Elham Harati; Seyyed Gholamreza Moosavi; Fatemeh Nakhaei; Mohamad Javad Seghatoleslami
Abstract
Seed germination is the first and most sensitive developmental stage in the plant life cycle and the key process in seedling emergence. On the other hand, one of the major barriers to optimum use of medicinal plants outside the natural habitat is limited level of seed germination and seed dormancy. Hence ...
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Seed germination is the first and most sensitive developmental stage in the plant life cycle and the key process in seedling emergence. On the other hand, one of the major barriers to optimum use of medicinal plants outside the natural habitat is limited level of seed germination and seed dormancy. Hence in order to find the best priming and temperature treatment to dormancy breaking and seed germination of medicinal plant seed Pulicaria gnaphalodes (Vent.) Boiss a factorial experiment based on the completely randomized design with four replications and two factors was conducted in Islamic Azad University, Birjand branch in 2017. The first factor of priming type is 11 levels included in potassium nitrate 2% treatment at two times of 24 and 48 hours, gibberellic acid (0, 250 and 500 mg/ l) at two times of 24 and 48 hours, and stratification (7, 14 and 21 days). The second factor was temperature at three levels (15, 20 and 25 °c). The results showed that highest germination rate and percent germination were related to stratification at 7 and 21 days at 25 °c and maximum seedling length, plumule length, radicle length, radicle/plumule length ratio, wet weight of seedling, dry weight of seedling, percent germination, germination rate, longitudinal index seed vigor, weight index seed vigor related to 21 days wet temperature and 15°c. Therefore, 21 days stratification and temperatures of 15 and 25 °c were the best priming and temperature treatments to dormancy breaking and seed germination of medicinal plant seed Pulicaria gnaphalodes.
Javad Tabatabaeian; Azam Kadkhodaie
Abstract
Mountain celery with scientific name of Kelussia odoratissima Mozaff is one of native medicinal plants of Iran that is an endangered species due to illegal removal. Present study was carried out to find the suitable treatment for stimulating germination of seeds this plant. A factorial experiment based ...
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Mountain celery with scientific name of Kelussia odoratissima Mozaff is one of native medicinal plants of Iran that is an endangered species due to illegal removal. Present study was carried out to find the suitable treatment for stimulating germination of seeds this plant. A factorial experiment based on a completely randomized design with four replications was used. Stratification (4 ̊C for 0, 4, and 8 weeks), 500 ppm solutions of Gibberellin (GA), Benzyl adenine (BA), Naphthalene acetic acid (NAA), Indole butyric acid (IBA) and combinations of these hormones as follows: (GA+IBA), (GA+ NAA), (GA+BA), (IBA+NAA), (IBA+BA), (NAA+BA), (GA+ IBA+NAA), (GA+ IBA+BA), (GA+NAA+BA), (IBA+NAA+BA), (GA+ IBA +NAA+BA) were the treatments. The results showed that Stratification or hormonal treatments alone increased germination parameters, however, 8 weeks stratification and GA were the most effective treatments. The highest germination percent and duration were obtained in GA, BA, GA+IBA+IBA and IBA after eight weeks of stratification at 4 ̊C due to treatments interaction suggesting that seeds of this species has physiological dormancy. There was no synergic effect between hormonal treatments. The results showed that mountain celery had physiological dormancy and treatments with the greatest degree of success in breaking dormancy were GA, BA, GA+IBA+BA, BA and IBA under 8 weeks stratification.
Abstract
Given that the seed germination of Chinese parasol tree (Firmiana simplex L.) and hence its propagation is experiencing difficulties, therefore, this study investigates the factors limiting seed germination of mentioned tree and how to troubleshoot them are discussed. This experiment was conducted in ...
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Given that the seed germination of Chinese parasol tree (Firmiana simplex L.) and hence its propagation is experiencing difficulties, therefore, this study investigates the factors limiting seed germination of mentioned tree and how to troubleshoot them are discussed. This experiment was conducted in 2014 in a completely randomized design with a factorial arrangement with three replications in the laboratory of Horticultural Science Department, Gorgan University of Agricultural Sciences and Natural Resources of Iran. In order to remove physical dormancy (impermeable seed coat) mechanical scarification treatments with fine sand (shaking seeds and building sand for 5, 10 and 15 minutes), hot water (70 °C) and acid (treatments of seeds with solution of concentrated sulfuric acid for 1, 5 and 10 minutes and then rinse by tap water for 20 minutes) were used. Moreover to remove the physiological dormancy, stratification of seeds were applied for 30, 45 and 60 days in 3-6oC. The results showed that the highest percentage of seed germination was related to scarification by sand (78%) for 15 minutes and stratification for 30 days. The lowest seed germination rate among all treatments was related to control (4.6%). In overall, it can be concluded from various treatments which used to break dormancy in seeds of Firmiana simplex, it is clear that the seeds of mentioned tree include dual seed dormancy, including seed coat and embryo dormancy. The results also showed seedling establishment of 86.6 % related to combination of scarification and stratification in the mentioned treatment has been much higher than other treatments, specially control (without scarification).
