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Investigation of the Effect of Seed Burial Depth, Duration, and Seed Shape on the Germination of Seed of Common Hedge Parsley (Torilis arvensis Huds.) Полный текст
2024
Bahrami Shad, Maryam | Boromandan, Pardis | Nosratti, Iraj
Spreading hedgeparsley is a weed of wheat fields which thier seed bank is increasing in Kermanshah province. The aim of this study was to investigate the effect of time, burial depth, and seed shape in the field. This study was conducted as a factorial experiment in a completely randomized design with 3 replications. Both hairy and non-hairy forms of spreading hedgeparsley seeds were placed in different depths of storage (control), zero (soil surface), 5, 10, 20, and 40 cm of soil, and then seeds digged out from soil at 3, 6, 9, and 12 months burial time. The results showed that the effect of time, burial depth, and seed shape treatments on germination was significant in the field. The highest percentage of spreading hedgeparsley seed germination was observed in the first 3 months after burial. In general, the percentage of seed germination decreased by time. At a depth of 5 cm in the soil due to the favorable environmental conditions such as temperature, light and oxygen, the highest germination percentage was observed. Seed germination percentage decreased with increasing depth. The percentage of germination of spreading hedgeparsley seeds was higher than that of spinyseeds due to the level of contact of seeds with light, temperature and humidity.
Показать больше [+] Меньше [-]Simulation of Replacing Wheat with Rapeseed in Terms of Water and Economic Productivity in Lorestan Province Полный текст
2024
Soltani, Fatemeh | Rahimi-Moghaddam, Sajjad | Akbari, Naser | Azizi, Khosro | Eyni-Nargeseh, Hamed
After soybean and oil palm, rapeseed has the third place in supplying vegetable oil in the world, so that it accounts for 14.7% of the total production of vegetable oil. The current research was carried out using modeling approach in order to simulate the replacement of wheat cultivation with rapeseed cultivation in terms of water and economic productivity in four locations (Aleshtar, Khorramabad, Pol-e Dokhtar, and Kuhdasht) in Lorestan province. APSIM model was used to simulate the growth and yield of wheat and rapeseed crops. The model validation results showed that it accurately simulates wheat and rapeseed grain yield with nRMSE of 8.6%. The results showed that wheat cultivation (3524.4 kg) had a higher grain yield than rapeseed cultivation (2750.2 kg). In addition, wheat cultivation system (1.45 kg m-3) compared with rapeseed cultivation (1.15 kg m-3) had higher water productivity. However, the difference between these two cultivation systems in terms of irrigation productivity was not considerable (0.11 kg m3). Also, economic productivity and net income of rapeseed cultivation system were 0.220 million tomans per cubic meter and 59.9 million tomans per hectare, respectively, while they were 0.014 million tomans per cubic meter and 41.1 million tomans per hectare, respectively, for wheat cultivation system. In general, the results approved that moving from wheat cultivation to rapeseed cultivation can be environmentally and economically sustainable in the agro-ecosystems of Lorestan province, especially in Khorramabad county.
Показать больше [+] Меньше [-]Investigating Genetic Diversity of Imported Quinoa (Chenopodium quinoa Willd) Genotypes Using Morphological-Phenological Traits Полный текст
2024
Sourilaki, Ebrahim | Rabiei, Babak | Hosseini Chaleshtori, Maryam | Jokarfard, Vahid
Considering the high production potential of quinoa plant, especially under stressful conditions such as drought and salinity, it is necessary to introduce new and high-yielding genotypes for cultivation in different regions of Iran. The objective of this research was to evaluate the diversity of 26 new and foreign quinoa genotypes in terms of morphophenological characteristics. The experiment was carried out in a completely randomized design with three replications in greenhouse of Rice Research Institute of Iran (RRII), Rasht, in 2021. The results of analysis of variance showed that there was a very significant statistical difference among the studied genotypes for all measured traits. Factor analysis using the principal components method identified three main and independent factors that explained 39.19, 24.63, and 15.94%, respectively, and in total about 80% of the total variance. In addition, cluster analysis based on Ward's minimum variance grouped the studied 26 quinoa genotypes into three separate clusters; including 14, 7, and 5 genotypes, which very largely corresponded to grouping of the principal components. In total, the results of the current study showed that among the studied 26 quinoa genotypes, genotype No. 12 with 1000-grain weight, panicle length, and grain yield higher than the other genotypes as well as dwarfism and earliness characteristics was the most valuable genotype of this experiment. Furthermore, genotypes No. 4, 8, 17, and 18 for grain yield, genotypes No. 7, 13, and 15 for earliness, and genotype No. 14 for dwarfism, were the promising genotypes of this research, which can be used to transfer earliness and dwarfism to high-yielding genotypes in future breeding programs.
