Germination Ecology and Emergence Pattern of Lolium remotum as a Weed in Flax and Cereal Cropping Systems

Abstract

Germination ecology and emergence patterns of Lolium remotum were investigated to understand its adaptive behavior and persistence as a weed in flax and cereal-based cropping systems. Seed germination responses were evaluated under varying temperature regimes, light conditions, and soil moisture levels under controlled laboratory and field-simulated environments. Results indicated that L. remotum seeds exhibited broad germination tolerance across moderate temperature ranges, with highest germination under alternating temperature conditions that mimic seasonal field fluctuations. Light exposure significantly enhanced germination, indicating a positive photoblastic response and preference for shallow soil positioning. Moisture availability strongly influenced germination success, with reduced emergence observed under water-limited conditions. Field emergence studies revealed synchronized germination flushes following rainfall or irrigation events, particularly during early crop establishment stages. Seedling emergence was highest in minimally disturbed soils, indicating sensitivity to burial depth and soil inversion. The species demonstrated strong adaptation to flax and cereal agroecosystems through rapid early growth and competitive seedling establishment, allowing efficient resource capture during critical crop development phases. Dormancy mechanisms contributed to staggered emergence across the growing season, enhancing long-term persistence in the soil seedbank. Competition with crops was most severe during early vegetative stages, where rapid weed emergence reduced light and nutrient availability for crop seedlings. The study highlights the ecological flexibility of L. remotum and its ability to persist under diverse agronomic conditions. These findings emphasize the need for integrated weed management strategies targeting seedbank reduction, timely sowing, and crop competition enhancement to effectively suppress its establishment in flax and cereal production systems.