• 한국균학회지
• /
• 제38권2호
• /
• pp.120-124
• /
• 2010

본 시험은 재배과정 중 균상배지에서 분리한 세균들의 특성을 조사하여 버섯균의 생육 및 병원균과의 연관관계를 밝히고자 하였다. 정상적으로 버섯을 수확한 농가의 경우 버섯생육초기에 분리한 세균일수록 버섯균주에 대해 저해정도가 감소하였으나, 생육이 진행될수록 저해균의 수가 증가하였으나, 버섯 수확에 실패한 농가의 경우 반대의 경향을 보였다. 또한 합성배지에 분리세균을 도말한 후 느타리버섯 균의 생육을 조사한 결과 정상적 농가의 경우 살균 직후 보다 생육이 진행될수록 저해균의 수가 증가하였지만, 실패한 농가는 오히려 반대의 경향을 보였다. 그러나 톱밥배지에서는 버섯생육초기보다 후기에 분리한 세균이 저해하는 정도가 오히려 낮았다. 또한 이들 분리 세균은 분비성 물질을 통해서 버섯균의 생육과 증식에 영향을 미쳤다. 분리 미생물 중 세균성갈반병의 원인균인 Pseudomonas tolaasii을 강하게 억제하는 미생물은 거의 없었으며 소수의 균주에서 약한 길항력을 보였다. 그러나 세균성갈색무늬병을 일으키는 P. agarici에 대해서는 강한 억제력을 보이는 균주가 많이 존재하였으며, 푸른곰팡이병의 원인균인 Trichoderma harzianum을 강하게 억제하는 미생물도 배지내에 거의 존재하지 않았다. 이와 같이 배지내에는 다양한 미생물이 존재하고 이들 다양한 미생물과 버섯균의 상호작용에 대한 면밀한 연구가 이루어진다면 느타리버섯 재배과정 중 발생하는 다양한 문제점을 해결할 수 있는 좋은 방법이 될 수 있을것으로 생각된다.

• Journal of Microbiology and Biotechnology
• /
• 제28권5호
• /
• pp.831-838
• /
• 2018

Trophic interactions of introduced biocontrol fungi with soil animals can be a key determinant in the fungal proliferation and activity. This study investigated the trophic interaction of an introduced biocontrol fungus with soil nematodes. The biocontrol fungus Trichoderma harzianum ThzID1-M3 and the fungivorous nematode Aphelenchoides sp. (10 per gram of soil) were added to nonsterile soil, and microbial populations were monitored for 40 days. Similar results were obtained when the experiment was duplicated. ThzID1-M3 stimulated the population growth of indigenous nematodes (p < 0.05), regardless of whether Aphelenchoides sp. was added. Without ThzID1-M3, indigenous nematodes did not increase in number and the added Aphelenchoides sp. nematodes almost disappeared by day 10. With ThzID1-M3, population growth of nematodes was rapid between 5 and 10 days after treatment. ThzID1-M3 biomass peaked on day 5, dropped at day 10, and then almost disappeared at day 20, which was not influenced by the addition of nematodes. In contrast, a large quantity of ThzID1-M3 hyphae were present in a heat-treated soil in which nematodes were eliminated. Total fungal biomass in all treatments peaked on day 5 and subsequently decreased. Addition of nematodes increased the total fungal biomass (p < 0.05), but ThzID1-M3 addition did not affect the fungal biomass. Hyphae of total fungi when homogenously distributed did not support the nematode population growth; however, hyphae of the introduced fungus did when densely localized. The results suggest that soil fungivorous nematodes are an important constraint on the hyphal proliferation of fungal agents introduced into natural soils.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제20권1호
• /
• pp.1-5
• /
• 2010

The studies have been conducted to control the soil borne fungal pathogens viz, Fusarium solani (Mart) Sacc. and Alternaria tenuissima the incitants of root rot and die-back diseases on mulberry stem cuttings planted in the mulberry nurseries and also in established mulberry gardens ten plant extracts with 10% concentration except Lantana camara (undiluted) were tested through poisoned food technique and four biofungicides were also screened by dual culture method under in vitro conditions. Plant extract of Prosopis juliflora showed the maximum inhibition on the mycelial growth (81.2% over A. tenuissima and 80.0% over F. solani) and followed by L. camara (66.7% over A. tenuissima and 68.9% over F. solani). Among the antagonists Pseudomonas fluorescens and Trichoderma viride showed maximum inhibition on the mycelial growth of both pathogenic fungi. The promising plant extracts (P. juliflora and L. camara) and antagonists (P. fluorescens and T. viride) were tested against both the pathogenic fungi under in vivo conditions along with the existing popular chemical Mancozeb. All the tested plant products and bio-fungicides showed inhibitory effect on both fungi. But the maximum survival percentage of mulberry cuttings was recorded in the treatment with T. viride (95% against F. solani and 90% against A. tenuisssima) followed by P. fluorescens (90% against both fungi) and T. harzianum (80% against F. solani and 85% against A. tenuisssima). Incase of the treatments with plant extracts and chemical fungicide the P. juliflora (60% against F. solani and 55% against A. tenuisssima) showed higher survival percentage and followed by L. camara (55% against F. solani and 50% against A. tenuisssima) and Mancozeb (55% against both fungi). In case of control only 10% of survival was recorded in F. solani inoculated cuttings and 15% survival in A. tenuissima inoculated cuttings.

