Isolation, Morphological and Molecular Identification of the Pathogenic and Competitors Fungi Associated with the Edible Mushroom Pleurotus sp. and Control Them

Abstract

Eleven fungal isolates were isolated from oyster mushroom culture media. 10 isolates showed antagonistic activity against P. pulmonarius, while two fungal isolates did not show any antagonistic activity. the highest pathogenic fungi were identified as T. longibrachiatum, T. pleuroticola, R. arrhizus, M. hiemalis and P. glabrum according to the morphological and molecular methods and were registered in the World Genetic Bank at NCBI with the accession numbers OM438162.1, OM438163.1, OM438161.1, OM453951.1 and OM438160.1, respectively, the species T. pleuroticola, R. arrhizus and M. hiemalis were recorded for the first time in Iraq at the molecular level. The effect of some oils on the growth of the oyster mushroom P. pulmonarius and its pathogenic fungi was studied, the results showed that the highest effect of jojoba oil, olive oil, almond oil, sesame oil and coconut oil at 5% was recorded the highest inhibition of the all tested pathogenic fungi, while no inhibitory effect was recorded for the oyster mushroom P. pulmonarius. Sodium bicarbonate at 3 and 5% showed complete inhibition of the growth of all pathogenic fungi. The results showed that 5% of acetic acid inhibits the pathogenic fungi T. longibrachiatum, R. arrhizus and T. pleuroticola, where the diameters of the colonies reached 2.5, 2.7 and 3.1 cm. respectively. The highest biological efficiency was recorded in P. eryngii growing in the medium treated with the pathogenic fungus P. glabrum in presence of sodium bicarbonate, which reached to 69.58%. In the interaction between oyster mushroom species and the media, the results showed that the highest infection rate was in P. eryngii in the medium treated with T. longibrachiatum, which reached to 39.56%, while the lowest infection rate was with P. pulmonarius grown in the medium treated with sodium bicarbonate and the pathogenic fungus P. glabrum, which was 13.15%. Under the pathogens infection, the highest protein content was found in P. eryngii grown in the treated medium with sodium bicarbonate and P. glabrum resulting in 31.22%, while the lowest protein was12.07%. in P. ostreatus grown in the medium infected with T. longibrachiatum.

Isolation, Phenotypic and Molecular Characterization of the Oyster Mushroom Pleurotus spp. and Evaluation of Its Efficacy in Producing the Antibiotic Pleurotin

“…The results of the isolated Pleurotus spp. diagnosis revealed a high percentage of similarity in the nucleotide sequences of the 5.8 S rRNA gene with the nucleotide sequences of the globally recorded fungi with a range of 99.11-99.20%, which confirms the accuracy of the diagnosis of these fungi, although there is a similarity to the isolates of the fungi isolated in this study in the conformity of the nucleotide sequences, but they are considered genetically different isolates, the reason for this may be due to the sexual reproduction and mutations as a result of their presence in different habitats , in addition to being exposed to different environmental conditions [25,28]. The results of the effect of the culture media used in the production of pleurotin showed a variation in the effect of the type of culture medium on the concentration of pleurotin, which may be due to the fact that the components of the culture media play an important role in the growth of the fungus and the production of pleurotin.…”

Mycosynthesis of Copper Nanoparticles by Aspergillus spp. Isolated from the Tomato Rhizosphere and Evaluating their Inhibition Efficacy on the Pathogenic Fungus Fusarium oxysporum

“…Molecular diagnosis of Aspergillus spp. showed a high similarity in the nucleotide sequences of the 5.8 S rRNA gene with the nucleotide sequences of the fungi recorded in NBCI with a range of 98.07 -99.25%, although there is a similarity to the fungal isolates but they are considered genetically different at 0.75-1.93% , the reason for this may be due to mutations as a result of these isolates live in different habitats , which exposed to various environmental conditions [17,18] Cupric oxide (CuO) nanoparticles have shown promising results as antifungal agents due to their unique physicochemical properties. These nanoparticles have a high surface area to volume ratio, which increases their contact with fungal cells and improves their efficacy.…”

Isolation, Identification and Cultivation of Ganoderma spp. and Evaluation of Their Efficiency in Inhibiting Plant Pathogenic Fungi Fusarium oxysporum and Alternaria tenuissima

“…Encouraging the growth and increase of yield and protein content in some mushrooms were recorded in the previous studies such as G. resinaceum [9], Pleurotus spp. [26][27][28][29] and Agaricus bisporus [30,31] . Not all of the supplements are suitable for the growth of mushrooms.…”