The present study was conducted to biocontrol in vitro and in vivo of Fusarium
oxysporum that cause Fusarium wilt diseases for eggplant plants by using biological
control agent fungus Trichoderma harzianum. Fourteen isolates from F. oxysporum
were isolated and identified from two fields in Iraq. Pathogenicity test indicated that
all F. oxysporum isolates were pathogenic for eggplant but differed in its level of
pathogenicity. Four of the fourteen isolates from F. oxysporum were selected
depending on their highest pathogenicity for eggplant plants, F. oxysporum four
isolates F5, F6, F13 and F14 achieved at pre emergence 83.3%, 83.3%, 86.7% and
83.3% and at post emergence 90.0%, 90.0%, 83.3% and 76.7% respectively. In
vitro, the antagonistic activity evaluation of T. harzianum against F. oxysporum four
isolates revealed that T. harzianum was highly significantly inhibited F. oxysporum
four isolates growth (F5, F6, F13, F14) which recorded the inhibition percentage
87.00, 89.00, 89.00, and 96.33% respectively. Greenhouse (In vivo) results of the
biocontrol efficiency of T. harzianum against F. oxysporum showed significant
reduction in eggplant Fusarium wilt incidence compared with pathogens control
treatments. The pathogen F. oxysporum treatments with T. harzianum (TF) showed
that all the treatments (TF) achieved high germination rate for eggplant seeds
compared with control treatment, while the treatment TF13 was significantly
superior than all other treatments in number of leaflets, stem height, shoot fresh
weight, shoot dry weight, root fresh weight, root dry weight and root size which
recorded 8.67, 19.00cm, 20.33gm, 4.73gm, 12.00gm, 1.53gm, 17.67cm³
respectively.
The present study was conducted to induce mutations by UV- light in Trichoderma harzianum for tolerance of Bavistin fungicides which are commonly used to control soil born phytopathogens. The mycelium growth of T. harzianum T1, T2 was inhibited completely by 30 μg (a.i.) /ml PDA of Bavistin. Two isolates of Trichoderma harzianum T1 and T2 conidia suspensions 104 conidia / ml were irradiated by UV lights at 254, 320, 365nm wavelength for 10, 20, 40, 80, 160 min using UV dark room cabinet and spectrophotometer and cultured on PDA media containing 50, 60, 75, 100, and 150 μg (a.i) / ml Bavistin. A thirty one unstable mutants tolerant to Bavistin were obtained after irradiation the T. harzianum T1, T2 conidia suspension 104 conidia / ml by
... Show MoreThis study includes isolation, purification, and identification of Fusarium oxysporum from chili pepper infected plants. Eucalyptus camaldulensis were collected and air dried at room temperature, then ground to semi powdered state. Phenols, alkaloids and terpens were extracted from Eucalyptus camaldulensis. The antifungal activity, type of extracts was evaluated at different concentrations 5 and 10 mg / ml of these compounds were prepared and their antagonistic activity was studied. The Percentage of radial growth inhibition of fungi by plant extracts was measured after 7 day incubation. Results showed that terpens extract was the most active against fungi and alkaloids extract had less antifungal activity and the percentage of mycelia r
... Show MoreIndole acetic acid (IAA) produced from F. oxysporum (F2) was purified by several steps included extraction by cold ethyl acetate ; Column chromatography using silica gel and TLC chromatography . The pure indole acetic acid (IAA) which produce by F. oxysporum (IAA) was tested by ultraviolet spectra at (200-300)nm ; and appear that the maximum absorbance at 229nm , the high performance liquid chromatography (HPLC) used to test the purity of the indole acetic acid and the results showed one peak at appearance time 3.822 min
Saccharomyces cerevisiae filtrate showed inhibitory effect against Fusarium spp. when grow in a liquid medium (Sabouraud) with different concentrations (1, 3, 5) %. The higher inhibitory effect against fungus growth was (24.5) mm at (5%) in PDA medium compared with control (36.5) mm during the seventh day propagation. The filtrate of Lactobacillus plantarum isolate was mixed with the PDA medium ,which showed inhibitory effect against Fusarium spp. The concentrated filtrate( one fold) appcarcd a higher effect against the same fungus compared with un concentrated filtrate one. Saceharomyces cerevisiae and Lactobacillus plantarum
... Show MoreResearch was conducted to study the effect of proline and aspirin with 10 and 20 ppm on seed germination and seedling growth of Lycopersicon esculentumand the effect of surface growthof Fusarium oxysporum.The results showed that the proline and aspirin effected significantly to decreased percentage of seed germination, acceleration of germination, promoter indicator, elongation speed of radical and plumule and also the infection percentage of seed decay and surface growth of Fusarium oxysporumwas reduced significantly.
