• Mycobiology
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• v.47 no.2
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• pp.230-241
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• 2019

The Great Sebkha of Oran is a closed depression located in northwestern of Algeria. Despite the ranking of this sebkha among the wetlands of global importance by Ramsar Convention in 2002, no studies on the fungal community in this area have been carried out. In our study, samples were collected from two different regions. The first region is characterized by halophilic vegetation and cereal crops and the second by a total absence of vegetation. The isolated strains were identified morphologically then by molecular analysis. The biotechnological interest of the strains was evaluated by testing their ability to grow at different concentration of NaCl and to produce extracellular enzymes (i.e., lipase, amylase, protease, and cellulase) on solid medium. The results showed that the soil of sebkha is alkaline, with the exception of the soil of cereal crops that is neutral, and extremely saline. In this work, the species Gymnoascus halophilus, Trichoderma gamsii, the two phytopathogenic fungi, Fusarium brachygibbosum and Penicillium allii, and the teleomorphic form of P. longicatenatum observed for the first time in this species, were isolated for the first time in Algeria. The halotolerance test revealed that the majority of the isolated are halotolerant. Wallemia sp. and two strains of G. halophilus are the only obligate halophilic strains. All strains are capable to secrete at least one of the four tested enzymes. The most interesting species presenting the highest enzymatic index were Aspergillus sp. strain A4, Chaetomium sp. strain H1, P. vinaceum, G. halophilus, Wallemia sp. and Ustilago cynodontis.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.548-552
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• 1991

The effect of dual inoculation with vesicular-arbuscular (VA) mycorrhizal fungi, Glomus mosseae, and Bradyrhizobium sp. R938 on the nitrogenase activity of peanut plant (Arachis hypogeae L. cv. Youngho) was studied in pot experiment. As a result of the dual inoculation with Glomus mosseae and Bradyrhizobium on peanut plant, nitrogenase activity was increased by 1.5 times compared with single inoculation with Bradyrhizobium sp. R938. After 69 days growth of peanut plant, the size of nodules was also increased due to the mycorrhizal infection. The mean fresh weight per nodule was 6.7 mg in treatment with the dual inoculation, which is the 1.5 times increase compared with single inoculation with Bradyrhizobium sp. R938. These results suggested that there might be a hormonal effect of VA mycorrhizal fungi in addition to the effect of increase in nitrogen fixing ability through the enhancement of nutrient absorption.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.291-300
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• 1998

A study was carried out to evaluate the effect of different salts and their Quantities on the fluctuation and rhizosphere colonization of soil microorganisms. The results obtained are as follows. The electrical conductivities(ECs) of $KNO_3$, $K_2HPO_4$, KCl and $K_2SO_4$ showed negative correlations to the number of gram positive bacteria and gram negative bacteria : the number of bacteria was significantly decreased in the KCl or $KNO_3$ treated group compared to the $K_2HPO_4$ or $K_2SO_4$ treated group. The highest microorganism density of gram negative bacteria, gram positive bacteria and Fusarium sp. in balanced salts-treated soil was observed at $0.5dS\;m^{-1}$, $2.1dS\;m^{-1}$ and $8.0dS\;m^{-1}$ of EC, respectively. The ratio of bacteria to fungi ratio in balanced salts-treated soil substantially decreased as the EC of soil increased. Ten and thirty days after soil treatment with balanced salts, the ratio of bacteria to fungi decreased to 757-1571 and 89-215, respectively. Root colonization density of Fluorescent Pseudomonas in cucumber and tomato significantly decreased as the EC of soil increased, whereas that of Fusarium sp. increased.

• Mycobiology
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• v.49 no.1
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• pp.69-77
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• 2021

The application of antagonistic fungi for plant protection has attracted considerable interest because they may potentially replace the use of chemical pesticides. Antipathogenic activities confirmed in volatile organic compounds (VOCs) from microorganisms have potential to serve as biocontrol agents against pre- and post-harvest diseases. In the present study, we investigated Galactomyces fungi isolated from rotten leaves and the rhizosphere of cherry tomato (Lycopersicon esculentum var. cerasiforme). VOCs produced by Galactomyces fungi negatively affected the growth of phytopathogenic fungi and the survival of nematodes. Mycelial growths of all nine examined phytopathogenic fungi were inhibited on agar plate, although the inhibition was more intense in Athelia rolfsii JYC2163 and Cladosporium cladosporioides JYC2144 and relatively moderate in Fusarium sp. JYC2145. VOCs also efficiently suppressed the spore germination and mycelial growth of A. rolfsii JYC2163 on tomatoes. The soil nematode Caenorhabditis elegans exhibited higher mortality in 24 h in the presence of VOCs. These results suggest the broad-spectrum activity of Galactomyces fungi against various plant pathogens and the potential to use VOCs from Galactomyces as biocontrol agents.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.108-110
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• 2009

The composition of endophytic fungal species from Pinus koraiensis was studied in two areas (Yeongwol and Jincheon), Korea. To identify 113 isolates, rDNA ITS regions were sequenced. On the basis of the ITS sequence, Pestalotiopsis sp. was the most frequently isolated species in both areas. Pestalotiopsis sp. (68.5%) and Lambertella sp. (12.4%) were isolated frequently in Yeongwol, whereas Pestalotiopsis sp. (41.7%), Hypoxylon sp. (20.8%) and Phomopsis sp. (12.4%) were dominant in Jincheon. Hypoxylon sp. and Phomopsis sp. were not found in Yeongwol.

