Seyedahmad Kalantarahmadi; Jahanfar Daneshian; Habib Mobinirad
Abstract
In order to develop winter cultivation and improve crop rotation in the region, an experiment has been conducted to evaluate the effects of sowing date on sunflower cultivars seed yield. It is a split-plot based on completed randomized blocks design with four replications in Safiabad Agricultural and ...
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In order to develop winter cultivation and improve crop rotation in the region, an experiment has been conducted to evaluate the effects of sowing date on sunflower cultivars seed yield. It is a split-plot based on completed randomized blocks design with four replications in Safiabad Agricultural and Natural Resources Research and Education Center of Dezful and has taken place during two years (2015-2016). The main plots are consisted of four sowing date levels (23rd Jan, 6th Feb, 20th Feb, and 6th Mar), while the sub plots include nine levels of cultivars (Azargol, Armavirski, Barzegar, Progress, Record, Shams, Farokh, Ghasem, and Gabor). Delay in the sowing date has decreased growth period length and plant height, with the greatest number of seeds per capitulum (684.17) belonging to record cultivar on the first sowing date in the first year and the maximum one (767.47) occurring again to this cultivar on the third sowing date in the second year. The maximum seed yield in the first (3850 kg.ha-1) and second (4088 kg.ha-1) year belong to the first sowing date (23rd Jan) and Azargol cultivar. Based on the results, Azargol cultivar have had the lowest rank, being considered as the cultivar with the highest seed yield on all sowing dates, followed by Record and Armavirski, in the second and third placed, respectively. In terms of stability, considering that Farrokh cultivar also has had the lowest standard deviation, it has been selected as the most stable cultivar.
Hosna Fayazi; Ebrahim Zeinali; Afshin Soltani; Benyamin Torabi
Abstract
Global climate change is among the most important agricultural and food security challenges. This study tries to investigate the effect of climate change on potential yield and water productivity of forage maize (Zea mays L.) in Iran. Two scenarios of RCP4.5 and RCP8.5 are used to predict the future ...
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Global climate change is among the most important agricultural and food security challenges. This study tries to investigate the effect of climate change on potential yield and water productivity of forage maize (Zea mays L.) in Iran. Two scenarios of RCP4.5 and RCP8.5 are used to predict the future climate (2050s) and climate data of 2001-2015 have been used as the base period. Potential yield is estimated using SSM-iCrop2 model according to the GYGA protocol and the climate changes for both scenarios are applied in the model. The results show that the climate change will not have a considerable effect on forage maize yield compared to the current conditions (85.6 ton ha-1) and will only lead to an increase of 0.9% and 1.6% in on both scenarios, respectively. This may be attributed to maize being a C4 plant and thus non-effectiveness of CO2 increase on its growth. Also, the temperature will remain in optimum range for maize in most of the main regions for forage maize cultivation areas in Iran. Water productivity in both scenarios will increase by 0.4% and 1.6%, compared to current conditions (10.4 kg m-3), respectively, which may be due to increased CO2 concentration and more closure of stomata. Also, improved water productivity in forage maize may be attributed to increase yield potential due to the fact that no considerable changes are observed in terms of the required water, evapotranspiration and irrigation times.
mohsen zafaranieh; arman Azari
Abstract
The present study tries to quantify germination response of Guar (Cyamopsis tetragonoloba) to temperature and water potential. Performed in Vali-e-Asr University laboratory in 2020, it is a completely randomized design in a factorial arrangement with four replications. It aims at quantifying the rate ...
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The present study tries to quantify germination response of Guar (Cyamopsis tetragonoloba) to temperature and water potential. Performed in Vali-e-Asr University laboratory in 2020, it is a completely randomized design in a factorial arrangement with four replications. It aims at quantifying the rate of Guar germination in response to temperature, and water potential. The seeds have been germinated at seven temperatures (5, 10, 15, 20, 25, 30, and 35°C) and six water potentials (0, -0.2, -0.4, -0.6, -0.8, and -1 MPa). The results reveal that the Beta function is suitable for describing the response of seed germination temperature, and water potential. Under different water potentials, base, optimum, and maximum temperatures have been 7.3-12°C, 22.1-25.8°C, and 32.2-36°C, respectively. The hydrothermal time parameters are 268.3 bar °C h, -1.103 MPa and, 8.36°C for ɵHT (hydrothermal time constant). The data obtained from these models can be used to establish and manage guar for cultivation in different areas.
Alireza Nehbandani; Mojtaba Saadati; Mahdi Goodarzi; Afshin Soltani
Abstract
Food security reduction due to climate change is one of the most important challenges in the 21st century. This study was carried out to predict the potential yield and production of the country’s strategic crops examining various climate change scenarios. In this study, the potential yield & ...
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Food security reduction due to climate change is one of the most important challenges in the 21st century. This study was carried out to predict the potential yield and production of the country’s strategic crops examining various climate change scenarios. In this study, the potential yield & production of 17 crops (Wheat, barley, rice, common bean, rapeseed, chickpea, grain maize, cotton, lentil, potato, sesame, soybean, sugar beet, sugarcane, sunflower, alfalfa and Silage maize) were estimated under current conditions (period 2005-2014) & two climatic scenarios (optimistic:1.5 ° C increase in temperature with 14% increase in precipitation period 2005-2014; pessimistic: 1.5 ° C increase in temperature & 14% decrease in precipitation period 2005-2014) applying SSM-iCrop2 model. The results showed that the pessimistic scenario reduced the potential production of wheat & legumes (about 1%) & the optimistic scenario increased the potential production of these crops (4 & 2%, respectively). Both climate change scenarios reduced the potential production of rice, potato, oilseeds & sugar crops (4, 10, 5 & 7%, respectively). Furthermore, the potential production of Silage maize increased in both climate change scenarios (2% & 3%, respectively). The results showed that the major factors which alter crop yield could be the growing season duration, radiation use efficiency and transpiration efficiency. In general, wheat, barley, potato, and sugarcane were more affected by climate change than other crops.
Morteza Gorzin; Farshid Ghaderi-Far; Seyed Esmaeil Razavi
Abstract
In order to investigate effects of different fungicide spraying treatments on soybean seed quality, a split plot experiment was conducted in a randomized complete block design with three replications in research field of Gorgan University of Agricultural Science and Natural Resources in 2016. Two spring ...
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In order to investigate effects of different fungicide spraying treatments on soybean seed quality, a split plot experiment was conducted in a randomized complete block design with three replications in research field of Gorgan University of Agricultural Science and Natural Resources in 2016. Two spring (May 28) and summer (July 10) planting dates performed at main plots and fungicides spraying including benomyl, mancozeb, propiconazole, methyl thiophanate, carbendazim and control in two stages R3 and R6 were done in sub plots. Germination, accelerated aging, electrical conductivity, and seed health tests were used to evaluate the quality of seeds. Two fungi Alternaria sp. and Fusarium sp. spread were observed in seed lots, but lower prevalence for Fusarium sp.. Therefore, seed health was most affected by Alternaria sp.. The percentage of healthy seeds in spring sowing date was 21.48% higher than summer sowing date. All used fungicides (especially propiconazole and methyl thiophanate) significantly increased the health, germination, and vigor of seeds compared to control. The produced seeds in summer planting despite of more fungal infection, had higher seed germination and vigor than seeds of spring crops, because of exposing the seed development stages (R5-R8) to low temperatures. In the fact that, air temperature during seed development stages was more important in determining seed germination and vigor compared to pathogens. Therefore, in order to achieve high seed quality, it is appropriate to use summer planting with the utility of suitable fungicides such as propiconazole and methyl thiophanate at R3 and R6 growth stages.