The control effect of bionic sticky traps on Apolygus lucorum in pear orchards in Taigu District

【Objective】Apolygus lucorum is a major polyphagous pest in pear orchards, causing severe damage to young fruits and reducing their commercial value. Since the 2000s, its occurrence and damage have progressively intensified, as the last-generation adults in late October lay eggs for overwintering, directly influencing the population density of the subsequent year. Critically, September- October coincides with the ripening period of pear in northern pear areas, and chemical control is constrained by pesticide residue concerns—creating an urgent demand for green physical control measures. Traditional sticky traps suffer from poor selectivity and high non-target mortality of natural enemies, which disrupts the orchard ecological balance. Based on the aposematism principle, a novel bionic striped sticky trap was developed to warn natural enemies and minimize non-target trapping. This study aimed to clarify the population dynamics of A. lucorum, evaluate the trapping efficacy and ecological safety of striped traps, optimize their deployment parameters, and assess the trapping effect on female adults when combined with sex pheromone lures, thereby providing a scientific and practical green control strategy. 【Methods】The experiments were conducted in Yuluxiang (Pyrus bretschneideri) pear orchard (37°20′ N, 112°29′ E) in Taigu District, Jinzhong City, with an altitude of 866 m and an area of 2 hm2 . Pear trees were planted with a spacing of 4 m × 3 m, a height of 2.5-3 m, and subjected to conventional management, including chemical control applications in early April, early May, early June, mid-July, and midAugust. From April to November in 2023 and 2024, sex pheromone triangular traps were employed to monitor the population dynamics of A. lucorum (15 traps/hm2 , spaced 30 m apart, 20 m away from the field edge, and 1.5 m above the ground). Backing plates were updated every 15 days, and lures were replaced every 30 days. Trapping effects of 11 types of sticky traps (white, red, pink, yellow, green, blue, light blue, purple, gray, black, and bionic striped trap) were compared, with 6 replicates for each type; traps were randomly hung on September 22, 2024 (spaced 8-12 m apart) and retrieved after 30 days. Trapped insects were classified into natural enemies, neutral insects, and pests to calculate the natural enemy-to-pest ratio. With yellow sticky traps as the control, the effects of hanging height (1.5 m, 3.0 m) and density (1- 8 traps per tree, based on a 12 m2 projected canopy area) on striped traps were optimized—with 12 replicates for the height test and 6 replicates for the density test. Traps were hung on October 30 and retrieved after 30 days. Additionally, synergistic effects of sticky traps combined with sex pheromone lures were tested in five treatments (6 replicates each): yellow sticky trap, yellow sticky trap + lure, striped sticky trap, striped sticky trap + lure, and transparent sticky trap + lure (CK). Traps (25 cm × 30 cm, uniform viscosity) were hung 1.5 m above the ground on September 24, 2025 (spaced 30 m apart between treatments), with lures fixed at the center using iron wire. After 30 days, the total trapping amount, number of male and female adults, and female proportion were recorded. Data were organized using Microsoft Excel 2016 and analyzed via one-way ANOVA, independent sample t-test, and Duncan’s new multiple range test with IBM SPSS 27.0 (P＜0.05).【Results】Results indicated that A. lucorum exhibited three annual population peaks (mid- June, mid- September, late October) in both 2023 and 2024. Notably, the population density of the last-generation adults in late October reached the highest (83.33 adults · 666.7 m- 2 in 2023 and 116.00 adults · 666.7 m- 2 in 2024), with total trapping amounts of 1305 and 1642 adults, respectively, demonstrating an increasing trend. Furthermore, striped sticky traps (15.83 adults per trap) and yellow sticky traps (13.67 adults per trap) demonstrated significantly higher trapping efficacy compared to other colored traps (P＜0.05), while red traps showed the lowest efficacy (2.33 adults per trap). Among all tested traps, the blue sticky trap exhibited the highest natural enemy-to-pest ratio (0.734), with an average of 19.33 natural enemies trapped per trap (90% of which belonged to Syrphidae), whereas the striped sticky trap had the lowest ratio (0.025), with only 1.83 natural enemies trapped per trap. Notably, the non-target mortality of Propylaea japonica caused by striped sticky traps was 0.21 times that of yellow sticky traps. Regarding the factors affecting trapping efficiency, density (rather than height) had a significant impact (P＜0.05): hanging 4 striped traps per tree (48.50 adults· 12 m- 2 ) yielded a trapping amount comparable to that of hanging 6 yellow traps per tree, and the striped sticky trap exhibited significantly higher efficacy at a density of 2-4 traps per tree (P＜0.05). A significant synergistic trapping effect was observed when used in combination with sex pheromone lures: the combination of striped sticky traps and lures captured 1.23 times as many adults and 3.5 times as many female adults, respectively, compared to using the lures alone.【Conclusion】The bionic striped sticky trap demonstrates superior comprehensive performance in terms of trapping efficacy, ecological safety, and cost-effectiveness. When combined with sex pheromone lures, it establishes a synergistic model of“long- distance chemical attraction + short- distance visual capture”, which enhances the trapping efficiency of female A. lucorum. Therefore, it is recommended to employ striped traps at a density of 1500 traps · hm- 2 during the three population peaks (especially late October) at a height of 1.5-3.0 m, prioritizing the“striped trap + sex pheromone lure”combination. This study offers a practical green control strategy for A. lucorum in pear orchards and provides a reference for the management of similar pests.