masoud Naderi; M. Shayannejad; S. Heydari; B. Haghighati
Abstract
Introduction: Owing to drought, increasing demand for fresh water resources and low water use efficiency, the optimum use of water is essential in the agricultural sector. Therefore, this study was conducted to investigate the effect of different levels of irrigation water on quantitative and qualitative ...
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Introduction: Owing to drought, increasing demand for fresh water resources and low water use efficiency, the optimum use of water is essential in the agricultural sector. Therefore, this study was conducted to investigate the effect of different levels of irrigation water on quantitative and qualitative Characteristics of potato (Burren cultivar) and determination of its optimum consumptive use of water under Shahr-e kord environment.
Materials and Methods: This study was conducted at the Agricultural Research Center and Natural Resources in Shahr-e kord with longitude and latitude of 32˚18΄ and 50˚51΄ , respectively, in 2013. This experiment was performed in randomized complete block design with 7 treatments consisted of different levels of irrigation water and 3 replications. Different levels of irrigation water were: 40, 55, 70, 85, 100, 115 and 130 % of the soil moisture deficit. Potato seeds (burren cultivar) were planted with distance of 20 cm from each other and furrow width of 75 cm. Irrigation program were performed based on the measurement of soil moisture deficit. The irrigation intervals were considered as a fixed 7 day. Irrigation levels were applied to 105 days after planting and the total growth period was 130 days from planting to harvesting. The samples were taken from the two middle furrows. The evaluated parameters were included weight of tubers per plant, tuber diameter, weight of tuber in seed size, weight of tuber production in a plant in marketable size, tuber dry weight, the starch percent, percent of soluble sugars, nitrogen percent. The starch content was determined by Polarimetry method. The soluble sugars content was measured by Colorimetric method, the nitrogen content was measured by wet digestion method and using the Kjeldahl set. Then, the optimal depth of water consumption in conditions of limited water resources were determined by English method Statistical analysis of data and drawing graphs were done with SAS and EXCEL software, respectively.
Results Discussion: The effect of different levels of irrigation water on yield was significant at 1%. The yield increased with increase of irrigation water. The minimum and maximum yields were belonged to 40 and 130 % treatments with 13.2 and 45.2 tons per hectare, respectively. Whereas, the results revealed that treatments which recieved100, 115 and 130% of the soil moisture deficit had no significant effect on potato yield at 5% level. Thus, potato yield in 115 and 130% treatments were only 2.3 and 3.9% more than treatment receiving full irrigation, respectively. The potato production function was obtained using the depth of water which consumed during the growing season and yield in each treatment. The results showed that the effect of different levels of irrigation water was significant on yield, starch, soluble sugars, dry matter, irrigation water use efficiency and the weight of tuber production per plant in marketable size As the level of irrigation water increased, the yield, soluble sugars content and weight of tuber per plant in marketable size increased and the starch and dry matter content decreased. Moreover, effect of different levels of irrigation water on nitrogen percent and the weight of tuber in seed size were not significant. Maximum and minimum of irrigation water use efficiency were belonged to 85 and 40% with values of 6.96 and 4.84 Kg m-3, respectively. Maximum and minimum percentages of starch were belonged to 40 and 130% treatments with values of 76.6 and 61%, respectively. The soluble sugar content in potato can causes discoloration and darkness of the product, and accordingly it makes the non-marketability of the product. Maximum and minimum soluble sugar contents were belonged to 130 and 40% treatments with values of 2.12 and 3.07%, respectively. In addition, the increase of irrigation water caused to the increase of weight of tuber per plant in marketable size. Therefore, the highest marketable tuber yield was belonged to 130% treatment and it was 1.5 kg per plant and the lowest one was belonged to 40% treatment and it was 0.61 kg per plant. The applied water which maximized the income was 821 mm during the growth period.
Conclusion: The use of 82% full irrigation (533mm) can result in maximum net income and irrigated area can increase by 22% compare to full irrigation. If the purpose of planting is get to the maximum yield, the use of 130% irrigation treatment is recommended and if the purpose is the production of seed potatoes, the use of 85% irrigation, treatment is recommended.
N. Najafpour; M. Shayannejad; hossein samadi
Abstract
Pore pressure, seepage and drainage discharge through in earthen dams are the most important characteristics that have to be defined in order to analysis an earth dam. These parameters have been measured since beginning of building dam. In this investigation, a physical model of homogenous earth dam ...
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Pore pressure, seepage and drainage discharge through in earthen dams are the most important characteristics that have to be defined in order to analysis an earth dam. These parameters have been measured since beginning of building dam. In this investigation, a physical model of homogenous earth dam created in the flume with three different angles of toe drain, then pore pressure of earth dam was measured by piezometers that put on the wall of the flume. Discharge of drainage was measured too. The seepage analysis was conducted by PLAXIS software then Result of the PLAXIS compare with physical model by SAS (Statistic software) and finally the best angle and without dimension index ,p/h, propose for toe drain according to results & observations.
F. Mostashfi HabibAbadi; M. Shayannejad; M. Dehghani; S.H. Tabatabaei
Abstract
Abstract
The irrigation water quality is not suitable for crop production in most regions of Iran. It is estimated that almost six BCM/year of saline water enter to the rivers, in Iran. The saline water can potentially use for growing of tolerant crops with a specific management on the agriculture practice. ...
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Abstract
The irrigation water quality is not suitable for crop production in most regions of Iran. It is estimated that almost six BCM/year of saline water enter to the rivers, in Iran. The saline water can potentially use for growing of tolerant crops with a specific management on the agriculture practice. One of the management methods is the conjunction use of fresh and saline water. In this study, four conjunctive use of saline and fresh water is evaluated on yield and yield components of two sunflower cultivars. A split plot design was employed in completely randomize block form with eight treatments and four replication. The main level has two sunflower cultivars (Alestar and Haisan33) and in the sub main level, four irrigation regimes was exist (1- Irrigation with half saline water and then one half with fresh water, 2-Irrigation with half fresh water and then one more half with saline water, 3- Alternate irrigation with fresh and saline water 4-Conjunction irrigation). To prevent salt, the plots were irrigated with fresh water for the first three irrigation events. The treatments were applied up to the harvesting. The result shows that the saline- fresh irrigation regime had the highest yield index concerning oil, 100 seed's weight, seed yield, seed yield per capital, stem diameter, flower height, capital diameter, leaf area and leaf minerals. For Haisan33 cultivar the alternate regime and for the Alestar cultivar the conjunction regime was in the second grade.
Keywords: Saline water, Irrigation Management, Sunflower, Yield index
