ahmad zare; aydin khodaeaei; zienab khezrepoor
Abstract
In order to evaluate the response from chia (Salvia hispanica L.) to temperature, under abiotic stresses (salinity and drought) three separate experiments was carried out in the laboratory of Agricultural Sciences and Natural Resources at University of Khuzestan in four replications in 2018. Treatments ...
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In order to evaluate the response from chia (Salvia hispanica L.) to temperature, under abiotic stresses (salinity and drought) three separate experiments was carried out in the laboratory of Agricultural Sciences and Natural Resources at University of Khuzestan in four replications in 2018. Treatments included temperature (5, 10, 15, 20, 25, 30, 35, 40 and 45 °C), salinity (0, 50, 100, 150, 200, 250, 300, 350, and 400 mM), and drought stress (-0.2, -0.4, -0.6, -0.8, -1, 1.2, and 1.4 MPa). In response to temperature, chia proved to be capable of germinating in the range of 10 to 40 °C. The base temperature, optimum temperature, and ceiling temperature were predicted to be 6, 28, and 44°C respectively. Germination percentage and germination rate decreased in response to salinity and at salinity of 400 mM, germination was completely inhibited. Salinity reduction of 50% in germination percentage and germination rate obtained at salinity 349 and 236 mM. 50% reduction in germination percentage and germination rate was observed at -0.92 and -0.79 MPa of drought stress. According to x50 parameter, chia is resistant to salinity and drought stresses. In conditions of saline soils and drought stress, it can be recommended for cultivation to farmers.
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.