Seed Dormancy Mechanisms and Germination Ecology of Ridolfia segetum as an Invasive Weed in Cereal Fields

Abstract

Seed dormancy mechanisms and germination ecology of Ridolfia segetum were investigated to understand its invasive potential and persistence in cereal-based agroecosystems. Laboratory and field experiments were conducted to evaluate the effects of temperature, moisture, light conditions, and burial depth on dormancy release and germination behavior. Results indicated that freshly matured seeds exhibited strong primary dormancy, requiring specific environmental cues for germination. Cold stratification and alternating temperature regimes significantly enhanced germination, suggesting that seasonal temperature fluctuations play a key role in dormancy alleviation. Light exposure positively influenced germination of surface-sown seeds, whereas seeds buried at greater depths showed reduced emergence due to limited light penetration and altered microenvironmental conditions. Moisture availability was a critical factor regulating germination, with optimal germination observed under adequate soil moisture, while drought conditions strongly inhibited seedling emergence. Burial depth experiments revealed highest emergence from shallow soil layers, while deeper seeds remained viable but dormant, contributing to long-term seedbank persistence. Seasonal field observations demonstrated synchronized germination during autumn and early winter, coinciding with cereal crop establishment stages. The species exhibited a persistent seedbank strategy, enabling survival under repeated soil disturbance and crop rotation systems. Environmental variability, particularly rainfall distribution and temperature fluctuations, significantly influenced emergence timing and cohort formation. The adaptive dormancy and germination traits of R. segetum facilitate its successful establishment and competitiveness in cereal fields.