Eighty one bacterial isolates were obtained from 53 soil samples of different plants rhizosphere. All the isolated bacterial were screened for antifungal effect against Fusarium oxysporum . Three isolates gave antifungal activity with inhibition zone ranged between (0.5-2.5 cm). Two isolates (Bd1 and Bd2) were Brevundimonas diminuta, while the third (Pf1) was Pseudomonas fluorescence . B. diminuta (Bd1) which used in this study isolated from Raphanus sativus gave the highest inhibition zone against F. oxysporum. Cell free supernatant of B.diminuta(Bd1) was better in antifungal activity than bacterial cells against F. oxysporum. The highest antifungal substance production was obtained from mineral salt broth containing 1% peptone after in
... Show MoreAbstract The present study was Conducted to evaluate the effect of amixture of three species of arbuscular mycorrhizal fungi ( Glomus etunicatum , G. leptotichum and Rhizophagus intraradices ) in inducing the non-enzymatic antioxidants of tomato roots infected with Fusarium oxysporum f.sp. Lycopersici wich cause Fusarial wilt disease , and planted for 10 weeks in the presence of the organic matter ( peatmose) , using pot cultures in aplastic green house , Results indicated significant reduction of disease incidence percentage and infection rate of roots infected with the pathogen 4 weaks after mycorrhizal colonization in all treatments ( single , dual and trial interactions) . on the other hand mycorrhizal colonization of the roots in the
... Show MoreThe experiment was conducted to study the effect of
antigibberellin Cultar , Ethephon and GA3 at concentration of (5,15,25 ppm) on surface growth of Rhizoctiona solani and Fusraium oxysporum . The results indicated that Cultar (15 , 25 ppm) decreased the surface growth of both fungi . Ethephon of the same concent
... Show MoreThe main aim of this study was to molecular identification and determine the antagonistic impact of rhizosphere Trichoderma spp. against some phytopathogenic fungi, including (Magnaporthe grisea) pyricularia oryzae, Rhizoctonia solani and Macrophomina phasolina. Four Trichoderma isolates were isolated from rhizosphere soils of the different host plants in different locations of Egyptian governorates. The morphological characterization of isolated Trichoderma as well as using of (ITS1-5.8S-ITS2) ribosomal gene sequence acquisition and data analyses. By comparing the results of DNA sequences of ITS region, the fungi represented one isolate were positively identified as T. asperellum (1 isolate T1) and one as T. longibrachiatum (1 isolate T2)
... Show MoreThe study included isolate and diagnose fungus Fusarium solani of the local soil and purified and development in the PDB medium and the filtrate extracted using a solvent (Ethyl acetate) to obtain the fungal secondary metabolites extract. This extract has shown bioactivity against both reference isolates (E.coli (ATCC25922) and S.aureus(NCTC6571)) and pathogenic isolates S.pyogenes, K. pneumonia and S.typhimurium using agar disk diffusion technique , The diameters of the inhibition zones of fungal secondary metabolites24.0 mm against E.coli and 31.5 mm against S.aureus,and 34.0 mm against K.pneumoniae and 18.0 mm against S.pyogenes and 33.5mm against S.typhimurium. The test revealed the minimum inhibitory concentration (MIC) of the fungal
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