• Korean Journal of Microbiology
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• v.51 no.1
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• pp.14-20
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• 2015

Coastal plant species, Plantago camtschatica Cham. native to the coastal region of the East Sea were sampled and then morphologically different 20 endophytic fungal strains were purely isolated. Phylogenetic analysis of isolates was done by the Bayesian program based on sequenced internal transcribed spacer (ITS-rDNA) region. Culture filtrates of each of 20 isolates were treated to Waito-c rice (WR) seedlings for verifying plant growth-promoting activity, respectively. As the results, E/PC/10/1 strain showed the highest plant growth-promoting activity among them. The culture filtrate of the strain E/PC/10/1 was revealed as containing gibberellins ($GA_1$, $GA_3$, $GA_4$) by using HPLC, and gas GC/MS with selected ion monitoring (SIM). Finally, this strain was identified as novel Penicillium spinulosum species that producing new GAs with microscopic observation and further molecular analysis with beta-tubulin gene sequence.

• Journal of Life Science
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• v.27 no.11
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• pp.1233-1244
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• 2017

CDPKs have pivotal roles in plant $Ca^{2+}$-mediated transduction signaling. A total of 29 CDPK genes have been identified in rice (Oryza sativa L.), but their key functions have not been completely noted. This study focused on the OsCPK11 gene, which has not been studied, to determine its functional characteristics. A study of tissue-specific expressions revealed that the OsCPK11 gene is expressed in young leaves, mature leaves and flowers of rice. An expression of the gene was also confirmed in gibberellin-treated aleurone layers of rice. Regarding the phenotypic characteristics of Tos17-inserted OsCPK11 mutants, the heights of the mutants were not distinguishable from the heights of wild type plants, but the number of caryopses and the caryopses' weights were significantly statistically different. In addition, many grains of the mutants had white belly materials in their endosperm. The cDNA of the OsCPK11 was cloned, and an OsCPK11 protein of about 60.5 kD was obtained by using a GST affinity chromatography and an SDS-PAGE. An analysis of the amino-acid sequence of the protein indicated that the OsCPK11 protein has the structural characteristics of typical CDPKs. The results provided useful information about the functions of the OsCPK11 gene and further noted the roles CDPKs have in $Ca^{2+}$-mediated signaling in plants.

• Journal of Life Science
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• v.22 no.12
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• pp.1718-1723
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• 2012

Ten endophytic fungi with different colony morphologies were isolated from the roots of Suaeda japonica Makino growing naturally in Suncheon Bay. Plant growth promotion was verified by treating waito-c rice seedlings with culture filtrates from the endophytic fungi. The bioassays showed that the Sj/7/4 fungal strain induced effective growth promotion in the seedlings. The gibberellins (GA) produced by fungal strain Sj/7/4 were analyzed by gas chromatography /mass spectroscopy with selected ion monitoring (GC/MS SIM). The culture filtrate of Sj/7/4 fungal strain was confirmed to contain $GA_4$ through quantitative analysis. The Sj/7/4 fungal strain was identified to determine the internal transcribed spacer (ITS) regions with universal primers ITS-1 and ITS-4 by using polymerase chain reactions (PCR). Molecular analysis of the Sj/7/4 fungal strain showed high similarity to Fusarium solani. The Sj/7/4 fungal strain isolated from the root of S. japonica was therefore designated as F. solani Sj/7/4.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.750-756
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• 2010

This study was performed to investigate the role of phytohormones in the bulbing of garlic in order to assess the yield and quality. The effect on endogenous plant hormones such as gibberellin (GA) content was also examined during growth stage i.e. clove differentiation to bulbing in garlic. More than 18 gibberellins in garlic were identified with extensive gas chromatograph-mass spectrometry-selected ion monitoring (GC-MS-SIM) quantitative analysis. The results showed that GAs were biosynthesized by both non C-13 hydroxylation pathway (NCH) and early C-13 hydroxylation pathway (ECH) in garlic plant. It was also revealed that NCH pathway leading to synthesis of bioactive $GA_4$ was the more prominent GA biosynthesis pathway than ECH pathway in which bioactive $GA_1$ was synthesized. Total GAs level was gradually increased from clove differentiation to bulbing and later decreased, which portrays the active role of GA in differentiation. The biosynthesis ratio of bioactive $GA_4$ and $GA_1$ concentration was similar to that of total GAs content, which was closely related with bulb development in garlic.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.893-902
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• 2011

