Bahman Ahmadvand; Seyed Amir Moosavi; Seyed Ata Siadat; Reza Tavakkol Afshari; Ali GHATEI
Abstract
The aim of this study was to investigate the relationship between the morphometric characteristics of the seeds of different buckwheat (Fagopyrum esculentum Möench) lots obtained from different planting dates (29th Aug: 1, 13th Sep: 2, 28th Sep: 3 and 12th Oc: 4) with its seed germination quality ...
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The aim of this study was to investigate the relationship between the morphometric characteristics of the seeds of different buckwheat (Fagopyrum esculentum Möench) lots obtained from different planting dates (29th Aug: 1, 13th Sep: 2, 28th Sep: 3 and 12th Oc: 4) with its seed germination quality under different temperature treatments. For each of seed lot, four separate experiments with 11 temperature levels including 4, 7, 10, 15, 20, 25, 30, 35, 37, 40 and 45 °C were carried out in a completely randomized design with 3 replications in seed science and technology laboratory of Agricultural Sciences and Natural Resources of Khuzestan University in 2022. The results of analysis of variance demonstrated that temperature has a significant effect at the level of 1% on germination rate index. According to the model parameters and of course the standard error, the segmented model was chosen as the best model. Based on this, according to the superior (segmented) model, the base, optimal and ceiling temperatures for lot 1 are 4.82, 34.24 and 44.82 degrees Celsius respectively, in lot 2 they are 4.18, 33.82 and 46 respectively. 44.0 degrees Celsius, in lot 3 it was estimated 5, 34.64 and 43.87 degrees Celsius respectively and in lot 4 it was estimated 5, 31.69 and 44.27 degrees Celsius respectively. Identify the cardinal temperatures can be of great help in managing the optimal sowing date of crops.
Abbas Hashemi; F. Sharifzadeh; Reza Maali Amiri; Reza Tavakkol Afshari
Abstract
Safflower (Carthamus tinctorius L.) is an important industrial plant, which classified in the category of oil plants. The tolerance of plants to drought is different, as well as Plants have different temperature and water requirements, and understanding this requirement helps them survive and reproduce. ...
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Safflower (Carthamus tinctorius L.) is an important industrial plant, which classified in the category of oil plants. The tolerance of plants to drought is different, as well as Plants have different temperature and water requirements, and understanding this requirement helps them survive and reproduce. Therefore, the purpose of this study was to evaluate the germination characteristics of safflower seeds at different temperatures and humidity and the adaptation power of this plant under these conditions. For this purpose, germination of safflower seed (Faraman cultivar) was investigated in incubator at constant temperatures of 5, 10, 15, 20, 25, 30, 35 and 40 ° C. in this study, 3 regression model including, Beta model, Dent like model and segmented model were used to determine cardinal safflower temperatures. Then, to investigate germination and seedling growth response of Carthamus tinctorius toward different levels of Water Deficite Stress at an optimum temperature, another test was conducted. in this experiment, seed germination was assessed in six levels of Water Deficite Stress with the osmotic potential of 0, -3, - 5, -7 and -9 bar (in temperatures of 20 ° C). Based on Beta model, Dent like model and segmented model, the cardinal temperatures of Carthamus tinctorius seeds germination including, (Tbase, Topt and Tmax) were: (4.6, 4.1, 4.1), (22.02, 20 – 24.3, 22.5) and (43.3, 50.3, 50.3) °C, respectively.
Batool Mahdavi
Abstract
This study was conducted to study germination two species of vetch (Vicia sativa; Vicia pannonica) under temperatures (5, 10, 15, 20, 25, and 30 °C) and different water potentials (0, -2, -4, -6, -8 and -10 bar) at the Vali Asr Rafsanjan University laboratory in completely randomized design ...
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This study was conducted to study germination two species of vetch (Vicia sativa; Vicia pannonica) under temperatures (5, 10, 15, 20, 25, and 30 °C) and different water potentials (0, -2, -4, -6, -8 and -10 bar) at the Vali Asr Rafsanjan University laboratory in completely randomized design arranged as a factorial with four replications. The segmented function was evaluated to describe the relationship between germination rate and temperature. Results showed base temperature for germination of Vicia pannonica was -3.65 to 1.39, optimum temperature 23.99 to 25.57 and ceiling temperature 30 to 58.54 under different water potentials. The biological hours for germination of this specie were 32.29 to 74.97 hours under different water potentials. Also, base temperature for germination of Vicia sativa was -3.54 to 1.39, optimum temperature 22.70 to 25.64 and ceiling temperature 30 to 42.28 under different water potentials. The biological hour requirements for germination of this specie were between 33.10 to 83.54 hours under different water potentials. The results of germination rate in both species showed that with increasing water potential, germination rate decreased. In all of water potentials germination rate increased to 25°C and then decrease. Estimated parameters and the relations can be used to prediction time to germination or emergence in two species of vetch under different water potentials.
