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esmaeel mir; halimeh piri; Amir Naserin
Abstract
Carla is a medicinal plant whose fruit is used to treat diabetes. In this study, the effect of water stress and biochar on the qualitative and quantitative parameters of Carla plant was investigated. The experiment was performed in greenhouse conditions in a factorial manner and in a completely randomized ...
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Carla is a medicinal plant whose fruit is used to treat diabetes. In this study, the effect of water stress and biochar on the qualitative and quantitative parameters of Carla plant was investigated. The experiment was performed in greenhouse conditions in a factorial manner and in a completely randomized design with three replications. Treatments included three irrigation water treatments (50%, 75%, and 100% of the water requirement) and four biochar treatments (zero, 1.25%, 2.5%, and 5% by weight of potting soil). During the growing season, water treatments were applied by weekly weighing of the pots and replenishing the water loss up to Field Capacity. The amount of water added to each pot was measured. Harvest at 50 days after planting was done once a week. A total of five harvests were performed. In each harvest, quantitative parameters including plants height, number, weight, diameter and length of fruit, and qualitative parameters of fruit sugar content, greenness index, and leaf area index in each pot were carefully measured. Also, the yield and efficiency of irrigation water consumption at the end of the planting season was determined in each treatment. The results showed that the effects of irrigation water and biochar levels were significant (at 1% and 5% probability) on the measured parameters. With decrease in irrigation water, the amount of quantitative parameters and plant yield decreased. The highest value of the measured parameters was obtained from 100% irrigation water treatment, which was not significantly different from the 75% irrigation water treatment. The use of biochar up to 2.5% by weight of soil increased the parameters. Use of the right amount of biochar reduces the negative effects of stress and improves plant growth compared with the control treatment. Therefore, use of biochar for plants, especially when the plant is under water stress, can be recommendable. In order to reduce the amount of water used in greenhouses and improve plant growth and yield, biochar use is advisable, however, its use under field conditions should be tested.
halimeh piri; Hossein Ansari; m p
Abstract
The main factor for managing and scheduling irrigation in dry area, is the plant response to drought stress. The majority of irrigation water in these areas contains soluble salts, therefore, salinity stress should be considered at the same time. Hence, this study was conducted in order to obtain ...
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The main factor for managing and scheduling irrigation in dry area, is the plant response to drought stress. The majority of irrigation water in these areas contains soluble salts, therefore, salinity stress should be considered at the same time. Hence, this study was conducted in order to obtain the optimum depth of irrigation, considering drought and salinity stress individually and simultaneously, at three cutting times of forage sorghum in Sistan plain.This experiment used split plot in time in a factorial design with three levels of salinity (2, 5, and 8 dS.m-1) and four irrigation levels (50%, 75%, 100%, and 120% water requirement) at three cutting stages, with three replications. The depth of the water was determined for salinity levels and at various cuttings. In order to determine the separate and combined effects of salinity and irrigation water, the following criteria were used were used in each cutting: the index of final production compared to irrigation water depth (MPI), the final production compared to the salinity (MPECw), marginal rate of technical replacement for salinity and water (MRTSI, ECw ), the final output value of the irrigation water depth (VMPI), and the final output value of the salinity (VMPECw). MPI index showed that for each one centimeter increase in irrigation water depth, the first cutting had the least change in production(1.22 ton.ha-1) and the third cutting had the maximum amount (9.2 ton.ha-1). MPECw index showed that in the low salinity treatments, the second and third cuttings had, respectively, the lowest and the highest yield loss. MRTS index showed that in order for production to stay the same with one unit increase in salinity, the irrigation water depth must increase in the first, second, and third cuttings by, respectively, 5.86, 1.97 and 1.72 centimeter. Also, with increasing salinity levels in the all three cutting, optimum irrigation depth increased and in the all salinity levels, optimum irrigation depth in the first cutting was more than the second cutting, and in the second cutting it was more than the third cutting.
halimeh piri; Hossein Ansari; m p
Abstract
Water stress and salinity are among the problems of agricultural production in many parts of the world. In this study, the effect of salinity (2, 5 and 8 dS/m), different irrigation levels (120%, 100%, 75%, and 50% of water requirement) and three harvesting times (cuttings) were investigated on some ...
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Water stress and salinity are among the problems of agricultural production in many parts of the world. In this study, the effect of salinity (2, 5 and 8 dS/m), different irrigation levels (120%, 100%, 75%, and 50% of water requirement) and three harvesting times (cuttings) were investigated on some qualitative and quantitative parameters of sorghum silage in the Sistan region. The study was carried out using a factorial split plot design with 12 treatments and 3 replications. The results showed that increasing salinity and irrigation water depth decreased fresh and dry matter yield. However, no significant difference was observed between 100% and 75% crop water requirement treatments. Also, treatments with 2 and 5 dS/m salinity were not significantly different in feed production. Furthermore, the fresh and dry forage yields were higher in the second cutting than in the first and third harvesting. Decrease in irrigation water and increase in salinity decreased protein but increased carbohydrate and proline. The highest amount of protein (16.79 percent) was obtained in the second harvesting and at the salinity of 2 dS/m, while the highest amount of carbohydrates (10.79 mg/gFW) and proline (0.42 mg/gFW) belonged to the third harvesting with salinity of 8 dS/m. By increasing salinity in irrigation water and with the passage of time during the growing season, soil salinity increased and distribution of salinity in the soil profile was more uniform in the treatments that had no water stress. Thus, according to the results, 25% of the plant water consumption can be saved and irrigation with 75% of water requirement and salinity of 5 dS/m would have no significant effect on the amount of forage produced. The best forage quality for livestock consumption was obtained in the second harvesting. However, this experiment was done in one growing season and in the long time reduction in the amount of water and the use of salt water can cause soil salinization and accumulation of salts in the soil. Therefore, it is recommended that the experiment be repeated in the future, before making a final decision about reducing irrigation water.