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Janusz J. Zwiazek - One of the best experts on this subject based on the ideXlab platform.
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stable expression of aquaporins and hypoxia responsive genes in Adventitious Roots are linked to maintaining hydraulic conductance in tobacco nicotiana tabacum exposed to root hypoxia
PLOS ONE, 2019Co-Authors: Xiangfeng Tan, Janusz J. ZwiazekAbstract:Formation of Adventitious Roots in plants is a common response to hypoxia caused by flooding. In tobacco, after one week of root hypoxia treatment, plants produced twice as many Adventitious Roots as the aerated plants, but their maximum length was reduced. Hypoxia severely reduced net photosynthesis, transpiration rates, and photosynthetic light responses. Relative transcript abundance of the examined aquaporins in lateral Roots was reduced by hypoxia, but in Adventitious Roots it remained unchanged. This apparent lack of an effect of root hypoxia on the aquaporin expression likely contributed to maintenance of high hydraulic conductance in Adventitious Roots. Lateral Roots had lower porosity compared with Adventitious Roots and the expression of the ACS (1-aminocyclopropane-1-carboxylate synthase) gene was induced in hypoxic lateral Roots, but not in Adventitious Roots, providing additional evidence that lateral Roots were more affected by hypoxia compared with Adventitious Roots. ATP concentrations were markedly lower in both hypoxic lateral and Adventitious Roots compared with aerated Roots, while the expression of fermentation-related genes, ADH1 (alcohol dehydrogenase 1) and PDC1 (pyruvate decarboxylase 1), was higher in lateral Roots compared with Adventitious Roots. Since root porosity was greater in Adventitious compared with lateral Roots, the results suggest that the improved O2 delivery and stable root aquaporin expression in Adventitious Roots were likely the key factors helping flooded tobacco plants maintain high rates of root hydraulic conductance and, consequently, shoot gas exchange.
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Role of Adventitious Roots in water relations of tamarack ( Larix laricina ) seedlings exposed to flooding
BMC Plant Biology, 2012Co-Authors: Mónica Calvo-polanco, Jorge Señorans, Janusz J. ZwiazekAbstract:Background Flooding reduces supply of oxygen to the Roots affecting plant water uptake. Some flooding-tolerant tree species including tamarack (Larix laricina (Du Roi) K. Koch) produce Adventitious Roots in response to flooding. These Roots were reported to have higher hydraulic conductivity under flooding conditions compared with non-Adventitious Roots. In the present study, we examined structural and functional modifications in Adventitious Roots of tamarack seedlings to explain their flooding tolerance.
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role of Adventitious Roots in water relations of tamarack larix laricina seedlings exposed to flooding
BMC Plant Biology, 2012Co-Authors: Monica Calvopolanco, Jorge Señorans, Janusz J. ZwiazekAbstract:Flooding reduces supply of oxygen to the Roots affecting plant water uptake. Some flooding-tolerant tree species including tamarack (Larix laricina (Du Roi) K. Koch) produce Adventitious Roots in response to flooding. These Roots were reported to have higher hydraulic conductivity under flooding conditions compared with non-Adventitious Roots. In the present study, we examined structural and functional modifications in Adventitious Roots of tamarack seedlings to explain their flooding tolerance. Seedlings were subjected to the flooding treatment for six months, which resulted in an almost complete disintegration of the existing root system and its replacement with Adventitious Roots. We compared gas exchange parameters and water relations of flooded plants with the plants growing in well-drained soil and examined the root structures and root water transport properties. Although flooded seedlings had lower needle chlorophyll concentrations, their stomatal conductance, net photosynthesis rates and shoot water potentials were similar to non-flooded plants, indicative of flooding tolerance. Flooded Adventitious Roots had higher activation energy and a higher ratio of apoplastic to cell-to-cell water flow compared with non-flooded control Roots as determined with the 1-hydroxypirene 3,6,8-trisulfonic acid apoplastic tracer dye. The Adventitious Roots in flooded plants also exhibited retarded xylem and endodermal development and accumulated numerous starch grains in the cortex. Microscopic examination of root sections treated with the PIP1 and PIP2 antibodies revealed high immunoreactivity in the cortex of non-flooded Roots, as compared with flooded Roots. Structural modifications of Adventitious Roots suggest increased contribution of apoplastic bypass to water flow. The reduced dependence of Roots on the hypoxia-sensitive aquaporin-mediated water transport is likely among the main mechanisms allowing tamarack seedlings to maintain water balance and gas exchange under flooding conditions.
