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Abstract The occurrence and damage of Xylotrechus quadripes Chevr were investigated in different time points and micro environments in Simao south island river coffee test demonstration ñeld. The results showed that X. quadripes mainly damaged 5-year-old coffee trees. X. quadripes occurred one generation per year in Simao region, and the larval stage lasted 296 -322 d. The adult could be found in four seasons because of different development progress and overlapping generations. In different micro environments, X. quadripes were mainly distributed in mixed forests and the coffee land in sunny slope. The adult enjoyed sunshine on the coffee trees at noon. The natural enemy Prislauacus nigripea kieff was found to parasitize in the larvae of X. quadripes, which could control the population of X. quadripes.
Key words Arabica coffee; Xylotrechus quadripes Chevr; Occurrence; Damage regularity; Natural enemies; Prislauacus nigripea Kieff
Xylotrechus quadripes Chevr, belonging to Cerambyeinae, Cerambyeidae, Coleoptern, is an important insect pest damaging coffee tree. The larvae of X. quadripes damage the trunk of coffee tree; it eats epidermis in the initial stage, then drills into xylem and bores coffee trunk into crisscross tunnels, resulting in weak tree vigor, yellow leaves, or even death under severe condition. The damage of X. quadripes seriously restricts the development of coffee planting industry, so prevention and control of X. quadripes has attracted much concern and attention. Pu ' er City of Yunnan Province has become one of the major coffee producing areas with the largest planting area, highest output and the optimal quality. Pu'er City locates in subtropical regions, due to industrialization and large-scale planting of coffee tree started in 1988, the harm of X. quadripes seriously threats the development of coffee planting industry[1]. X. quadripes and Dihammus cervinas Bates are important borers of coffee tree, and mainly feed stem xylem of plants[z]. Survey results demonstrate that X. quadripes causes severe damage; in coffee area with norm management and timely prevention and control, the damage rate is lower than 5% ; in old coffee garden with no prevention and control measures the damage rate is above 30%. X. quadripes becomes an important factor restricting and threatening the development of coffee industry. With coffee trees planted in Simao coffee demonstration field as the test materials ,...