Benjamin Torabi; Najebullah Ebrahimi; Afshin Soltani; Ebrahim Zeinali
Abstract
The present study was conducted to parameterize the SSM_iCrop model and evaluate the prediction of growth and development of faba bean in Gorgan climate condition. This study was carried out on faba bean cv."Barkat" as split-plot in randomized complete block design with four replications at Gorgan University ...
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The present study was conducted to parameterize the SSM_iCrop model and evaluate the prediction of growth and development of faba bean in Gorgan climate condition. This study was carried out on faba bean cv."Barkat" as split-plot in randomized complete block design with four replications at Gorgan University of Agricultural Sciences and Natural Resources in 2015-2016. The experimental factors consisted of planting date (27 November, 25 December and 31 January) and plant density (5, 15, 25 and 35 plants/m2). The parameters of phonological stages, leaf expansion and senescence, production and distribution of dry matter and water balance were estimated using the present data experiment and other data. The results of model evaluation showed that, it can well predict, days to flowering (RMSE = 3.8 and CV =4.1), days to maturity (RMSE = 11.9 and CV= 8.1), node number on main stem (RMSE = 1.7 and CV = 10.0), leaf area index (RMSE =0.8 CV =28.8), biological yield (RMSE = 158.5 and CV =21.6) and seed yield (RMSE = 118.6 and CV = 24.7). Therefore, the SSM_iCrop model can be used to evaluate the agronomic management and analyze the growth and yield of faba bean in Gorgan conditions.
Nasibeh Pourghasemian; Rohollah Moradi; Mehdi Naghizadeh
Abstract
In order to study the most suitable planting date, planting site and variety of hoary stock for the supplying at spring season, an experiment was conducted as split-split-plot arranged based on randomized complete block design with three replications at experiment station of Shahid Bahonar University ...
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In order to study the most suitable planting date, planting site and variety of hoary stock for the supplying at spring season, an experiment was conducted as split-split-plot arranged based on randomized complete block design with three replications at experiment station of Shahid Bahonar University of Kerman in 2016-2017. Treatments were planting dates (5 September, 5 October, 5 November, 5 December, 5 January) assigned to main plot, planting sites (inside and outside of greenhouse) as subplot and variety (two red and white ecotypes and two violet and pink breeding varieties) as sub-subplot. The significant difference of planting date was detected in plant height, number of days to budding and flowering, floret and inflorescence diameter, number of florets per plant, fresh weight of floret and plant, and vase life of flowers but did not detect in inflorescence height. The planting site had significant effect on all the traits except plant height, inflorescence height, and leaf number per plant. The results showed that the delay in planting decreased number of days to budding and flowering in all the varieties and both planting sites. The growth period of local varieties was longer than the breeding varieties, significantly. Planting outside the greenhouse had more appropriate conditions than inside. In general, planting the local red variety at 5 October and out of greenhouse conditions was the most suitable treatment for supplying the hoary stock to the market on the first of spring.
Javad Taie; Ebrahim Amiri; Ahmad Aien; Naser Boroumand; Mehrangiz Jokar
Abstract
Crop Simulation Models are advanced tools to estimate crop yield and optimizing of crop management practices. This study was conducted in order to evaluate DSSAT model under autumn cropping system condition in Jiroft, Iran, 2012-2014. The field experiment which repeated in two sequential years and three ...
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Crop Simulation Models are advanced tools to estimate crop yield and optimizing of crop management practices. This study was conducted in order to evaluate DSSAT model under autumn cropping system condition in Jiroft, Iran, 2012-2014. The field experiment which repeated in two sequential years and three replications were performed as randomized complete block design in split plots. The main factor was planting date (17th, 23th, 29th September and 5th October) and its subfactor was potato cultivars (Sante, Satina and Boren). Data of first and second years of field experiment was applied respectively for calibration and evaluation of model. Data-base requirement for model was created from 1. climatic data includes: temperature, radiation, relative humidity, wind and precipitation; 2. crop data attained from field experiment, 3. soil data. Results of statistical evaluation of model showed the good fitness of simulated and actual yield performance. Simulated tuber yields were similar to their observed value with RMSE of 19% (1210 kg/ha) and high correlation between observed and simulated tuber yield (R2>0.9). Simulated biomass had 2673.5 kg/ha difference to its observed value that showed low estimation precision (RMSE>30%). This model couldn’t predict tuber initiation stage correctly (RMSE>30%). Therefore, it was concluded that DSSAT model predicted potato yield correctly but due to weak precision in estimation of phenological stage, had low assurance for use in autumn cropping system of potato under autumn cropping system in Jiroft region.
Shiva Akbari
Abstract
The goal of this study was to investigate climatic factors, crop management and plant growth traits, using a simple model to simulate growth and yield of soybean in Tehran climatic condition in order to be use as an efficient tool to study effective factors on yield. The model was evaluated under Tehran ...
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The goal of this study was to investigate climatic factors, crop management and plant growth traits, using a simple model to simulate growth and yield of soybean in Tehran climatic condition in order to be use as an efficient tool to study effective factors on yield. The model was evaluated under Tehran condition. Soybean is one of the important resources of herbal oil and protein. At the current study, production and partitioning of dry matter in vegetative parts and grains of soybean were investigated by changing the parameters of base temperature, the maximum leaf area index and the fraction of crop total dry matter at the beginning of grain growth. Decreasing and increasing of base temperature caused to decrease and increase the phenological stages, changing the production of dry matter and the allocation of dry matter to vegetative organs and grains. Decreasing and increasing of the fraction of remobilized dry matter to grains lead to enhance and reduce harvest index, respectively. To model evaluation, some statistics on differences between observed and simulated values were used. The simulated yield ranges were within 1890-2220 kg.ha-1 with mean values of 1982.5 kg.ha-1 and the observed yield ranges were 1632-2254 kg.ha-1 with mean values of 2014.5 kg.ha-1. The RMSE was 178.48 kg.ha-1 that was equal to 9% of average of observed and predicted values. All data points were included at the 80% of 1:1 line and it indicated that the model had suitable accuracy to predict soybean yield in Tehran climatic condition.