Показать больше [+] Меньше [-]The Interaction of Planting Date and Irrigation Regime Effects on the Yield and Water Use Efficiency of Milk Thistle (Silybum marianum) Ecotypes Полный текст
2024
Samieadel, Shiba | Eshghizadeh, Hamid Reza | Zahedi, Mortaza | Majidi, Mohammad Mahdi
This study aimed to investigate the response of four ecotypes of milk thistle from Isfahan, Kohgiluyeh va Boyer Ahmad, Khuzestan-Omidiyeh, and Hungary to three irrigation regimes (irrigation after 40%, 60%, and 80% maximum allowable depletion of available soil water (evaluated in 2020-2021 under five different planting dates (September 27th, October 17th, November 6th, November 26th, and March 10th) at the research farm of Isfahan University of Technology in Iran. The experiment was conducted as a combined analysis of a split-plot based on randomized complete block design with three replications. The results showed that the highest and the lowest grain yield and shoot dry weight of milk thistle plants were obtained under the October 17th and March 10th planting dates, respectively. Water deficit at both levels decreased grain yield, shoot dry weight, number of flowers per plant, plant height, flowering degree-days, and physiological maturity degree-days, but increased grain and shoot water use efficiencies. The "Kohgiluyeh and Boyer Ahmad" ecotype exhibited the highest seed yield, shoot dry weight, seed/shoot water use efficiency, and harvest index, making it a promising candidate for breeding programs aimed at creating adaptive cultivars of the milk thistle plant. Based on the study's findings, it can be concluded that milk thistle should be planted in the fall season from late September to mid-November under similar climate conditions.
Показать больше [+] Меньше [-]Effects of Drought Stress and Re-Irrigation at the Flowering Stage on the Physiological and Biochemical Responses and Yield in Promising Lentil Lines Полный текст
2024
Azizi, Solmaz | Zare, Nasser | Sheikhzadeh, Parisa | Azizi Mobser, Javanshir | Karimizadeh, Rahmatollah
Rapid and efficient recovery from water deficit stress may be one of the key determinants of drought adaptation in plants. The present study was designed to investigate drought stress tolerance and recovery in promising lentil lines at the flowering stage. For this, a factorial experiment based on the completely randomized design was conducted with three replications. The factors included 6 lentil lines, drought stress (control (irrigation at 80% FC or 20% moisture depletion), medium stress (irrigation at 55% FC or 45% moisture depletion), and severe stress (irrigation at 30% FC or 70% moisture depletion)), and three sampling times (three and six days after drought, and recovery (two days after re-irrigation)). Drought stress caused a decrease in chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, protein, yield, and yield components. The reduction of these traits was more remarkable at six days after stress. However, during the recovery time remarkable increase was observed in these traits. The results showed that the correlation between H2O2 and MDA was significant and positive. Furthermore, drought stress increased the amount of proline, H2O2, and MDA, which resulted in an increase in the activity of antioxidant enzymes (catalase, polyphenol oxidase, and peroxidase). An increase in the intensity and duration of the drought stress also caused an increase in H2O2 and MDA content and the activity of antioxidant enzymes. In addition, in the recovery conditions, a significant reduction in the destructive effects of stress (H2O2, MDA content) and the activity of antioxidant enzymes was visible. The results of the present study indicated that the effects of drought stress on lentil lines yield and yield components (seed number, number of pods, 100-seed weight, and seed yield) were varied. Drought stress at the flowering stage decreased the number of seeds and pods per plant, and 100-seed weight, which led to yield losses. Although line 2 had the highest yield under normal and drought stress conditions, line 1 exhibited the lowest yield under stress conditions. Based on the results of this experiment, line 2 seems to be a suitable line for culture in the regions challenged with water deficit stress.
