• The Plant Pathology Journal
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• v.31 no.3
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• pp.310-315
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• 2015

Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR) stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

• Korean Journal of Medicinal Crop Science
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• v.14 no.5
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• pp.293-298
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• 2006

Optimum culture conditions for high frequency plant regeneration from leaf explants of Kalanchoe daigremontiana Hamet &Perrier were established. Shoot regeneration was achieved from leaf explant cultures using MS medium supplemented with indole-3-acetic acid (IAA) and thidiazuron (TDZ) or benzyladenine (BA). Percent regeneration was influenced by plant growth regulators and source of explants. MS medium supplemented with TDZ (1.0 mg/l) and IAA (0.4 mg/l) was the most effective, providing shoot regeneration for 76.7 % of ex vitro leaf explants associated with a high number of shoots per explant (9.5 mean shoots per explant), whereas 100% shoot regeneration associated with 12.4 shoots per explant occurred from in vitro leaf explants on the same medium. Clusters of shoots were multiplied and elongated on MS medium containing several concentrations of BA. MS medium supplemented with 0.25 mg/l BA was proved as the most effective shoot elongation medium. Elongated shoots (2-3 cm) were rooted at 100% on half-strength MS medium. Rooted plantlets were then transferred to potting soil. Regenerated plants were established in the soil with 90% success.

• Korean Journal of Plant Resources
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• v.10 no.1
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• pp.86-93
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• 1997

In order to induce somatic embryogenesis from the stem explants and anther of Kalanchoe daigremontiana, the explants were cultured on MS medium supplemented with auxin (2,4-D, IAA, NAA) and/or cytokinin (BAP) for 8 weeks. Callus from explants was induced most efficiently on MS medium containing. 2.0mg/L NAA and 0.2mg/L BAP. Somatic embryogenesis in stem callus was formed by transfering embryogenic callus from induction media containing growth regulators to medium without growth regulators and then to the medium containing auxin and cytokinin (0.1 mg/L IAA and 1.0mg/L BAP). Callus formation occurred actively in the anthers at early uninucleate stage, and by low temperature pretreatment at $4^{\circ}C$ for 3days. Somatic embryogenesis from the anther callus was induced on MS medium containing 1.0mg/L NAA and 1.0mg/L BAP, 2.0mg/L NAA and 0.2mg/L BAP. The tetraploid of 5.4% was obtained among plants regenerated from anthers.

• Journal of Ecology and Environment
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• v.30 no.2
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• pp.187-193
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• 2007

Higher plants can be categorized as C3, C4 or CAM according to their photosynthetic pathways, and some succulent plants are known to shift their patterns of photosynthesis from C3 to CAM in response to environmental stresses such as salt treatment or water deficiency. To investigate fundamental photosynthetic patterns and the induction of pattern shifts (C3, CAM, C3-CAM etc.) as a result of environmental stresses, we measured the water content, diurnal changes in pH, net $CO_2$ exchange, transpiration rate, total ionic contents, and osmolality of Kalancoe daigremontiana, Sedum kamschaticum and Sedum sarmentosum which belong to Crassulaceae known as representative CAM plant, after 10 days of drought treatment. S. kamschaticum and S. sarmentosum did not show a significant difference in diurnal pH variation in the treatment and control conditions. However, the pH of drought-treated Kalancoe was low at night and high in the daytime, with a pH value between 4 and 5. Typical CAM plants display a net $CO_2$ exchange that increases at night and decreases in the daytime. Kalancoe displayed the predicted pattern. However, S. kamschaticum and S. sarmentosum showed a photosynthetic pattern more typical of C3 plants, and did not show changes in photosynthetic pattern under drought stress. Kalancoe also showed a transpiration rate typical for CAM pho-tosynthesis, whereas the transpiration rates of S. kamschaticum and S. sarmentosum were in the typical range for C3 photosynthesis. Kalancoe had high total ionic contents during the night, which decreased somewhat during the daytime, whereas S. kamschaticum and S. sarmentosum displayed the opposite pattern. This result is similar to the diurnal patterns of changes in pH in the three plant species, which suggests a relationship between pH and ionic contents. S. sarmentosum showed lower osmolality under drought stress than in the control condition, whereas the osmolality of Kalancoe and S. kamschaticum did not differ between conditions. S. sarmentosum may have maintained internal water content by lowering its osmolality and raising its total ionic contents. In conclusion, Kalancoe displayed the characteristic responses of a typical CAM plant, whereas S. kamschaticum and S. sarmentosum displayed aspects of the C3 photosynthetic pattern under drought conditions. These results suggest that S. kamschaticum and S. sarmentosum (Crassulacea) in Korea overcome drought stress by increasing solute and ionic contents internally rather than changing their photosynthetic pattern from C3 to CAM under drought stress.