Seedbank Persistence and Emergence Phenology of Anagallis arvensis in Mediterranean Dryland Farming Systems

Abstract

Persistence of weed seedbanks and seasonal emergence patterns are critical ecological factors influencing weed infestation and long-term management in dryland farming systems. Field and laboratory experiments were conducted to evaluate seedbank longevity and emergence phenology of Anagallis arvensis under Mediterranean dryland conditions. Seeds were buried at different soil depths and periodically retrieved over multiple seasons to determine viability and persistence under natural environmental conditions. Concurrent field observations were performed to monitor seasonal emergence dynamics in relation to rainfall, soil temperature, and moisture availability. Results demonstrated that A. arvensis seeds maintained considerable viability within the soil seedbank, particularly when buried at deeper depths where environmental fluctuations were reduced. Seed persistence declined gradually over time due to seed decay, predation, and environmental exposure, with more rapid viability loss observed for seeds remaining near the soil surface. Emergence occurred primarily during cooler and wetter periods characteristic of Mediterranean autumn and early winter conditions. Fluctuations in rainfall and soil moisture strongly influenced germination timing and seedling establishment, resulting in distinct seasonal emergence peaks. Emergence density decreased substantially during dry and high-temperature periods, indicating sensitivity of seed germination to moisture stress. The extended emergence period and persistent seedbank contributed to the adaptive success of A. arvensis in cereal-based dryland cropping systems. Seedlings emerging early in the cropping season exhibited greater competitive ability and higher survival than later cohorts. Understanding the persistence and emergence ecology of A. arvensis is essential for improving timing and effectiveness of integrated weed management practices.