Nader Khadem Moghadam Igdelou; Ahmad Golchin; Khadije Farhadi
Abstract
In order to study the effect of Cobalt, Molybdenum, and Nitrogen on the growth of Phaseolus vulgaris in soilless culture, a pot experiment was conducted in 2015-16 and in July, at 25˚C and light intensity of 40,000 lux as a factorial based on a CRD with 36 treatments and three replications in the greenhouse ...
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In order to study the effect of Cobalt, Molybdenum, and Nitrogen on the growth of Phaseolus vulgaris in soilless culture, a pot experiment was conducted in 2015-16 and in July, at 25˚C and light intensity of 40,000 lux as a factorial based on a CRD with 36 treatments and three replications in the greenhouse of Zanjan University. The test factors consisted of four levels of Nitrogen (50, 100, 150, and 200 mg/l), three levels of Molybdenum (0.067, 0.2, and 0.6 mg/l) and, three levels of Cobalt (0.006, 0.06, and 0.3 mg/l). Factor levels were prepared by adding ammonium nitrate, ammonium molybdate, and cobalt chloride to a stock solution. Results of morphological traits showed that the highest pod dry weight was obtained in N100Mo0.6Co0.06 treatment which had a maximum difference of 47.9% with other treatments. The highest dry weight of shoots was obtained from N150Mo0.6Co0.006 treatment and the highest root dry weight was obtained from N150Mo0.6 and N150Co0.3 treatments. Also, the highest number of pods was obtained in N150Mo0.6, N100Co0.3 and Mo0.6Co0.3 treatments with values of 235.2, 266.4, and 220.8 g/pot, respectively. Investigation of physiological traits showed that the highest concentrations of Nitrogen, Molybdenum, and Cobalt were obtained from N200Mo0.6Co0.3, N150Mo0.6Co0.3, and N150Mo0.067Co0.006 treatments, respectively. Overall, it can be stated that the application of N100Mo0.6Co0.06 treatment can positively affect the dry weight of pods, which are economically productive and improve the performance of P. vulgaris (Talash cultivar).
Hajar Ashoordan; Massoud Dehdari; Asad Masoumiasl; Rahmatollah Karimizadeh
Abstract
Objective: Cold stress causes irreparable losses to plants including lentils (Lens culinaris Medic) as one of the important legumes. Limited information is available on the use of somaclonal variation for improving cold tolerance in lentils. This study aimed to investigate the cold tolerance in lentil ...
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Objective: Cold stress causes irreparable losses to plants including lentils (Lens culinaris Medic) as one of the important legumes. Limited information is available on the use of somaclonal variation for improving cold tolerance in lentils. This study aimed to investigate the cold tolerance in lentil seedlings regenerate from in vitro culture.
Methods: To investigate cold tolerance, regenerated seedlings of seven lentil genotypes were exposed to two temperature conditions of 5 and 25˚C. The experiment was conducted at each temperature level in a completely randomized design with three replications at the Yasouj Agricultural Faculty in 2021. Ten days after application temperature treatments, physiological and morphological traits including root length, root fresh and dry weight, shoot height, shoot fresh and dry weight, carotenoid and chlorophyll contents, electrolyte leakage and total soluble sugar content were measured.
Results: The results of the combined analysis of variance showed that the effect of temperature for all traits; the effect of genotype for all traits except root length, and the interaction of temperature and genotype for all traits except shoot height, carotenoid, and chlorophyll content were significant. At the temperature of 5˚C (cold stress), the genotype 09S 83259-14ILL6994/ILL5480 had more values than the other genotypes in terms of most traits. Classification of genotypes using the three-dimensional plot of the first three factor scores introduced the genotypes ILL 7979 and 09S 83259-14ILL6994/ILL5480 as the most tolerant genotypes under cold stress conditions. The genotypes Gachsaran, Kimia, ACC 5588 ILL116 Sel and ACC 4605 were identified as cold-sensetive. Among the traits measured at the vegetative stage, the electrolyte leakage trait had the highest stress intensity value (0.53), indicating that this trait was more affected by cold temperature than other traits. The genotypic and phenotypic variation coefficients showed that the genotypes had the most diversity for the measured traits related to the shoot. The highest broad-sense heritability was related to total soluble sugar (97.81%) and electrolyte leakage (97.70%), and the lowest was related to root length (88.02%).
Conclusion: In general, the results showed that there was sufficient genetic diversity of cold tolerance among the seedlings regenerated from the tissue culture of the genotypes. In this study, by measuring the components of genetic variance, it was determined to some extent that the contribution of genetic variance is greater than epigenetic factors for key traits. The high proportion of genetic variance in this study indicates that selection under tissue culture conditions for cold tolerance in lentils will be effective. In addition, important traits such as electrolyte leakage, and fresh and dry weight of the shoot were severely affected by cold stress, which can probably be used as a selection criterion for cold tolerance in lentils. These results can be used in breeding programs to improve cold tolerance in lentils.
Mina Amani; Mohsen Sabzi-Nojadeh
Abstract
Objective: The increasing global population and the growing demand for medicinal plants in the pharmaceutical industry highlight the importance of active compounds derived from these plants across various sectors. This trend has led to a significant rise in the cultivation of medicinal plants, particularly ...
