نوع مقاله : مقاله پژوهشی
نویسندگان
دانشکده کشاورزی و منابع طبیعی دانشگاه تهران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Understanding and predicting the emergence of winter wild oat (Avena ludoviciana) under changing climate conditions is vital for effective management, yet the combined effects of burial duration and soil moisture on its environmentally driven seed dormancy and germination remain poorly quantified in arid and semi-arid regions. This study examined the effects of soil moisture during seed burial on dormancy release and germination dynamics of A. ludoviciana.
Method: A factorial experiment in a randomized complete block design with three replications was conducted over two consecutive cropping seasons (2021–2023). Treatments included seed type (intact with hull vs. dehulled), burial duration (1-5 months), and five soil water potentials (0 to −0.8 MPa). Seeds were incubated under controlled temperatures reflecting historical soil conditions, and germination was evaluated at six incubation temperatures (5–30°C). Fractional cumulative germination was modeled using a modified Triangle Area Model (TAM) that incorporates the combined effects of burial duration, soil temperature, and moisture.
The results showed that burial duration had the greatest influence on germination, followed by soil water potential and temperature. Dehulled seeds germinated more rapidly than intact seeds, indicating the regulatory role of the hull. Maximum germination (~85%) occurred at −0.3 MPa and 15°C, whereas severe drought ((−0.8 MPa) reduced germination, suggesting a mechanism for dormancy maintenance under unfavorable conditions. The modified TAM accurately simulated germination dynamics across treatments, achieving an R² of 0.88 and an RMSE of 0.01. Prolonged burial under sufficient moisture progressively reduced dormancy, reflecting interactions between physical and physiological dormancy.
کلیدواژهها [English]
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