Phenology and Overwintering Biology of Halyomorpha halys (Hemiptera: Pentatomidae) in Fruit Orchards

Abstract

Phenological progression and overwintering biology of Halyomorpha halys (Hemiptera: Pentatomidae) were investigated in fruit orchard ecosystems to understand seasonal population dynamics and survival strategies under field conditions. Field monitoring was conducted across orchard habitats to record life stage distribution, developmental timing, and seasonal abundance patterns in relation to temperature and host availability. Distinct population peaks were observed during late spring and summer, corresponding to active feeding and reproductive phases on fruit hosts, while a marked decline in activity occurred during late autumn as adults-initiated aggregation and migration to protected overwintering sites. Overwintering behavior was primarily associated with sheltered microhabitats such as leaf litter, bark crevices, and human-made structures adjacent to orchards. Survival during overwintering was strongly influenced by minimum temperature thresholds and microclimatic stability, with higher mortality recorded in exposed conditions. Degree-day accumulation models effectively described developmental progression from nymphal instars to adult emergence, highlighting temperature-dependent phenology. The synchronization of life cycle events with orchard phenology emphasized the pest’s adaptability to perennial fruit production systems. Early-season colonization of orchards following overwintering emergence underscored its potential for rapid population buildup and subsequent fruit damage. The findings provide critical insights into seasonal movement patterns and survival mechanisms, supporting the development of phenology-based monitoring and targeted management strategies to reduce pest pressure in fruit orchard agroecosystems.