of adults emerge, they leave the tea gardens as surrounding preferred food crops increase; in autumn, as these crops decrease, they return to the tea gardens to overwinter. Generally, mid-September to early October is when large numbers of adult green plant bugs migrate back to the tea gardens, with this migration period lasting about 20 days. Precise control during the migration period of the green plant bug can significantly reduce damage the following year, with control efficacy exceeding 90%, and it ensures the safety and quality of the next year's spring tea.
II. Control Threshold
When the number of green plant bugs trapped by the traps reaches 4-5 per 5 days, autumn control measures should be implemented in the Tea Garden.
III. Control Techniques
When the population of green plant bugs in the tea garden reaches the control threshold, the first application of pesticide should commence, followed by subsequent applications every 7 days, for a total of three applications. When spraying, ensure that the internal parts of the tea bushes are thoroughly covered, and also spray the protective forests and weeds around the tea garden.
For green and non-polluting tea gardens, insecticides such as bifenthrin, indoxacarb, and chlorantraniliprole are recommended. For organic tea gardens, botanical insecticides like matrine, veratrine, and pyrethrum are suggested.
IV. Precautions
1. To effectively achieve the goal of controlling green plant bugs, it is recommended that tea regions implement unified control measures.
2. To ensure even application of pesticides, it is suggested to use high-pressure motorized sprayers for control.
Sunshine Coast Academy of Agricultural Sciences Tea Research Institute
National Tea Industry Technology System – Rizhao Comprehensive Test Station