Agriculture and horticulture
F. Salarpour Qhoraba; H. Farahbakhsh
Abstract
To investigate the effects of chitosan foliar application on the various physiological and biochemical (proline, protein, antioxidant enzymes, and percentage and essential oil yield) characteristics and dry matter yield of thyme (Thymus vulgaris L.) under drought stress conditions, a split-plot experiment ...
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To investigate the effects of chitosan foliar application on the various physiological and biochemical (proline, protein, antioxidant enzymes, and percentage and essential oil yield) characteristics and dry matter yield of thyme (Thymus vulgaris L.) under drought stress conditions, a split-plot experiment was conducted in a randomized complete block design with three replications in Lalehzar city, Bardsir county, Kerman province in 2019. The drought stress at four levels (35, 50, 65, and 80% of available moisture discharge) and the chitosan concentration at five levels (0, 0.2, 0.5, 1.0, and 1.5 gram chitosan per liter of acetic acid) were considered as the main and sub plots, respectively. The results showed that the drought stress increased proline, antioxidant enzymes, and percentage and essential oil yield and decreased the dry matter yield significantly. The proline, antioxidant enzymes, dry matter yield, and essential oil percentage increased significantly with increasing the chitosan concentration, which resulted in a significant increase in the essential oil yield as the most important quality index in thyme. The protein and gayacol peroxidase enzyme were not affected by chitosan foliar application. In general, the results of this research showed that the higher chitosan concentrations (1.5 gram chitosan per liter of acetic acid) were more effective in ameliorating the damages induced by the drought stress and achieving the higher yield.
F. Salarpour; H. Farahbakhsh
Abstract
Recently, the application of SA has increased to improve plants’ resistance to stresses such as drought. Hence to investigate SA effects on morphophysiological characteristics of Fennel (Foeniculum vulgare Mill.) under drought stress, a split plot experiment based on latin square design with three ...
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Recently, the application of SA has increased to improve plants’ resistance to stresses such as drought. Hence to investigate SA effects on morphophysiological characteristics of Fennel (Foeniculum vulgare Mill.) under drought stress, a split plot experiment based on latin square design with three replications was carried out at the research farm of Shahid Bahonar University of Kerman in 2012. Three levels of drought stress (50, 75 and 100% of field capacity) and three concentrations of SA (0, 0.5 and 1mM) were considered as main and sub-plot treatments, respectively. Foliar application of SA was performed at 3-to 4-leaf growth stage and before application of drought stress. Results showed that the drought stress reduced the number of fertile umbel/plant, the number of fertile umbellate/umbel, the number of grains/umbellate, relative water content, chlorophyll, carotenoids and grain yield, while increased electrolyte leakage when compared with control. Salicylic acid reduced electrolyte leakage, while increased the number of fertile umbel/plant, the number of fertile umbellate/umbel, the number of grains/umbellate, RWC, chlorophyll, carotenoids and grain yield when compared to control (No SA application). Interaction of drought stress × SA on the number of fertile umbel/plant, the number of fertile umbellate/umbel, RWC, carotenoids and grain yield was significant. Increasing photosynthetic pigments, RWC and decreasing electrolyte leakage indicates a reduction in oxidative damage and implies SA role in tolerance of fennel to drought stress.