Показать больше [+] Меньше [-]Effect of Foliar Application of Amino Acids under Water Deficit Conditions during Late-Season on Yield and Yield Components of Oil Rapeseed (Brassica napus L.) Полный текст
2024
Fayaz, Esmaeil | Sorooshzadeh, Ali | Heidarzadeh, Ali
This study was conducted to investigate the effect of foliar application of amino acids on yield and yield components of oil rapeseed under late-season drought stress conditions. The experiment was conducted as factorial based on a randomized complete blocks design in the research farm of the Faculty of Agriculture at Tarbiat Modares University during the 2021-22 growing season. The experimental treatments were irrigation regimes at three levels (normal irrigation, withholding irrigation from 50% flowering stage, and withholding irrigation from pod forming) and foliar spraying at five levels (no foliar, foliar spraying 0, 1, 2, and 3 g amino acids per liter of distilled water). The results showed that plant height, shoot dry weight, 1000-seed weight, harvest index, and biological and grain yield, number of seeds per pod, and the number of pods per plant were significantly affected by the interaction of irrigation regimes and foliar spraying. The highest plant height (166.5 cm), 1000-seed weight (3.58 g), number of pods per plant (131.4) and grain yield (4514 kg ha-1) were obtained by foliar spraying of two g amino acids per litre under normal irrigation conditions. According to the results, foliar spraying 2 g amino acids per liter had the most positive effect on the yield and yield components of oil rapeseed in all irrigation regimes (normal irrigation, withholding irrigation from 50% flowering stage, and withholding irrigation from pod forming). Therefore, upon approving in future research it could be recommended to use foliar spraying with 2 g amino acids per liter in oil rapeseed cultivation.
Показать больше [+] Меньше [-]Comparison of Bread Wheat Genotypes and Correlation Analysis of Traits in Different Moisture Conditions based on GT-Biplot Method Полный текст
2023
Bavandpouri, Fatemeh | Farshadfar, Ezatollah | Farshadfar, Mohsen
In order to compare 25 genotypes of bread wheat in terms of morpho-physiological and biochemical traits, an experiment was conducted in a randomized complete blocks design with three replications in the rainfed and irrigated conditions at Razi University, Iran, in 2016-2017. GT-biplot was used to evaluate genetic diversity and to identify stable genotypes with high yield and drought tolerance. Combined variance analysis showed that there was high variability among genotypes for the most of traits. Examining the correlation of traits in two environmental conditions showed that morpho-physiological traits; especially yield components, were the most related to yield. The results of the GT-biplot method showed that the first and second principal components explain 41.7% and 40.1% of the total changes in rainfed and irrigated conditions, respectively. Based on the GT-biplot analysis diagrams of genotypes 10, 15, 6, 13, 2, 14, and the Pishtaz cultivar in terms of physiological traits, yield and its components and the traits related to stem and spike in irrigated conditions, and genotypes 10, 15, 6, 18, and 17 in terms of biochemical traits, yield and its components, and traits related to stem and spike in rainfed conditions were recognized as superior genotypes. The genotypes 2 and 6 in irrigated conditions and the genotype 6 in rainfed conditions had the lowest genotype×trait interaction. Finally, the genotypes 10, 15, and 6 were superior in two environmental conditions and the genotype 6 had the least interaction effect in both conditions. Therefore, these genotypes can be used in breeding programs.