shiva barooti; reza tavakkol afshari; naser majnon hoseini; abbas hashemi
Abstract
To determine the specific temperature of Medicinal Cannabis sativa, the effects of different temperatures on germination, in a laboratory study in a completely randomized design with three replications were studied. Germination response assessment at constant temperatures (3, 5, 10, 15, 20, 25, 30, 35, ...
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To determine the specific temperature of Medicinal Cannabis sativa, the effects of different temperatures on germination, in a laboratory study in a completely randomized design with three replications were studied. Germination response assessment at constant temperatures (3, 5, 10, 15, 20, 25, 30, 35, 40 and 45ºC) was conducted. The germinated seeds were counted every day and the rate of germination percentage, cumulative germination and cardinal temperatures diagram of Cannabis sativa seed germination based on 3 regression model including segmented model, Beta model and Dent like model. The results showed that the temperature increase of 3 to 25°C significantly increases the germination rate, while the germination rate did not differ at 25 to 40°C. Also with increasing temperature over 25°C, germination was reduced. Dent like model such as higher accuracy in determining the cardinal temperatures hemp seed germination was compared with other models, Base, optimum and maximum temperature of seed germination of Cannabis sativa based on Dent like model was determined 1, 26-39.3 and 48°C respectively.
A. Hashemi; Sh. Barooti; R. Tavakkol Afshari
Volume 5, Issue 2 , January 2016, , Pages 77-84
Abstract
In order to estimate the germination cardinal temperatures, a laboratory experiment was conducted with Chrysanthemum maximum Ramond in a completely randomized design with four replications. Various constant temperatures (5, 10, 15, 20, 25, 30 and 35ºC) were considered. Germinated seeds were counted ...
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In order to estimate the germination cardinal temperatures, a laboratory experiment was conducted with Chrysanthemum maximum Ramond in a completely randomized design with four replications. Various constant temperatures (5, 10, 15, 20, 25, 30 and 35ºC) were considered. Germinated seeds were counted each day and the rate of germination and germination percentage was calculated. Cardinal temperatures diagram of Chrysanthemum maximum Ramond seed germination was constructed based on two regression models including segmented model and beta model. The effects of temperatures on rate and percentage of germination were significant. The highest germination rate was in 20º, R50=0.067 (Reverse time to 50% germination). Based on the two regression models, Intersected-lines Model and Quadratic Polynomial Model, the cardinal temperatures of Chrysanthemum maximum Ramond seeds germination (Tbase, Topt and Tmax) were: (1 - 3), (19– 23.1) and (43 – 59) °C, respectively. With increasing temperature, the more suitable conditions in terms of temperature, is created for Chrysanthemum maximum Ramond germination and germination rate is increased
Volume 3, Issue 2 , December 2014, , Pages 189-200
Abstract
In order to evaluate cardinal temperatures of milk thistle (Silybum marianum)germination an experiment was carried out in the laboratory of Plant Production College, Gorgan University Agricultural Science and natural resources. Seven temperatures in a completelyrandomized design with four replications ...
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In order to evaluate cardinal temperatures of milk thistle (Silybum marianum)germination an experiment was carried out in the laboratory of Plant Production College, Gorgan University Agricultural Science and natural resources. Seven temperatures in a completelyrandomized design with four replications was used. Temperatures were 5 to 35ºC by 5ºC intervals. The seeds with 2 mm radicles were counted as germinated seeds.The germination rate percentage and cumulative seed germination percentage were calculated for each given temperatures.Cardinal temperatures (T-base, T-optimum and T-ceiling), also, were estimated using eight non linear regression models. The effect of temperature on total germination percentage, time to 50% germination (D50) and germination rate based on 1/D50 and mean germination time inverse (1/MGT) was significant at 1% of probability level. Results indicated that by increasing temperature up to 15ºC germination increased and after that declined. Based on the highest R² and the lowest MAE and RMSE segmented model was determined as the superior model. Thus, Tb, To and Tc for D50 (time to %50 germination) were estimated as 2.75, 31.51 and 38 using segmented model.To calculate germinationrate 1/D50 index was better than 1/MGT due to higher regression coefficient and less RMSE.