Keeyoeup Paek - One of the best experts on this subject based on the ideXlab platform.
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auxin affects on production of Adventitious Roots and secondary metabolites in echinacea angustifolia
The Korean Journal of Medicinal Crop Science, 2012Co-Authors: Young Se Jang, Hai Yan Cui, Eunjung Lee, Haewon Kim, Keeyoeup PaekAbstract:The production of Adventitious Roots derived from root explant of Echinacea angustifolia and its secondary metabolite content were assessed in different types and levels of auxin. The induction of Adventitious Roots from root explant cultured in Murashige and Skoog solid medium supplemented with 1.0 mg/L indole -3-butyric acid (IBA) attained highest as 20.87 mg fresh weight and 3.07 mg dry weight per culture but root suspension culture at the same concentration of IBA enhanced biomass production as 3.07 g fresh weight and 0.38 g per culture after 4 weeks in culture. 3.0 mg/L -naphthalene acetic acid (NAA) treatment had similar effect on root biomass production as 3.07 g fresh weight and 0.38 g per culture with liquid suspension culture, whereas Adventitious Roots exposed to over 3.0-5.0 mg/L IBA or 5.0 mg/L NAA were less responsive by reducing the number of Adventitious Roots and/or changing root morphology such as short and thick. The content of secondary metabolites such as phenolic, flavonoids and total caffeic acid in Adventitious Roots cultured on MS medium supplemented with 1.0 mg/L IBA were attained highest as 27.20, 9.60. 10.67 mg/g dry weight, respectively. Overall, the best production of root biomass and secondary metabolites were given by 1.0 mg/L IBA.
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Induction of Adventitious Roots of Echinacea pallida and accumulation of caffeic acid derivatives
Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica, 2012Co-Authors: Tao Huang, Xi-hua Cui, Keeyoeup PaekAbstract:OBJECTIVE To investigate the effect of auxins 2,4-D,IAA,IBA,NAA on induction of Adventitious Roots as well as that of IBA concentrations on the growth of Adventitious Roots and the accumulation of caffeic acid derivatives, with test-tube seedling leaves Echinacea pallida as the explant, and cultivate Adventitious Roots in bioreactors. RESULT 1.0 mg x L(-1) IBA was found the best for the induction of Adventitious Roots, with the numer of induced Adventitious Roots up to 22. 5 in each culture dish. Among different concentrations for suspension cultivation of IBA tested, 1.0 mg x L(-1) IBA was found the most suitable for the growth of Adventitious Roots and the accumulation of caffeic acid derivatives. In a 5 L balloon type bubble bioreactor, 8.98 g x L(-1) dry weight was achieved after one month, which was 2.05 times of 4.38 g x L(-1) dry weight cultivated in a triangular flask. The content of echinacoside cultivated in a bioreactor was 14.08 mg x g(-1) DW, which was 2.4 times of cultivated Roots. The contents of chlorogenic acid, chicoric acid and total caffeic acid derivatives were 4.0-25.6 times of ultivated Roots. CONCLUSION The study can provide high-quality biomedical drugs containing such caffeic acid derivatives as echinacoside for mass production of Echinacea purpurea medicines.
