• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.285-294
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• 1999

Changes of chemico-physical properties and mturitiy during pig manure composting were analysed using three kinds of bulking agents with rice hull(T1), rice hull and extruding hull mixture (T2, 1:1, v/v), and extruding hull(T3). During composting process, temperature of T1, T2 and T3 were maintained over $50^{\circ}C$ for 31, 21, and 35 days respectively. Organic matter content of each treatment was decreased from 82.2%, 82.0%, and 82.8% to 70.5%, 68.9% and 69.7% and pH increased to 8.85, 9.91, and 8.80, respectively. Total nitrogen content of all treatments gradually decreased, but C/N ratio, phosphorous, and potassium content did not, show any changes during composting process. Both germination rate and early growth were tested using radish seeds for composting maturity. From those results, it was concluded that all treatments were stabilized after 45th day and extruding hull(T3) added compost was superior to others. The test of suppressive effect showed that all treatment have no effect against Fusarium oxysporum, Alternaria altemata, Botrytis cinerea. Compost supplemented with rice hull showed an inhibitory effect after 30th days, while compost supplemented with rice hull and extruding hull(T2) had an inhibitory effect during all period against Rhizoctonia solani. But treatment with extruding hull(T3) added compost did not have any inhibitory effect against Rhizoctonia solani. Only 63th samples in T1 and T2 treatment showed inhibitory effect against Colletoerichum gloeosporioides. However, T3 did not. Suppressive effect of extracts from 67 kinds of composts was investigated in vitro against plant pathogens, such as Fusauum oxysporum. Alternaria alternata, Colletotrichum gloeospoioides, Rhizoctonia solani, and Botrytis cinerea. Thirty two of them showed inhibitory effect against more than one phytopathogen, nine against one pathogen, four against two, six against three, six against four, and seven against five.

• Korean journal of applied entomology
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• v.32 no.1
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• pp.105-114
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• 1993

Series of studies were conducted to establish biological and chemical control method for Meloidogyne spp to medical herbs by applied of nematophagous fungi, Arthrobotrys spp, Fusarium spp, and egg parastic fungi, Paecilomyces lilacinus were applied for root-knot nematodes on medicinal herbs, Paeonia albiflora, Codonopsis lanceolata, Cnidium officinale. The results are as follow. In pot experiments, The no. of root gall and egg mass and larvae of Cnidium officinale. The results are as follow. In pot experiments. The no. of root gall and egg mass and larvae of Cnidium officinale, Codonopsis lanceolata, Paeonia japonica lowered in P. Lilacinus treated plots compare to untreated control plots. But A. thaumasia F. oxysporum treated plots were less effective. Effect of egg parasitic fungi and chemical treatment at divided root of Paeonia japonica after sterilized in pot were increased in the fresh weight, root weight, control effect in P. lilacinus treated plots as chemical, Carbo G treated plots compare to untreted control plots. I field experiment, the number of root gall, egg mass and nematode density of Paeonia were also suppressed in P. lilacinus treated plots. It was very effective continuous 2 years and transplanting time on Paeonia japonica infested soil with the M. hapla in field in both region, Chillgok and Euisung treated P. lilacinus as chemical treated plots. Soaking effect of insecticide for Paeonia japonica at diving shoot before transplating in pot were effective for 12hours immersion into 1,000 ppm of Benlate T + Mep Ec, Benlate T + Fenthion EC in pot and field Experiment. In the Examination of fungi activily on P.japonica field 1 year after soil treatment, Number of spore of P. lilacinus were 1,000~1,300 in 3 region except Euisung.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.553-563
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• 2019

Investigations related with factors influencing root and crown rot are rare and mainly related to farming practice and soil management. The main objective of this study was to examine broader range of factors influencing stem-base infestation of winter wheat in the field conditions. The effect of spatial distribution of infected plants on disease index (DIs) assessments was also investigated. Analysis of factors influencing DIs of crown rot of wheat demonstrated significant influence of the growing seasons (P < 0.001) and extreme fluctuations in winter temperatures (P < 0.001). In addition to that, localities together with their interaction with the growing season also significantly influenced DIs (P < 0.001). Aggregation of infected plants influenced variability of DI estimations, and it was pointed out that more extensive investigation should be conducted on broad range of DI in order to establish sampling method giving uniform sampling precision. Fusarium graminearum was shown to be predominant Fusarium species in Serbia (72.6%) using sequence-characterized amplified region analysis. Interestingly F. oxysporum was isolated in higher frequencies (27.4%) than it was reported in the literature. Given that there were no reports on the diversity of Fusarium species causing crown rot of wheat in Serbia, this study presents first report on this important subject. It also indicated that more attention should be focused on combined effects of abiotic and biotic factors influencing stem-base infestation of winter wheat. This knowledge will contribute to better understanding of factors influencing root and crown rot of wheat which would ensure sustainable disease management in the future.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.191-202
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• 1998