Показать больше [+] Меньше [-]Recovery potential of sensitive and tolerant genotypes of sunflower post drought stress conditions Полный текст
2023
Akbari, Nasrin | Darvishzaeh, Reza
Sunflower is one of the most important oilseed crops with more than 50% of nutritional (table) consumption. Considering the climate changes, the development of genotypes tolerant to abiotic stresses is more important than before. In the present research, the recovery capacity of two oilseed sunflower genotypes (DM-2 and H158A/H543R) was evaluated 24 hours after irrigation following sever drought stress (30% of field capacity) by evaluating the changes in enzymes activity at 8-leaf stage and quality and quantity of end product at adult plant stage. The experiments were conducted in frame of completely randomized design with 3 replications under controlled conditions. A significant difference was observed between genotypes in the terms of guaiacol, ascorbate, lipoxygenase and proline contents, as well as leaf area, leaf length, root weight, plant height and root sodium-potassium ratio in recovery conditions. Based on the results of the evaluations and changes in the mean of traits in the comparison of two normal and recovery conditions, as well as the pattern of fatty acids, genotype DM-2 has a high recovery ability.
Показать больше [+] Меньше [-]Simulating the Effects of Climate Change on Irrigated Barley (Hordeum vulgare) in Lorestan and Hamedan Provinces Полный текст
2023
Valipoor, Ali | Azizi, Khosro | Rahimi Moghadam, Sajad
The present research was conducted to simulate the impact of climate change on irrigated barley in Lorestan and Hamadan provinces. For this purpose, nine regions including Aligudarz, Borujerd, Khorramabad, Kuhdasht, Pol-e Dokhtar, Hamedan, Malayer, Nahavand, and Kabudarahang were selected in the two provinces. The APSIM-barley model was employed to simulate the growth and development of irrigated barley. Firstly, the APSIM-barley model was evaluated using two independent field experiments. The first experiment was conducted in Khorramabad to calibrate the crop model; while the second experiment was done in Hamedan to validate the crop model. The future climate was projected using the AgMIP methodology under two scenarios (RCP4.5 and RCP8.5) for the period 2040-2070. The results of the model validation showed that the crop model was able to simulate barley yield and biomass with nRMSE of 16.4% and 13.3%, respectively. Additionally, the results indicated that on average across the study locations, barley grain yield would decrease by 3.8% and 5.7% under RCP4.5 and RCP8.5, respectively. However, in Pol-e Dokhtar, barley grain yield is projected to increase by 1.3% and 4.8% under RCP4.5 and RCP8.5, respectively. Based on these findings, adaptation strategies should be considered in the future to prevent the reduction of irrigated barley yield in the studied provinces.
Показать больше [+] Меньше [-]Evaluating the Effect of Vrn-B1 and Vrn-D1 Genes on Drought Tolerance of Bread Wheat Using Isogenic Lines Полный текст
2023
Pourtabrizi, Soraya | Kazemipour, Ali | Mohamadinejad, Ghasem | Khajoei, Ghlamreza | Abdolshahi, Rohollah
Vernalization genes (Vrn), in addition to controlling the growth habit of wheat (spring and winter), play a key role in flowering time and early maturity of wheat. They are also of great interest in drought tolerance researches. To investigate the effect of Vrn genes on drought tolerance, four isogenic lines were developed. Isogenic lines were resulted from the crosses of the early heading Australian variety, Excalibur, with the late heading Iranian variety, Roshan, and followed by backcrossing with Roshan. Two experiments were conducted based on randomized complete block design with four replications under rainfed conditions of Sepidan during 2019-2020 and under well-watered conditions of Kerman during 2020-2021 cropping years. In the present research, seven important agronomic traits, including days to heading, days to ripening, grain filling period, spike number per meter square, grain number per spike, 1000-grain weight, and grain yield were assessed. Isogenic lines were assessed for drought tolerance using eight indices, including mean of productivity (MP), yield index (YI), stress tolerance index (STI ), geometric mean of productivity (GMP), stress susceptibility index (SSI ), yield stability index (YSI), and stress tolerance score (STS). The results of stress tolerance score (STS) showed that isogenic lines vrn-B1/Vrn-D1a and Vrn-B1a/vrn-D1 had the highest and the lowest stress tolerance score, respectively. In addition, the vrn-B1 and Vrn-D1a alleles, which cause early flowering, improve drought tolerance by utilizing an escape mechanism from dry conditions.
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