Endophytic fungi are little known for their role in gibberellins (GAs) synthesis and abiotic stress resistance in crop plants. We isolated 10 endophytes from the roots of field-grown soybean and screened their culture filtrates (CF) on the GAs biosynthesis mutant rice line - Waito-C. CF bioassay showed that endophyte GMH-1B significantly promoted the growth of Waito-C compared with controls. GMH-1B was identified as Penicillium minioluteum LHL09 on the basis of ITS regions rDNA sequence homology and phylogenetic analyses. GC/MS-SIM analysis of CF of P. minioluteum revealed the presence of bioactive $GA_4$ and $GA_7$. In endophyte-soybean plant interaction, P. minioluteum association significantly promoted growth characteristics (shoot length, shoot fresh and dry biomasses, chlorophyll content, and leaf area) and nitrogen assimilation, with and without sodium chloride (NaCl)-induced salinity (70 and 140 mM) stress, as compared with control. Field-emission scanning electron microcopy showed active colonization of endophyte with host plants before and after stress treatments. In response to salinity stress, low endogenous abscisic acid and high salicylic acid accumulation in endophyte-associated plants elucidated the stress mitigation by P. minioluteum. The endophytic fungal symbiosis of P. minioluteum also increased the daidzein and genistein contents in the soybean as compared with control plants, under salt stress. Thus, P. minioluteum ameliorated the adverse effects of abiotic salinity stress and rescued soybean plant growth by influencing biosynthesis of the plant's hormones and flavonoids.

• Mycobiology
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• v.43 no.4
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• pp.373-383
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• 2015

Five halophytic plant species, Suaeda maritima, Limonium tetragonum, Suaeda australis, Phragmites australis, and Suaeda glauca Bunge, which are native to the Muan salt marsh of South Korea, were examined for fungal endophytes by sequencing the internal transcribed spacer (ITS) region containing ITS1, 5.8S rRNA, and ITS2. In total, 160 endophytic fungal strains were isolated and identified from the roots of the 5 plant species. Taxonomically, all 160 strains belonged to the phyla Ascomycota, Basidiomycota, and Zygomycota. The most dominant genus was Fusarium, followed by the genera Penicillium and Alternaria. Subsequently, using 5 statistical methods, the diversity indices of the endophytes were determined at genus level. Among these halophytic plants, P. australis was found to host the greatest diversity of endophytic fungi. Culture filtrates of endophytic fungi were treated to Waito-C rice seedlings for plant growth-promoting effects. The fungal strain Su-3-4-3 isolated from S. glauca Bunge provide the maximum plant length (20.1 cm) in comparison with wild-type Gibberella fujikuroi (19.6 cm). Consequently, chromatographic analysis of the culture filtrate of Su-3-4-3 showed the presence of physiologically active gibberellins, $GA_1$ (0.465 ng/mL), $GA_3$ (1.808 ng/mL) along with other physiologically inactive $GA_9$ (0.054 ng/mL) and $GA_{24}$ (0.044 ng/mL). The fungal isolate Su-3-4-3 was identified as Talaromyces pinophilus.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.463-470
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• 2012

As the advanced seeding technology through use of plug tray for good cultivation of seeds was propagated along with the expansion and development of horticultural industry, the use of bed soils as growing medium has recently been increased. In this study, the effects of the four clay minerals such as illite, phyllite, zeolite, and bentonite on the early growth of red pepper in the bed soil were investigated. Furthermore, proteome analysis for the leaf and stem samples of red pepper treated with only illite was performed. Of the seedling cultured, the healthy and regular size seeds were selected and cultivated in the pots, after they were treated with four clay minerals. The experiment was performed during the whole six weeks in the glasshouse of the Chungbuk National University. The growth lengths, fresh and dry weights of red pepper were significantly higher in the treatments of illite, phyllite, zeolite, and bentonite than in the control. In addition, the uptake of $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were higher in the treatment of illite, phyllite, zeolite, and bentonite than in the control. The 2-DE patterns for the red pepper by the applications of illite, phyllite, zeolite, and bentonite were similar to each other. Therefore, compared to the samples of control, the proteome analysis for the samples of red pepper treated by only illite were performed. Proteome analysis for red pepper showed that plastid fructose-1, 6-bisphosphate aldolase class 1, aldolase, and glyceraldehydes 3-phosphate dehydrogenase, all of which were involved in the energy metabolism, were highly expressed in leaf tissue by illite treatment. In stem tissue, NAD-dependent formate dehydrogenase involved in energy metabolism, potassium transport protein, and GIA/RGA-like gibberellins response modulator were highly expressed. Based on the results obtained from the proteome analysis, it appears that the proteins specifically and differentially expressed on the illite treatment may be involved in the enhanced growth of red pepper. The identification of some proteins involved in the response of vegetable crops to the treatment of clay mineral can provide new insights that can lead to a better elucidation and understanding of mechanism on their molecular basis.