Negar Saemi; Mohammad Javad Nazarideljou; Nabi Khezri Nezhad
Abstract
This experiment was conducted to evaluate the effects of Ajowan's (Carum copticum) essential oil as a natural and non-chemical fungicide on flower longevity and gray mold infection as the most important agent of rose postharvest losses. Different essential oil concentrations of Ajowan (0, 300 600 and ...
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This experiment was conducted to evaluate the effects of Ajowan's (Carum copticum) essential oil as a natural and non-chemical fungicide on flower longevity and gray mold infection as the most important agent of rose postharvest losses. Different essential oil concentrations of Ajowan (0, 300 600 and 900 µL/L) applied as a postharvest foliar application on rose cut flowers (Rosa × hybrida cv. Angelina) which inoculated with gray mold fungus compared to the control (non-contaminated). Based on the results, enzymatic antioxidant capacity (CAT and POD), lipid peroxidation, vase life and gray mold contamination were affected significantly by gray mold infection and foliar application of Ajowan essential oil. According to the results, the minimum gray mold infection was observed at the highest essential oil level 900 µL/L. The highest flower vase life of roses which were inoculated by gray mold was observed at 600 µL/L; while maximum flower vase life was observed at the same concentration but in non-inoculated flowers by gray mold (control plants). The results of the present experiment led to conclude that increasing of flower longevity of infected roses by gray mold under Ajowan's essential oil was achieved because of lipid peroxidation reduction and ion leakage as well as a consequence of antioxidant activity which has been happened under essential oil treatments.
Fariba Amini; Shiva Shariat zade; Mehri Askary
Abstract
To study the effects of 24-epibrassinolode on improving germination parameters and seedling growth of typical American eggplant under chilling stress, an experiment with four concentrations of 24-epibrassinolode (0, 0.5, 1 and 2 µM) in completely randomized design in factorial form with three replicates ...
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To study the effects of 24-epibrassinolode on improving germination parameters and seedling growth of typical American eggplant under chilling stress, an experiment with four concentrations of 24-epibrassinolode (0, 0.5, 1 and 2 µM) in completely randomized design in factorial form with three replicates were performed in plant physiology lab of Arak University at 1391. Eggplant seeds were soaked in different concentrations of 24-epibrassinolode for 48 h and then moved to plate. Three plates each containing 20 seeds were considered as replications for each treatment. After planting the seeds, plated were divided into two groups. One group was transferred to an incubator with 16/8 -hour light/dark photoperiod (25 ± 1°C temperatures) and other group exposed to 4°C temperature for 4 days then transferred to the incubator. The results showed that 24-epibrassinolid had a great effect on the germination parameters, length of root and shoot, fresh and dry weights of root and shoot in both control and stress conditions. The increase of lipid peroxidation and membrane penetration that observed in chilling stress, indicated a significant decrease in treatment with 24-epibrassinolide. 1 μM concentration was the most effective concentration than others. In plants under chilling stress and 1 μM of 24-epibrassinolide, lipid peroxidation and membrane penetration decreased 28.30 and 37.89 percent, respectively.
Rouhollah Karimi; Ahmad Ershadi; Mahmoud Esna-Ashari; Masoud Mashhadi Akbar Boojar
Abstract
Screening of native cultivars and understanding of the mechanisms involved in cold hardiness in grapevines is needed to match cultivars appropriately with growing sites and aid in breeding and selecting cultivars with improved freezing tolerance. In this study cold hardiness of fifteen grapevine (Vitis ...
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Screening of native cultivars and understanding of the mechanisms involved in cold hardiness in grapevines is needed to match cultivars appropriately with growing sites and aid in breeding and selecting cultivars with improved freezing tolerance. In this study cold hardiness of fifteen grapevine (Vitis vinifera L.) cultivars were evaluated using tetrazolium stain test and post freezing budbreak assays during six months from acclimation till deacclimation stages. Moreover, seasonal changes pattern in soluble proteins, total phenol and Malondialdehyde (MDA) of buds were measured during this period. Significant differences (P≤0.01) were found among cold hardiness of cultivars in all stages. ‘Bidaneh Ghermez’ and ‘Khalili’ (LT50= -22 and -22.6 ºC in respectively) were the hardiest ‘Ruby’ and ‘Perlette’ (LT50= -16.1 and –16.9 ºC in respectively) were the least hardy cultivars in January. Soluble proteins and total phenol concentrations of buds increased during cold acclimation from November to January then decreased in March. The concentration of these compounds was higher in cold hardy such as ‘Bidaneh Ghermez’ and ‘Khalili’ cultivars than least hardy ones, indicating the positive relationship of these compounds with freezing tolerance. The measured MDA in onset and end of dormancy period was lower than its concentration in deep dormancy in January. Lower MDA concentration was found with cold hardy cultivars ‘Khalili’ and ‘Bidane Ghermez’ in comparison with cold sensitive cultivars, ‘Perlette’ and ‘Yaquti’. Our results indicated that high accumulation of soluble proteins and total phenol in cold hardy cultivars resulted in improved membrane stability and freezing tolerance.