• The Plant Pathology Journal
• /
• 제15권3호
• /
• pp.162-167
• /
• 1999

Integration of microbial antagonists with fungicides was tried to control the gray mold caused by Botrytis cinerea on pepper in greenhouse conditions and to reduce fungicide uses. All of the selected bacterial antagonists, Bacillus amyloliquefaciens BL3, Paenibacillus polymyxa BL4, and Pseudomonas putida Cha94, completely inhibited the conidial germination of B. cinerea until 30 days after treatment. However, bacterial colonization of pepper phylloplane was poor in BL4, while the other bacterial isolates and the fungal antagonist Trichoderma harzianum TM colonized well on the phylloplane, maintaining the population density of 104-105 cfu/g until 15 days after microbial treatments. Out of 13 kinds of selected fungicides used for gray mold diseases, polyoxin B and BKF 1995 showed the most discriminatory activity on the fungal growth between B. cinerea and TM. TM grew readily on the media containing those fungicides, while B. cinerea showed poor or no mycelial growth on them. The selected fungicides and antagonists alone reduced incidence of gray mold on pepper, showing disease indices of about 2.4 to 3.0, while its was increased up to 4.2 in the untreated control. Alternate treatments with the antagonists and 2-fold diluted fungicides inhibited the disease incidence as much as the antagonists or fungicides alone, and reduced the secondary inoculum more than the single treatments. This suggests that integration of antagonists and fungicides may be an efficient way to reduce fungicide sprays with reliable control efficacy of the disease. However, there was not much difference in the early and mid-term disease progress among the treatments and the untreated control, probably due to extremely favorable environmental conditions for the disease development in this experiment.

• The Plant Pathology Journal
• /
• 제34권2호
• /
• pp.121-125
• /
• 2018

Maize (Zea mays L.; 2N=20) is major staple food crop grown worldwide adapted to several biotic and abiotic stresses. Maydis leaf blight (MLB) and banded leaf and sheath blight (BLSB) are serious foliar fungal diseases may cause up to 40% and 100% grain yield loss, respectively. The present studies were undertaken to work out the efficacy of chemicals, botanicals and bioagents for the management of MLB and BLSB under field condition for two seasons Kharif 2014 and 2015. Five molecules (propiconazole 25 EC, hexaconazole 25 EC, carbendazim 50 WP, mancozeb 75 WP and carbedazim 12 WP + mancozeb 63 WP), two bioagents i.e. Trichoderma harzianum and T. viridae and three botanicals namely azadirachtin, sarpagandha and bel pathar were tested for their efficacy against MLB. Eight newer fungicides viz., difenconazole 250 SC, hexaconazole 5 EC, carbendazim 50WP, validamycin 3 L, tebuconazole 250 EC, trifloxystrobin 50 WG + tebuconazole 50 WG, azoxystrobin 250 EC and pencycuron 250 SC were evaluated against BLSB. Analysis revealed significant effects of propiconazole at 0.1%, carbendazim 12 WP + mancozeb 63 WP at 0.125% and sarpagandha leaves at 10% against MLB pathogen, whereas validamycin at 0.1% and trifloxystrobin 25 WG + tebuconazole 50 WG at 0.05% were found effective against BLSB. The slow rate of disease control virtually by the bioagents might have not shown instant effect on plant response to the yield enhancing components. The identified sources of management can be used further in strengthening the plant protection in maize against MLB and BLSB.

• Journal of Microbiology and Biotechnology
• /
• 제22권7호
• /
• pp.883-888
• /
• 2012

The efficacy of cowdung, Bangladesh Institute of Nuclear Agriculture (BINA)-biofertilizer, and Bangladesh Agricultural University (BAU)-biofungicide, alone or in combination, was evaluated for controlling foot rot disease of lentil. The results exhibited that BINA-biofertilizer and BAU-biofungicide (peat soil-based Rhizobium leguminosarum and black gram bran-based Trichoderma harzianum) are compatible and have combined effects in controlling the pathogenic fungi Fusarium oxysporum and Sclerotium rolfsii, which cause the root rot of lentil. Cowdung mixing with soil (at 5 t/ha) during final land preparation and seed coating with BINA-biofertilizer and BAU-biofungicide (at 2.5% of seed weight) before sowing recorded 81.50% field emergence of lentil, which showed up to 19.85% higher field emergence over the control. Post-emergence deaths of plants due to foot rot disease were significantly reduced after combined seed treatment with BINA-biofertilizer and BAU-biofungicide. Among the treatments used, only BAU-biofungicide as the seed treating agent resulted in higher plant stand (84.82%). Use of BINA-biofertilizer and BAU-biofungicide as seed treating biocontrol agents and application of cowdung in the soil as an organic source of nutrient resulted in higher shoot and root lengths, and dry shoot and root weights of lentil. BINA-biofertilizer significantly increased the number of nodules per plant and nodules weight of lentil. Seeds treating with BAU-biofungicide and BINA-biofertilizer and soil amendment with cowdung increased the biomass production of lentil up to 75.56% over the control.