• Plant Disease and Agriculture
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• v.1 no.1
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• pp.19-29
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• 1995

A microbial product composed of three antagonistic fungal isolates (Aspergillus sp., Penicillium sp. and Trichoderma sp.) and three bacterial isolates (Arthrobacter sp., Bacillus sp., and Pseudomonas sp.) was tested for the control of Pythium blight caused by Pythium sp., brown patch by Rhizoctonia solani (anastomosis group(AG) 1-1) and large patch by R. solani (AG 2-2) of turfgrasses. Cultures of the antagonistic fungi and bacteria varied in the effectiveness in reducing disease severity of Pytium blight and brown patch on bentgrass. The antagonistic fungal and bacterial isolates were mixed and cultured at 20-$25^{\circ}C$ for 3 days in a growth medium, and the diluted solution of the microbial culture was applied under the field conditions after inoculation of the above turfgrass pathogens. The treated turfgrass was incubated at 28$^{\circ}C$ in a growth chamber. In this experiment, Pythium blight was almost completely controlled and brown patch was slightly decreased by the microbial product, while no control was observed in large patch of zoysiagrass. In zoysiagrass treated with the microbial culture, thatch accumulation was notably reduced.

• Journal of Sericultural and Entomological Science
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• v.44 no.1
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• pp.32-36
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• 2002

Occurrence and characteristics of infectious fungi and physiologically abnormal Paecilomyces tenuipes were examined. These unfavorable fungi are recently known to cause yield loss, decreased quality of products in artificial cultivation farms of P. tenuipes. Total 529 fungal isolates were collected from 22 farms of 7 provinces. These isolates were composed of physiologically abnormal P. tenuipes strains and other infectious fungal strains, which constituted 23.2% and 50.9%, respectively. Physiologically abnormal P. tenuipes strains showed irregular synemata, and absence of local color. They were divided into 4 types or C-l, C-2, C-3 and C-4. Other infectious fungal strains were identified to 5 species, Beauveria bassiana, Fusarium sp., P fumosoroseus, Tricothecium roseum, Aspergillus parasiticus, which were 22.1, 13.8, 7.6, 4.0 and 3.4%, respectively. All of them were hyphomycetous fungi, did not produce synemata, and revealed faster growth rate than that of P. tenuipes.

• Journal of Mushroom
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• v.17 no.4
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• pp.179-184
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• 2019

This study was conducted to investigate the diversity of culture-dependent fungal species in the sawdust media of Lentinula edodes. A total of 405 fungi were isolated from the specimens and identified to belong to 24 genera and 42 species. Among the identified 42 species of fungi, 26.2% belonged to Penicillium sp., 9.5% belonged to Trichoderma sp., and 64.3% belonged to others. Especially, Trichoderma harzianum, which is a causal agent of fungal disease in mushroom, was found on all the farms, and showed the highest frequency among the identified fungi. Community analysis showed that the fungal diversity patterns of the samples were similar to each farm and many kinds of fungi existed in the sawdust media at high levels. These results showed that the management of internal environments would be required for the stable cultivation of Lentinula edodes.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.459-471
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• 2019

Several species of Aquilaria and Gyrinops are native to Indonesia and well known as agarwood-producing trees with a high economic value. Their bioactive compounds have a wide spectrum of uses, such as in medicine and cosmetics. These genera have undergone extensive search for novel bioactive compounds. The purpose of this study was to isolate, identify, and characterize the endophytic fungi community associated with Aquilaria malaccensis, A. microcarpa, Gyrinops versteegii, and A. crassna trees and investigate their bioactive properties as antioxidant agents and antagonists. A total of 50 fungi were successfully isolated from different tissues of the four species of agarwood-producing trees. Two isolates exhibited strong antioxidant activity, namely, Apodus oryzae (R2MC3A, $IC_{50}$ 60.92 mg/mL) and Diaporthe sp. (P1DS1[C], $IC_{50}$ 76.65 mg/mL). Two isolates, Pestalotiopsis theae (P3BS3[B]) and Curvularia sp. (P2CD3A), showed >75% antifungal activity against pathogenic Fusarium solani. The results revealed that endophytic fungi associated with the studied agarwood-producing trees had potential antioxidant and antifungal activities for further applications in biotechnology.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.212-217
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• 1999

The effects of nuruk and wheat bran on cholesterol level in serum and activities of free radical metabolizing enzymes were investigated in rats. The rats were fed a diet containing nuruk or wheat bran for one month. Body weight and food intake were measured. Animals were sacrificed after one month. The increased food efficiency ratio throughout whole growth period was observed in the rats fed with either nuruk containing Aspergillus terreus or wheat bran compared with control group on normal diet. In the rats fed with nuruk, hepatic GSH content, glutathione S transferase activity, hepatic cytochrome P 450 content, and aniline hydroxylase activities were generally increased. In the rats fed with nuruk containing other fungi except Aspergillus terreus, xanthine oxidase activity was decreased. The decreased cholesterol level in serum was observed in rats fed with nuruk prepared from Aspergillus terreus and wheat bran. LDL cholesterol level was decreased in rats fed with nuruk prepared with other fungi such as Penicillium sp. and Rhizopus sp. But HDL cholesterol level was increased in all groups fed with nuruk from any fungi and wheat bran. These results suggested that nuruk or wheat bran supplemented diet might exert their effect by decreasing cholesterol level in serum and amount of oxygen free radical level.