About 300 actinomycetes were isolated from two forest and one sea-shore soil and tested for inhibitory effects on mycelial growth of six plant pathogenic fungi Magnaporthe grisea, Alternaria mali, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f. sp. cucumerinum, and Rhizoctonia solani. Among 300 actinomycetes tested, only 16 actinomycetes showed the antifungal activity against the test fungi. Isolate NH 50 was selected for production and purification of antifungal antibiotic substances. Actinomycete isolate NH 50 displayed the broad antifungal spectra against 11 plant pathogenic fungi. To identify actinomycete isolate NH 50, cultural characteristics on various agar media, diaminopimelic acid type, and morphological characteristics by scanning electron microscopy were examined. As a result, actinomycete isolate NH 50 was classified as a rare actinomycete that had LL-DAP type and did not produce spores. After incubation of isolate NH 50 in yeast extract-malt extract-dextrose broth, antifungal compound NH-B1 that inhibited mycelial growth of some plant pathogenic fungi was purified from the methanol eluates of XAD-16 resins by a series of purification procedures, i.e., silica gel flash chromatography, C18 flash chromatography, Sephadex LH-20 column chromatography, silica gel medium pressure liquid chromatography (MPLC), C18 MPLC, and high pressure liquid chromatography (HPLC). UV spectrum and 1HNMR spectrum of antifungal compound NH-B1 dissolved in methanol were examined. The antibiotic NH-B1 showed the major peaks at 230 and 271.2nm. Based on the data of 1H-NMR spectrum, NH-B1 was confirmed to be an extremely complex polymer of sugars called polysaccharides. The antibiotic NH-B1 showed strong antifungal activity against Alternaria solani and Cercospora kikuchi, but weak activity against M. grisea.

• Plant Biotechnology Reports
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• v.5 no.3
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• pp.245-254
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• 2011

This study describes an efficient protocol for Agrobacterium tumefaciens-mediated transformation of two subgroups of genotype AAA bananas (Musa acuminata cv. Pei Chiao and Musa acuminata cv. Gros Michel). Instead of using suspension cells, cauliflower-like bud clumps, also known as multiple bud clumps (MBC), were induced from sucker buds on MS medium containing $N^6$-Benzylaminopurine (BA), Thidiazuron (TDZ), and Paclobutrazol (PP333). Bud slices were co-cultivated with A. tumefaciens C58C1 or EHA105 that carry a plasmid containing Arabidopsis root-type ferredoxin gene (Atfd3) and a plant ferredoxin-like protein (pflp) gene, respectively. These two strains showed differences in transformation efficiency. The EHA105 strain was more sensitive in Pei Chiao, 51.3% bud slices were pflp-transformed, and 12.6% slices were Atfd3-transformed. Gros Michel was susceptible to C58C1 and the transformation efficiency is 4.4% for pflp and 13.1% for Atfd3. Additionally, gene integration of the putative pflp was confirmed by Southern blot. Resulting from the pathogen inoculation assay, we found that the pflp transgenic banana exhibited resistance to Fusarium oxysporum f. sp. cubense tropical race 4. This protocol is highly advantageous to banana cultivars that have difficulties in setting up suspension cultures for the purpose of quality improvement through genetic transformation. In addition, this protocol would save at least 6 months in obtaining explants for transformation and reduce labor for weekly subculture in embryogenic cell suspension culture systems.

• The Plant Pathology Journal
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• v.31 no.1
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• pp.50-60
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• 2015

The use of novel isolates of Trichoderma with efficient antagonistic capacity against Fusarium oxysporum f. sp. lycopersici (FOL) is a promising alternative strategy to pesticides for tomato wilt management. We evaluated the antagonistic activity of 30 isolates of T. asperellum against 4 different isolates of FOL. The production of extracellular cell wall degrading enzymes of the antagonistic isolates was also measured. The random amplified polymorphic DNA (RAPD) method was applied to assess the genetic variability among the T. asperellum isolates. All of the T. asperellum isolates significantly reduced the mycelial growth of FOL isolates but the amount of growth reduction varied significantly as well. There was a correlation between the antagonistic capacity of T. asperellum isolates towards FOL and their lytic enzyme production. Isolates showing high levels of chitinase and ${\beta}$-1,3-glucanase activities strongly inhibited the growth of FOL isolates. RAPD analysis showed a high level of genetic variation among T. asperellum isolates. The UPGMA dendrogram revealed that T. asperellum isolates could not be grouped by their antagonistic behavior or lytic enzymes production. Six isolates of T. asperellum were highly antagonistic towards FOL and potentially could be used in commercial agriculture to control tomato wilt. Our results are consistent with the conclusion that understanding the genetic variation within Trichoderma isolates and their biochemical capabilities are required for the selection of effective indigenous fungal strains for the use as biocontrol agents.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.983-989
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• 2007