• Applied Biological Chemistry
• /
• 제45권2호
• /
• pp.71-76
• /
• 2002

세균성 갈색무늬병과 푸른곰팡이 병에 길항력을 갖는 느타리버섯배지를 개발하기 위해서 자연계로부터 항균 미생물을 순수분리하였다. 분리균주가 생산하는 섬유성분해 효소 및 전분분해 효소의 활성을 검토한 결과 SD-1, 10, 11 및 16균주는 carboxy methyl cellulase(CMCase) 활성이 높았고, SD-4, 10, 14 및 15균주는 glucoamylase활성이 높은 것으로 나타났다. 그리고 이들 분리 균주는 carboxy methyl cellulose(CMC) 및 전분 함유 평판배지에서 뚜렷한 clear zone을 형성하였다. 병원성균에 대한 항균력을 검토한 결과 SD-10과 SD-11은 Pseudomonas tolaasii ATCC-14340 및 P. tolaasii ATCC-51312의 병원균에 강한 길항작용을 나타내었고, SD-1, SD-10및 SD-ll은 푸른곰팡이 병을 유발하는 Trichoderma virence와 T. harzianum에 강한 길항작용을 나타내었다. 분리균과 버섯 균사체와의 생육관계를 검토한 결과 SD-1은 Pleurotus ostreatus ASI-2042에, SD-15는 Pleurotus ostreatus ASI-2180에 약간의 생육저해를 일으킬 뿐 다른 분리균주들은 전혀 버섯균사체의 생육에 영향을 미치지 못하였다. 분리균주의 최적생육온도는 $30{\sim}35^{\circ}C$이었고, 생육가능온도 범위는 $15^{\circ}C{\sim}55^{\circ}C$로 매우 넓었다. 분리균 중에서 SD-1, 10 및 11균주를 느타리버섯 재배현장에 적용시켰을 때 대조구에 비하여 분리균을 접종한 시험구에서는 느타리버섯의 균사 및 자실체의 성장이 매우 균일하고 버섯의 품질이 우수하였다. 그리고 분리균 중에서 SD-10과 11을 균체지방산 조성을 검토한 결과 Bacillus sp.과 아주 유사하였다. 수자원의 절약과 하천수량의 증대에도 기여할 수 있을 것이다. (2.21%), 그리고 열매에서는 ${\alpha}-pinene$ (20.24%) > 1,8-cineole (11.47%) > ${\beta}-pinene$ (9.79%) > u-terpineol (7.08%) > sabinene (3.68%) limonene (2.77%)의 순서로 조성비율이 높았다. 전반적으로 순비기나무의 잎과 열매에서 분리한 정유에서는 monoterpene류의 조성비율이 높았으나 꽃과 줄기에서는 잎이나 열매에 비해 sesquitepene류, diterpene류 이외에도 구조를 동정하지 못하였으나 diterpene류 일 것으로 예상되는 분자량이 비교적 큰 성분들의 조성비율이 높았다./TEX>에서는 TA98 균주에서 $(100{\mu}g/plate)$의 시료농도에서는 부탄올 분획물이 89.92%로 가장 높은 억제효과를 보였으며 TA100 균주에서는 메탄올 추출물이 77.47%로 가장 높은 억제효과를 나타내었다. 암세포주(A549, Hep3B, MCF-7)에 대한 씀바귀 뿌리추출물의 세포독성을 알아보기 위하여 실험한 결과, 페암세포주인 A549세포에서는 에칠아세테이트 분획물$(250{\mu}g/ml)$이 91.67%로 가장 높은 억제효과를 나타내었고, 간암세포주인 Hep3B에서는 에칠아세테이트 분획물 $(500{\mu}g/ml)$이 75.01%로 가장 높은 억제효과를 나타냈으며, 유방암 세포주인 MCF-7에서도 에칠아세테이트 분획물$(500{\mu}g/ml)$이 84%로 가장 높은 억제효과를 보였다. 정상 간세포주인 293에 대하여 시료농도에 따른 세포독성 효과를 나타낸 것으로 $(500{\mu}g/ml)$ 시료 첨가시 암세포에 대하여 대부분 50% 전후(물 분획물 제외)의