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Adventitious Roots induction of recalcitrant tropical woody plant, Eurycoma longifolia
2012Co-Authors: Sobri Hussein, Keeyoeup Paek, Anna Pick, Kiong Ling, Rusli Ibrahim, Kuala LumpurAbstract:Eurycoma longifolia is well known for its aphrodisiac and energy enhancing properties especially among the communities in Southeast Asia regions attributed to the bioactive compounds concentrated mainly in its tap root. Over-exploitation of the plants from the natural habitat has led to the shortage of the plant in the jungle. In this study, the effects of naphthaleneacetic acid (NAA), indole acetic acid (IAA) and indole butyric acid (IBA) at the concentrations of 0, 1, 3, 5 and 7 mg/L on Adventitious Roots induction from the leaf explants were tested on full strength Murashige and Skoog (MS) medium. The best auxin and the optimal concentration determined was NAA at 3 mg/L as measured in terms of percentage of explants forming Roots and the number of Roots formed per explant. In the study on sucrose concentrations, 3 mg/L of NAA-containing MS medium was supplemented with sucrose at 10, 30, 50 and 70 g/L. The results revealed that 50g/L sucrose that produced 3.2 Roots per explant was better than 30g/L in inducing Adventitious Roots. Further studies using different carbon sources revealed that glucose recorded the highest rooting percentage (42.2%) while sucrose gave the highest root number (3.0) per explant. This study reported the first successful Adventitious Roots induction of E. longifolia, which promise a high potential of large scale commercial production in bioreactor for the pharmaceutical industries.
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production of Adventitious Roots and secondary metabolites by hypericum perforatum l in a bioreactor
Bioresource Technology, 2010Co-Authors: Debasis Chakrabarty, Keeyoeup PaekAbstract:Abstract We investigated the effects of different concentrations of auxin and auxin/cytokinin combinations, inoculum sizes and Murashige and Skoog (MS) medium dilutions on biomass and accumulation of total phenols and flavonoids in Adventitious Roots of Hypericum perforatum . The optimized conditions for the shake flask culture growth and secondary metabolites production were 0.1 mg/l kinetin with 1 mg/l indole-3-butyric acid (IBA), an inoculum density of 6 g/l fresh weight (FW) and 1/2MS in the 5-week old cultures. By inoculating 6 g/l of Adventitious Roots into a 3-l balloon type bubble bioreactor (BTBB) containing l/2 MS medium supplemented with 0.1 mg/l kinetin with 1 mg/l IBA, 104.2 g/l Adventitious Roots were harvested containing 56.47 ± 0.22 mg/g dry weight (DW) total phenolics, 35.01 ± 1.26 mg/g DW flavonoids, 0.97 ± 0.06 mg/g DW chlorogenic acid and 1.389 ± 0.80 mg/g DW hypericin. The results of our study contribute to optimization and development of bioreactor technology for Adventitious root cultures of H. perforatum for the production of hypericin.
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Cryopreservation of Panax ginseng Adventitious Roots
Journal of Plant Biology, 2009Co-Authors: Oh Suk Young, Elena Popova, Eun Joo Hahn, Keeyoeup PaekAbstract:We tested desiccation and/or vitrification procedures to cryopreserve the Adventitious Roots of Panax ginseng, the source of commercially produced ginsenosides. When only desiccation was applied, the post-freeze survival of 3- to 4-mm root tips was
Jorge Señorans - One of the best experts on this subject based on the ideXlab platform.
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Role of Adventitious Roots in water relations of tamarack ( Larix laricina ) seedlings exposed to flooding
BMC Plant Biology, 2012Co-Authors: Mónica Calvo-polanco, Jorge Señorans, Janusz J. ZwiazekAbstract:Background Flooding reduces supply of oxygen to the Roots affecting plant water uptake. Some flooding-tolerant tree species including tamarack (Larix laricina (Du Roi) K. Koch) produce Adventitious Roots in response to flooding. These Roots were reported to have higher hydraulic conductivity under flooding conditions compared with non-Adventitious Roots. In the present study, we examined structural and functional modifications in Adventitious Roots of tamarack seedlings to explain their flooding tolerance.