Bacillus lichemiformis Kll, a plant growth promoting rhizobacterium was reported as a producer of auxin, siderophore, as well as antifungal cellulase under some culture conditions. In vitro test, B. licheniformis Kll represented excellent antagonistic ability against Fusarium oxyspoum (KACC 40037), and showed broad spectrum against other phytopathogenic fungi. B. licheniformis Kll had cellulolytic activity toward not only carboxymethyl-cellulose (CMC) but also insoluble cellulose, such as fungal cell wall cellulose, filter paper (Whatman No. 1), and Avicel. In addition, we confirmed antifungal substance production by butanol-extract methods. The strain produced optimally the antifungal substance when it was cultivated at pH 9.0, 30${\circ}$C for 4 days on nutrient medium. The biological control mechanisms of B. lichemiformis Kll were caused by antifungal substance, cellulase and siderophore against phytopathogenic fungi.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.485-491
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• 2015

This study was performed to investigate thermophilic bacteria from soil having broad antifungal spectrum against Rhizoctonia solani, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f.sp. lycopersici, and Botrytis cinerea. One isolate selected could resist heat shock of $60^{\circ}C$ for one hour, and had broad antifungal activity in dual culture assay against all tested fungal pathogens and was identified as Bacillus amyloliquefaciens Y1 using 16S rRNA gene sequence. Further investigation for antifungal activity of bacterial culture filtrate (BCF) and butanol crude extract (BCE) of various concentrations showed broad spectrum antifungal activity and fungal growth inhibition significantly increased with increasing concentration with highest growth inhibition of 100% against R. solani with 50% BCF and 11 mm of zone of inhibition against R. solani with 4 mg BCE concentration. Treatment of butanol crude extract resulted in deformation, lysis or degradation of C. gloeosporioides and P. capsici hyphae. Furthermore, B. amyloliquefaciens Y1 produced volatile compounds inhibiting growth of R. solani (70%), C. gloeosporioides (65%) and P. capsici (65-70%) when tested in volatile assay. The results from the study suggest that B. amyloliquefaciens Y1 could be a biocontrol candidate to control fungal diseases in crops.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.305-315
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• 2021

The cotton leafworm, Spodoptera littoralis, is a major pest in Egypt and many countries worldwide, and causes heavy economic losses. As a result, management measures to control the spread of the worm are required. S. littoralis nucleopolyhedrovirus (SpliNPV) is one of the most promising bioagents for the efficient control of insect pests. In this study, a chitinase gene (chitA) of a 1.8 kb DNA fragment was cloned and fully characterized from SpliNPV-EG1, an Egyptian isolate. A sequence of 601 amino acids was deduced when the gene was completely sequenced with a predicted molecular mass of 67 kDa for the preprotein. Transcriptional analyses using reverse transcription polymerase chain reaction (RT-PCR) revealed that chitA transcripts were detected first at 12 h post infection (hpi) and remained detectable until 168 hpi, suggesting their transcriptional regulation from a putative late promoter motif. In addition, quantitative analysis using quantitative RT-PCR showed a steady increase of 7.86-fold at 12 hpi in chitA transcription levels, which increased up to 71.4-fold at 120 hpi. An approximately 50 kDa protein fragment with chitinolytic activity was purified from ChitA-induced bacterial culture and detected by western blotting with an anti-recombinant SpliNPV chitinase antibody. Moreover, purification of the expressed ChitA recombinant protein showed in vitro growth inhibition of two different fungi species, Fusarium solani and F. oxysporum, confirming that the enzyme assembly and activity was correct. The results supported the potential role and application of the SpliNPV-ChitA protein as a synergistic agent in agricultural fungal and pest control programs.

• Journal of Microbiology and Biotechnology
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• v.29 no.1
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• pp.66-78
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• 2019

In this study, strain KNU17Pc1 was tested for its antifungal activity against Rhizoctonia solani AG-1(IA), which causes banded leaf and sheath blight (BLSB) of maize. KNU17Pc1 was tested further for its broad-spectrum antifungal activity and in vitro plant growth promoting (PGP) traits. In addition, the in vivo effects of KNU17Pc1 on reduction of BLSB severity and seedling growth promotion of two maize cultivars under greenhouse conditions were investigated. On the basis of multilocus sequence analysis (MLSA), KNU17Pc1 was confirmed as P. chlororaphis subsp. aurantiaca. The study revealed that KNU17Pc1 had strong in vitro antifungal activity and was effective toward all in vitro PGP traits except phosphate solubilization. In this study, for the first time, a strain of P. chlororaphis against Colletotrichum dematium, Colletotrichum gloeosporioides, Fusarium oxysporum f.sp. melonis, Fusarium subglutinans and Stemphylium lycopersici has been reported. Further biochemical studies showed that KNU17Pc1 was able to produce both types of phenazine derivatives, PCA and 2-OH-PCA. In addition, solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis identified 13 volatile organic compounds (VOCs) in the TSB culture of KNU17Pc1, 1-undecene being the most abundant volatile. Moreover, for the first time, Octamethylcyclotetrasiloxan (D4), dimethyl disulfide, 2-methyl-1,3-butadiene and 1-undecene were detected in P. chlororaphis. Furthermore, this study reported for the first time the effectiveness of P. chlororaphis to control BLSB of maize. Hence, further studies are necessary to test the effectiveness of KNU17Pc1 under different environmental conditions so that it can be exploited further for biocontrol and plant growth promotion.