نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانش آموخته دکتری علوم علفهای هرز، گروه زراعت و اصلاح نباتات دانشکده کشاورزی دانشگاه تهران
2 استاد گروه زراعت و اصلاح نباتات دانشکده کشاورزی دانشگاه تهران
3 دانشیار گروه زراعت و اصلاح نباتات دانشکده کشاورزی دانشگاه تهران
4 هیات علمی مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی گیلان
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
This research was carried out to estimate the cardinal temperatures of Ambrosia psilostachya seed germination and evaluation of some nonlinear regression models. The experiment was performed at Weed laboratory of Tehran University in 2022. In this experiment, the seeds were exposed to 8 temperature treatments (5, 10, 15, 20, 25, 30, 35, and 40ºC) with 3 replications in a completely randomized design. The germination rate, percentage of seed germination and mean germination time of seeds were measured. Cardinal temperatures of seed germination were estimated by using four regression models including segmented, dent-like and beta (four and five parameters) models. The performance of models and statistical indices was compared by RMSE (root mean squared of error), R2 (coefficient of determination) and AICc (corrected Akaike Information Criterion). Highest germination percentage was obtained at 15, 20 and 25°C with 60.3%, 63.7% and 63%, respectively. highest germination rate (0.13d-1) and the lowest mean germination time (7.48d) were related at 25°C. Largely due to their lower AICc and RMSE, the beta model (five parameters) was found to be the best model for predicting the response of germination percentage to temperature in A psilostachya. Generally, base, optimal and ceiling temperatures were estimated 5, 25.5 and 42.13°C respectively for beta five-parameters model.
کلیدواژهها [English]