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Objective: The increasing global population and the growing demand for medicinal plants in the pharmaceutical industry highlight the importance of active compounds derived from these plants across various sectors. This trend has led to a significant rise in the cultivation of medicinal plants, particularly Moldavian balm (Dracocephalum moldavica L.), which has gained popularity worldwide. However, as the cultivation of Moldavian balm expands, it is likely to encounter abiotic stresses, particularly water deficit stress, during its growing season. Drought stress can severely affect plant health by disrupting physiological and metabolic functions. In this context, melatonin has emerged as a crucial regulator of plant biological responses, modulating various physiological processes and enhancing resilience to stress conditions. Therefore, considering the limited water resources in the country and the positive effects of melatonin on plants, as well as the medicinal importance of Moldavian balm, this research was conducted with the aim of investigating the effect of melatonin on improving the physiological properties of the medicinal plant Moldavian balm in greenhouse cultivation.
Method: In this study, we investigated the effects of different concentrations of melatonin (such as control, 50, and 100 micromolar) on the physiological characteristics of Moldavian balm subjected to varying levels of drought stress (including 25%, 50%, 75%, and 100% of field capacity). The experimental design employed was a factorial arrangement in a completely randomized block design with three replications, allowing for robust statistical analysis of the results. This experiment was conducted in the greenhouse and laboratory of the Faculty of Agriculture and Natural Resources, Ahar, University of Tabriz.
Results: The application of 100 µM melatonin significantly enhanced the levels of photosynthetic pigments in Moldavian balm. This increase is crucial as chlorophyll and carotenoids are vital for photosynthesis, enabling plants to convert light energy into chemical energy efficiently. Enhanced photosynthetic activity directly correlates with improved growth and productivity, especially under stress conditions. The study revealed that melatonin treatment, particularly at the 100 µM concentration, led to a marked increase in secondary metabolites, including phenolic compounds and flavonoids. These compounds are known for their role in plant defense mechanisms, providing protection against environmental stressors, including drought. The highest recorded levels of phenol (51.952 mg gallic acid g-1 FW) and flavonoid (11.424 mg quercetin g-1 FW) were observed in the melatonin-treated plants, indicating enhanced protective capabilities. The activity of antioxidant enzymes, specifically phenylalanine ammonia-lyase, was significantly elevated in the melatonin-treated plants. This enzyme plays a crucial role in the biosynthesis of phenolic compounds, which are instrumental in combating oxidative stress. The recorded activity of 17.84 µM cinnamic acid min. mg-1 protein under severe drought conditions (25% of field capacity) underscores the protective role of melatonin in enhancing plant resilience.
Conclusion:The findings of this study clearly demonstrate that melatonin can serve as an effective agent in reducing the damage caused by drought stress in Moldavian balm. By enhancing photosynthetic efficiency, increasing secondary metabolite production, and boosting antioxidant enzyme activity, melatonin not only helps plants withstand unfavorable environmental conditions but also improves their overall quality and yield.
Mehdi Joudi; Asghar Mehraban
Abstract
Objective: This research was carried out to study the potential of photoassimilates accumulation and remobilization in the stem internodes of rainfed barley cultivars grown under regions with different climates.
Methods: Eight barley cultivars (four two-rowed and four six-rowed cultivars) were cultivated ...
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Objective: This research was carried out to study the potential of photoassimilates accumulation and remobilization in the stem internodes of rainfed barley cultivars grown under regions with different climates.
Methods: Eight barley cultivars (four two-rowed and four six-rowed cultivars) were cultivated under rainfed conditions in Meshginshahr (Mediterranean region with cold winter) and Jafarabad-Moghan (semi-tropical region with semi-cold winter) during 2023-2024 growing season. Photoasimilate accumulation and remobilization were measured in the stem internodes (peduncle, penultimate, and lower internodes) based on dry weight changes.
Results: Experimental sites were different in terms of climate. At Meshginshahr site, the high amount of precipitation and the low average temperature caused the growing season to be longer compared to Moghan site. The length of upper internodes (peduncle and penultimate) was higher in Meshginshahr than Moghan. On the other hand, the lower internodes formed a higher proportion of the stem length at Moghan region. The maximum weight of peduncle, penultimate and lower internodes was attained in Meshginshahr condition at 18, 18 and 15 days after anthesis, and in Moghan region at 4, 4 and 4 days after anthesis, respectively. The maximum weight of internodes (accumulated photoassimilates), the amount of reserves remobilization as well as the amount of grain yield per stem were higher in Meshginshahr than Moghan. Large variations were found for morphologic, physiologic, and agronomic traits among tested cultivars. In general, cultivar × location interaction was not significant for maximum weight and maximum specific weight of internodes and stem. Althought the values of these traits varied with location, the rank of cultivars for these variables remaned nealy unchanged. The highest values of internode’s weight and specific weight belonged to Barzin and Jolgeh cultivars at Meshginshhar and Moghan regions. Cultivar × location interaction was significant for internodes and stem’s remobilization. The change of location, on the one hand, altered the values of these traits and, on the other hand, changed the ranking of cultivars for them. Jolgeh and Barzin at Meshginshahr and Barzin and Oxin at Moghan region showed the highest values of internode’s cumulative remobilization.
Conclusion: In the current study, the amount of accumulation and remobilization was highest in the lower internodes under both Meshginshar and Moghan regions. Therefore, in order to reach their potential for accumulating the dry matter at the beginning of spring as well as to be a major source of dry matter remobilization at the end of growing season, the lower internodes are expected to have appropriate lengths, weights and specific weights.