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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.
Fakhroddin ghassemi sahebi; Omolbani Mohammadrezapour; Masoomeh Delbari; Abbas KhasheiSiuki; Ali Cherati
Abstract
To investigate the effect of unconventional water and zeolite on yield and water use efficiency of sorghum, a split plot experiment was conducted based on randomized complete block design with 3 replications, at Gharakhil Agricultural Research Station in Ghaemshahr, Mazandaran Province. In this experiment, ...
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To investigate the effect of unconventional water and zeolite on yield and water use efficiency of sorghum, a split plot experiment was conducted based on randomized complete block design with 3 replications, at Gharakhil Agricultural Research Station in Ghaemshahr, Mazandaran Province. In this experiment, the main treatment was irrigation water quality (well water as control (W1); 75% well water and 25% seawater (W2); 25% well water and 75% seawater (W3); 100% treated urban wastewater alternated with 100% seawater (W4); 50% seawater and 50% urban treated wastewater (W5); irrigation with urban treated wastewater (W6)), and sub-treatment included three levels of zeolite as soil amendment (without zeolite Z1, calcic zeolite Z2, and potasic zeolite Z3). The results of data analysis showed that irrigation water quality treatments and zeolite levels had a significant (P<0.05) effect on plant yield. With increasing salinity, the yield of fresh and dry fodder sorghum decreased, but no significant difference was observed between treatments W5 and W4. The fresh and dry fodder yield in treated wastewater with calcic zeolite was higher than other treatments. The highest leaf area index was recorded in W6Z2 treatment (7.62) and the lowest was in W3Z1 treatment (3.80). The highest water use efficiency of fresh forage was observed in W6Z2 treatment (12.7 kg/m3) and the lowest in W3Z1 treatment (4.62 kg/m3).
Habibeh Jahanbakhsh; ali modares; Hamed Keshavarz; mehdi panahi
Abstract
Physiological study of crops under microclimatic changes is very important to improve their production in the future. This research was done in Tarbiat Modaress University Research Greenhouse as factorial arrangement in randomized complete block design with three replications in one year (2015). The ...
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Physiological study of crops under microclimatic changes is very important to improve their production in the future. This research was done in Tarbiat Modaress University Research Greenhouse as factorial arrangement in randomized complete block design with three replications in one year (2015). The objective was to study the effects of carbon dioxide (500, 900, and 1300 ppm), UV-radiation (UV-A, B, and C with intensity of 18, 25 and 40 µW.cm2, respectively) and two irrigation water treatments (full irrigation and deficit irrigation i.e. 60 percent of field capacity) on yield and yield components of sweet corn. Plant height showed a direct relation with the amount of irrigation water and decreased about 10 percent under water deficit stress. The interaction of carbon dioxide and water deficit as well as the interaction of UV-radiation and carbon dioxide reduced the number of leaves below the corns, although this decrease was not significant. Water deficit reduced Specific Leaf Area and Leaf Area Index by, respectively, 11% and 19% relative to the control. In full irrigation, carbon dioxide concentration and number of seeds in each row had direct relation, but under water deficit condition, they had indirect relation. Ultraviolet radiations wave length reduction reduced yield. Water deficit reduced Specific Leaf Area and number of seed in corn row. UV-A and B wave length did not significantly affect yield, but UV-C radiation decreased it. In brief, increase in UV wave length under drought conditions led to decrease in leaf number, leaf area, and yield.
Mohammad Zounemat Kermani; rasool asadi
Abstract
Considering the limited water resources in arid and semi-arid climate of Iran, deficit irrigation is one of the strategies for efficient use of water and increasing water use efficiency in agricultural districts. In order to study the effects of deficit irrigation on the quantitative traits of ...
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Considering the limited water resources in arid and semi-arid climate of Iran, deficit irrigation is one of the strategies for efficient use of water and increasing water use efficiency in agricultural districts. In order to study the effects of deficit irrigation on the quantitative traits of Thymus vulgaris L., an experiment was conducted in Kerman Municipality seedling production station in 2016. The experimental treatments were arranged as randomized complete block design with three replications. The irrigation regimes consisted of full irrigation (FI-100), regulated deficit (RDI75% and RDI55%) and partial root zone drying irrigation (PRD75% and PRD55%). The results showed that the highest herbage dry weight (1670.6 kg/ha) and leaf area index in different stages of growth were produced by full irrigation treatment, while no significant difference between this treatment and PRD75 was observed. Also, the highest number of shoots (64.4) and plant height (39.4 cm) were produced by full irrigation treatment and there was significant difference between this treatment and other treatments. However, the highest water use efficiency (0.66 kg/m3), root fresh weight (4.5 g), root depth (15.8 cm) and root volume (2.8 cm3 per plant) appeared in PRD75. Therefore, 75 percent water replacement in partial root zone drying irrigation treatments, in addition to saving water consumption, provides better use of soil moisture and sunlight. Thus, this treatment can be considered as suitable approach to cope with the water crisis and achieve a sustainable agriculture.
A GH; A SH; M R; H Z
Abstract
Deficit irrigation, as a limiting factor for growth, will affect physiological characteristics of plants. In order to investigate the effects of deficit irrigation on yield, chlorophyll fluorescence, dry weight of stems and leaves, and leaf area index of sunflower, this study was performed at the research ...
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Deficit irrigation, as a limiting factor for growth, will affect physiological characteristics of plants. In order to investigate the effects of deficit irrigation on yield, chlorophyll fluorescence, dry weight of stems and leaves, and leaf area index of sunflower, this study was performed at the research farm of Agriculture and Natural Resources University of, Sari, Iran, in 2013. The experimental treatments were arranged as randomized complete block design with three replications. The irrigation regimes consisted of full irrigation (FI), regulated deficit (DI75, DI55), and partial root-zone drying irrigation (PRD75, PRD55). The results indicated that the effect of irrigation treatments on yield, photosynthetic efficiency, maximum fluorescence (Fm), minimum fluorescence (Fo), leaf area index, shoot dry weight, leaf dry weight, and head dry weight was significant. Comparison showed that water stress significantly decreased grain yield, photosynthetic efficiency index and maximum fluorescence (Fm), whereas the minimum fluorescence (Fo) was increased. The maximum seed yield (5148 kg ha-1) was attained in full irrigation treatment and had no difference with PRD75 treatment. The maximum leaf area index at the end of the growing season was 4.3 and recorded in FI and had no difference with PRD75, DI75 and PRD55. Overall, treatment PRD75 is recommended since it reduced water consumption by 16.8 percent relative to FI treatment and had no significant difference with full irrigation treatments (FI) in terms of seed yield, quantum yield, and other growth parameters.