Antagonistic activity and molecular characterization of biological control agent Trichoderma harzianum from Saudi Arabia

A total of 91 isolates of probable antagonistic bacteria of potato soft rot bacteriumErwinia carotovorasubsp.carotovora(Ecc) were extracted from rhizospheres and endophytes of various crop plants, different soil varieties, and atmospheres in the potato farming areas of Bangladesh. Antibacterial activity of the isolated probable antagonistic bacteria was testedin vitroagainst the previously identified most common and most virulent soft rot causing bacterial strain Ecc P-138. Only two isolates E-45 and E-65 significantly inhibited thein vitrogrowth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genusBacillusand the isolate E-45 asLactobacillussp. The stronger antagonistic activity against Ecc P-138 was found in E-65in vitroscreening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5%) antagonistic effect of E-65 was observed in the Granola and the lowest (32.7%) of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers.

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Characterization of a Genomic Region Required for Production of the Antibiotic Pyoluteorin by the Biological Control Agent Pseudomonas fluorescens Pf-5.

Applied and Environmental Microbiology ◽

10.1128/aem.61.3.849-854.1995 ◽

1995 ◽

Vol 61 (3) ◽

pp. 849-854 ◽

Cited By ~ 112

Author(s):

J Kraus ◽

J E Loper

Keyword(s):

Biological Control ◽

Pseudomonas Fluorescens ◽

Biological Control Agent ◽

Control Agent ◽

Genomic Region

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Identification of the Fungal Pathogens of Postharvest Disease on Peach Fruits and the Control Mechanisms of Bacillus subtilis JK-14

Toxins ◽

10.3390/toxins11060322 ◽

2019 ◽

Vol 11 (6) ◽

pp. 322 ◽

Cited By ~ 11

Author(s):

Shuwu Zhang ◽

Qi Zheng ◽

Bingliang Xu ◽

Jia Liu

Keyword(s):

Biological Control ◽

Bacillus Subtilis ◽

Fungal Pathogens ◽

Biological Control Agent ◽

Storage Period ◽

Control Agent ◽

Antagonistic Activity ◽

Postharvest Disease ◽

Economic Losses ◽

Control Mechanisms

Postharvest fungal disease is one of the significant factors that limits the storage period and marketing life of peaches, and even result in serious economic losses worldwide. Biological control using microbial antagonists has been explored as an alternative approach for the management of postharvest disease of fruits. However, there is little information available regarding to the identification the fungal pathogen species that cause the postharvest peach diseases and the potential and mechanisms of using the Bacillus subtilis JK-14 to control postharvest peach diseases. In the present study, a total of six fungal isolates were isolated from peach fruits, and the isolates of Alternaria tenuis and Botrytis cinerea exhibited the highest pathogenicity and virulence on the host of mature peaches. In the culture plates, the strain of B. subtilis JK-14 showed the significant antagonistic activity against the growth of A. tenuis and B. cinerea with the inhibitory rates of 81.32% and 83.45% at 5 days after incubation, respectively. Peach fruits treated with different formulations of B. subtilis JK-14 significantly reduced the mean disease incidences and lesion diameters of A. tenuis and B. cinerea. The greatest mean percent reduction of the disease incidences (81.99% and 71.34%) and lesion diameters (82.80% and 73.57%) of A. tenuis and B. cinerea were obtained at the concentration of 1 × 107 CFU mL−1 (colony forming unit, CFU). Treatment with the strain of B. subtilis JK-14 effectively enhanced the activity of the antioxidant enzymes-superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in A. tenuis and B. cinerea inoculated peach fruits. As such, the average activities of SOD, POD and CAT were increased by 36.56%, 17.63% and 20.35%, respectively, compared to the sterile water treatment. Our results indicate that the isolates of A. tenuis and B. cinerea are the main pathogens that cause the postharvest peach diseases, and the strain of B. subtilis JK-14 can be considered as an environmentally-safe biological control agent for the management of postharvest fruits diseases. We propose the possible mechanisms of the strain of B. subtilis JK-14 in controlling of postharvest peach diseases.

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EKSPLORASI DAN IDENTIFIKASI TRICHODERMA ENDOFITIK PADA PISANG

JURNAL HAMA DAN PENYAKIT TUMBUHAN TROPIKA ◽

10.23960/j.hptt.216115-123 ◽

2017 ◽

Vol 16 (2) ◽

pp. 115

Author(s):

Johanna Taribuka ◽

Christanti Sumardiyono ◽

Siti Muslimah Widyastuti ◽

Arif Wibowo

Keyword(s):

Biological Control ◽

Phylogenetic Analysis ◽

Endophytic Fungi ◽

Trichoderma Harzianum ◽

Biocontrol Agent ◽

Biological Control Agent ◽

Control Agent ◽

Selective Medium ◽

Trichoderma Spp ◽

Its1 And Its2

Exploration and identification of endophytic Trichoderma in banana. Endophytic fungi Trichoderma is an organism that can used as biocontrol agent. This study aims to isolate and identify endophytic Trichoderma in roots of healthy banana plants from three districts in Yogyakarta, which will be used as biological control agent against the pathogen Fusarium oxysporum f.sp. cubense. Isolation was conducted using TSM (Trichoderma Selective Medium). We obtained six isolates of endophytic Trichoderma spp., i.e., Swn-1, Swn-2, Ksn, Psr-1, Psr-2, and Psr-3. Molecular identification was done by using ITS1 and ITS2 primer pain and sequenced. The sequence of DNA obtained was analysed and compared with NCBI database by using BLAST-N programe. The results showed that all isolates were amplified at 560-bp. Phylogenetic analysis showed that isolates Swn-1, Swn-2 and Psr-1 are homologous to Trichoderma harzianum, isolate Ksn homologous to Trichoderma asperrellum, isolate Psr-2 homologous to Trichoderma gamsii, and isolate Psr-3 homologous to Trichoderma koningiopsis, with the homologous value of 99%.

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Pellet Formulation of Trichoderma Isolated from Aceh with Potential for Biocontrol of Phytophthora Sp. on Cacao Sedlings

Journal of Applied Agricultural Science and Technology ◽

10.32530/jaast.v3i2.120 ◽

2019 ◽

Vol 3 (2) ◽

pp. 202-212

Author(s):

Rina Sriwati ◽

Tjut Chamzhurni ◽

Alfizar Alfizar ◽

Bonny PW Soekarno ◽

Vina Maulidia ◽

...

Keyword(s):

Biological Control ◽

Disease Severity ◽

Trichoderma Harzianum ◽

Biological Control Agent ◽

Control Agent ◽

Diameter Growth ◽

Good Ability ◽

Trichoderma Isolate ◽

Pellet Formulation

Molleculler study was conducted to identify several species of Trichoderma isolate from several plant (Pine, Cacao, Gliceria, Nutmeg, Bamboo, Coffee, Potato). The growth of eight species Trichodermaafter pelleting formulation has been observed. Pellet Trichoderma harzianum have good ability to growth on PDA medium after 4 weeks storage. Base on their mycelium diameter growth on PDA, T. harzianum have selected as potential species on pellet formulation growth. Several dose of pellet formulation have been applied for controlling Phythopthora disease. The application of T. harzianum pellets in the form of a 2 g / 100 ml (S1) suspension effective in inhibiting the development of Phytophthora sp in cacao seedlings, when the higher concentrations of T. harzianum pellets applied to cacao seeds,the disease severity increase. Pellet Trichoderma could be use as biological control agent of cacao seedling in certain dosage.

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