Agriculture and horticulture
Mohammad Haghaninia; abdollah javanmard; Zahra Ghorbani; mohammad reza morshedloo; Karim Kakaei
Abstract
Background and Objective: In contemporary times, the importance of medicinal plants and their identification in advancing national, regional, and global objectives, such as achieving health, pharmaceutical self-sufficiency, fostering employment, and promoting economic development, ...
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Background and Objective: In contemporary times, the importance of medicinal plants and their identification in advancing national, regional, and global objectives, such as achieving health, pharmaceutical self-sufficiency, fostering employment, and promoting economic development, is indisputable. Mentha suaveolens × Mentha piperita, commonly referred to as grapefruit mint, is recognized as a valuable medicinal plant within the Lamiaceae family. Drought stands out as a major limiting factor for global plant growth, constituting the most prevalent environmental stressor that disrupts the balance between reactive oxygen species and antioxidant defense mechanisms, thereby inducing oxidative stress. Nanotechnology emerges as a modern approach with notable potential to enhance plant resilience against drought stress. Among various nanomaterials, carbon quantum dots, discovered in 2004, possess distinctive characteristics, including dimensions below 10 nanometers, reduced toxicity, and superior biocompatibility compared to metal-based alternatives, owing to their carbonaceous structure. Due to these unique attributes, carbon quantum dots have attracted significant research interest in recent years. Therefore, this study aimed to evaluate the effects of carbon quantum dots on the growth, yield, and essential oil composition of grapefruit mint (Mentha suaveolens × piperita) under drought stress conditions.Methodology: This research was conducted as a factorial experiment in a completely randomized design with four replications in pots during the spring and summer of 2023 at the research greenhouse of Maragheh University, East Azerbaijan, Iran. The first factor was irrigation at 90% of field capacity (FC) as control (normal irrigation), irrigation at 70% FC (moderate stress), and irrigation at 50% FC (severe stress). The second factor consisted of different levels of carbon quantum dots (0, 5, 10, 15, and 20 parts per million). Data collected from sampling were analyzed using SAS statistical software, and means were compared using the least significant difference (LSD) test at the 5% level.Results: Analysis of variance indicated that the effects of different irrigation regimes, fertilizer treatments, and their interaction on all measured traits were significant. The findings revealed that the application of 15 ppm carbon quantum dots under normal irrigation increased fresh weight, dry weight, chlorophyll a, and chlorophyll b contents by 110%, 86%, 184%, and 163%, respectively, compared to no CQD application under severe drought stress. Under moderate stress, the use of 15 ppm carbon quantum dots increased essential oil content by 135% and essential oil yield by 298% compared to severe stress without CQD. Furthermore, the highest linalyl acetate content was obtained with 15 ppm carbon quantum dots under 50% FC, showing a 50.1% increase compared to the control treatment. Similarly, the highest linalool content was recorded under normal irrigation with 10 ppm carbon quantum dots, representing a 67.4% increase compared to no CQD application under 50% FC. Moreover, under normal irrigation, 15 ppm carbon quantum dots reduced malondialdehyde and hydrogen peroxide contents by 51% and 58%, respectively, compared to no CQD application under severe stress. Additionally, under mild stress, 15 ppm carbon quantum dots enhanced the activity of superoxide dismutase, guaiacol peroxidase, and ascorbate peroxidase enzymes by 123%, 111%, and 72%, respectively, compared to no fertilizer application under normal conditions.Conclusion: The results indicate that applying 15 ppm carbon quantum dots can promote growth by modulating secondary metabolites and strengthening defense mechanisms through the activation of antioxidant enzymes and increasing the accumulation of osmolytes such as proline and total soluble sugars, thereby reducing malondialdehyde and hydrogen peroxide levels. This enhancement in grapefruit mint plants contributes to improved drought resilience, ultimately enhancing both the quantity and quality of the essential oil.
H. Fatemi; B. Esmaielpour; A.A Soltani-Toolarood; A. Nematolah Zadeh
Abstract
Silicon (Si) is the second most abundant element in the earth crust. Silicon has been shown to ameliorate the adverse effects of heavy metals on plants. This research was aimed to investigate the effects of silicon nano-fertilizer nutrition on growth and physiological characteristics of coriander (Coriandrum ...
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Silicon (Si) is the second most abundant element in the earth crust. Silicon has been shown to ameliorate the adverse effects of heavy metals on plants. This research was aimed to investigate the effects of silicon nano-fertilizer nutrition on growth and physiological characteristics of coriander (Coriandrum sativum L.) under lead stress. The study was conducted in a factorial experiment based on a completely randomized design with four replications in the research greenhouse of Mohaghegh Ardabili University during 2016. Experimental treatments included soil contamination by PbCl2 (0, 500, 1000 and 1500 mg/kg soil) and foliar spraying with silicon nano-fertilizer (0, 1.5 and 3 mM). Morphological studied traits including plant height, leaf number and area, fresh and dry weight of root and plant, root and stem diameter, physiological parameters such as photosynthetic pigments, electrolyte leakage, relative water contents, proline, carbohydrates, phenol, antioxidants were measured. Results indicated that lead stress reduced the morphological characteristics such as plant height, plant fresh and dry weight, and stem and root diameter, so that the increased content of lead led to decrease of plant dry weight, root weight, root and stem diameter, root length, plant height, leaf area and dry weight up to 57, 50, 20, 41, 15, 42 and 25%, respectively. Foliar spraying with silicon (3mM) led to improve most of morphological traits of coriander. The content of chlorophyll a, chlorophyll b, total chlorophyll, carotenoid and carbohydrate in leaves was increased with increasing lead concentration in soil. However, silicon foliar spraying improved these traits under lead stress. Proline, phenol, flavonoid and antioxidant capacity were significantly increased with increasing concentration of lead up to 1500mg/kg. In general, it can be concluded that the use of silicon nanoparticles for coriander can reduce the negative effects of lead stress to a satisfactory level.
H. Mousavi; N. Mahdi Nezhad; B. Fakheri; M. Majdi; F. Heidari
Abstract
To investigate the effects of nano-chelate spraying of Iron, chemical -synthesis and green-synthesis silver nanoparticles on the expression of two genes, germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes which are involved in the parthenolide biosynthesis pathway of Tanacetum parthenium ...
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To investigate the effects of nano-chelate spraying of Iron, chemical -synthesis and green-synthesis silver nanoparticles on the expression of two genes, germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes which are involved in the parthenolide biosynthesis pathway of Tanacetum parthenium L., a factorial experiment based on randomized complete block design was conducted with three replications. The experiment took place in the greenhouse of Zabol University in Iran. At first, the total RNA from samples of leaves, and then the synthesis of cDNA were extracted. Afterward, Real Time PCR analysis was used to determine gene expression patterns. Parthenolide concentration was measured by high-performance liquid chromatography (HPLC). The analysis of the data was conducted by SAS software, and there was a significant increase in the expressions of both germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes of treated plants with green-synthesis silver nanoparticles in compare with the control plants, and some plants which were treated by chemical- synthesis silver nanoparticles and nano-chelate of Iron. Furthermore, the maximum expressions of both germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes were identified in groups of plants which were under the influence of drought stress, or were treated by green-synthesis silver nanoparticles. A positive relation was seen between the expressions of germacrene A synthase genes (TpGAS) and parthenolide synthase (TpPTS) genes with the amount of parthenolide itself. It can be concluded that green-synthesis silver nanoparticles and water deficit stress can cause an increase on the expressions of parthenolide and germacrene A synthase genes, and as result of that, cause an increase on parthenolide production of Tanacetum parthenium.