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role of Adventitious Roots in water relations of tamarack larix laricina seedlings exposed to flooding
BMC Plant Biology, 2012Co-Authors: Monica Calvopolanco, Jorge Señorans, Janusz J. ZwiazekAbstract:Flooding reduces supply of oxygen to the Roots affecting plant water uptake. Some flooding-tolerant tree species including tamarack (Larix laricina (Du Roi) K. Koch) produce Adventitious Roots in response to flooding. These Roots were reported to have higher hydraulic conductivity under flooding conditions compared with non-Adventitious Roots. In the present study, we examined structural and functional modifications in Adventitious Roots of tamarack seedlings to explain their flooding tolerance. Seedlings were subjected to the flooding treatment for six months, which resulted in an almost complete disintegration of the existing root system and its replacement with Adventitious Roots. We compared gas exchange parameters and water relations of flooded plants with the plants growing in well-drained soil and examined the root structures and root water transport properties. Although flooded seedlings had lower needle chlorophyll concentrations, their stomatal conductance, net photosynthesis rates and shoot water potentials were similar to non-flooded plants, indicative of flooding tolerance. Flooded Adventitious Roots had higher activation energy and a higher ratio of apoplastic to cell-to-cell water flow compared with non-flooded control Roots as determined with the 1-hydroxypirene 3,6,8-trisulfonic acid apoplastic tracer dye. The Adventitious Roots in flooded plants also exhibited retarded xylem and endodermal development and accumulated numerous starch grains in the cortex. Microscopic examination of root sections treated with the PIP1 and PIP2 antibodies revealed high immunoreactivity in the cortex of non-flooded Roots, as compared with flooded Roots. Structural modifications of Adventitious Roots suggest increased contribution of apoplastic bypass to water flow. The reduced dependence of Roots on the hypoxia-sensitive aquaporin-mediated water transport is likely among the main mechanisms allowing tamarack seedlings to maintain water balance and gas exchange under flooding conditions.
Monica Calvopolanco - One of the best experts on this subject based on the ideXlab platform.
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role of Adventitious Roots in water relations of tamarack larix laricina seedlings exposed to flooding
BMC Plant Biology, 2012Co-Authors: Monica Calvopolanco, Jorge Señorans, Janusz J. ZwiazekAbstract:Flooding reduces supply of oxygen to the Roots affecting plant water uptake. Some flooding-tolerant tree species including tamarack (Larix laricina (Du Roi) K. Koch) produce Adventitious Roots in response to flooding. These Roots were reported to have higher hydraulic conductivity under flooding conditions compared with non-Adventitious Roots. In the present study, we examined structural and functional modifications in Adventitious Roots of tamarack seedlings to explain their flooding tolerance. Seedlings were subjected to the flooding treatment for six months, which resulted in an almost complete disintegration of the existing root system and its replacement with Adventitious Roots. We compared gas exchange parameters and water relations of flooded plants with the plants growing in well-drained soil and examined the root structures and root water transport properties. Although flooded seedlings had lower needle chlorophyll concentrations, their stomatal conductance, net photosynthesis rates and shoot water potentials were similar to non-flooded plants, indicative of flooding tolerance. Flooded Adventitious Roots had higher activation energy and a higher ratio of apoplastic to cell-to-cell water flow compared with non-flooded control Roots as determined with the 1-hydroxypirene 3,6,8-trisulfonic acid apoplastic tracer dye. The Adventitious Roots in flooded plants also exhibited retarded xylem and endodermal development and accumulated numerous starch grains in the cortex. Microscopic examination of root sections treated with the PIP1 and PIP2 antibodies revealed high immunoreactivity in the cortex of non-flooded Roots, as compared with flooded Roots. Structural modifications of Adventitious Roots suggest increased contribution of apoplastic bypass to water flow. The reduced dependence of Roots on the hypoxia-sensitive aquaporin-mediated water transport is likely among the main mechanisms allowing tamarack seedlings to maintain water balance and gas exchange under flooding conditions.
Mónica Calvo-polanco - One of the best experts on this subject based on the ideXlab platform.
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Role of Adventitious Roots in water relations of tamarack ( Larix laricina ) seedlings exposed to flooding
BMC Plant Biology, 2012Co-Authors: Mónica Calvo-polanco, Jorge Señorans, Janusz J. ZwiazekAbstract:Background Flooding reduces supply of oxygen to the Roots affecting plant water uptake. Some flooding-tolerant tree species including tamarack (Larix laricina (Du Roi) K. Koch) produce Adventitious Roots in response to flooding. These Roots were reported to have higher hydraulic conductivity under flooding conditions compared with non-Adventitious Roots. In the present study, we examined structural and functional modifications in Adventitious Roots of tamarack seedlings to explain their flooding tolerance.