عزل وتشخيص الفطريات المرافقة لزراعة الفطر الغذائي الأبيض Agaricus bisporus وإمكانية مكافحتها

Isolation and identification of fungi associated with the cultivation of the white edible mushroom Agaricus bisporus and the possibility to

This study was conducted in the laboratories and cultivation rooms of the Plant Protection Department of the College of Agriculture – University of Karbala in the agricultural season 2021-2022 with the aim of identifying the most important fungal pathogens and fungal competitions accompanying the cultivation of the edible food mushroom Agaricus bisporus in Iraq, Molecular diagnosis and study of its effects on production and the possibility of control using some plant extracts (cloves, conocarpus, turmeric, dracaena, eucalyptus and black seed) and agricultural pesticides (The biopesticide Verox, the chemical pesticide Benomyl, the botanical pesticide Tondixer, and the biological product Seaboolm). The results Showed of isolation and identification of fungi associated with cases of infection in the breeding of the edible white fungus Agaricus bisporus, which were collected from different breeding stations of edible fungi from five governorates namely Baghdad, Diwaniyah, Erbil, Kirkuk and Muthanna showed the presence of different species belonging to the following fungal genera Aspergillus spp. , Fusarium spp. , Mucor spp, Penicillium spp., Verticillium spp., Rhizopus spp., Alternaria spp. and Trichoderma spp. The results of testing its pathogenicity against the growth of the edible white mushroom A. bisporus in the vitro on Compost agar medium (CAM) showed that there were some significant differences between the ability of the tested fungal isolates in terms of their effect on the growth percentage of edible mushrooms, as the fungus Trichoderma harzianum isolated from Erbil governorate was recorded the highest percentage of inhibition was 75%. Both Aspergillus flavus isolated from Baghdad governorate and Mucor circinelloides isolated from Erbil governorate recorded an inhibition rate of 66.66% , The two fungi Aspergillus ochraceus isolated from Diwaniyah province and the fungus Penicillium citrinum isolated from Baghdad province recorded an inhibition rate of 58.33%, while the fungus Aspergillus terreus recorded an inhibition rate of 50%. The phenotypically isolated fungal isolates were diagnosed based on their microscopic characteristics, and the molecular diagnosis of six fungal isolates that showed great antagonism was done by analyzing the DNA base sequences of the ITS. And by sequencing the nitrogenous bases of these isolates, it was found that they are genetically different from other isolates diagnosed in the National Center for Biotechnology Information (NCBI), and therefore they were registered under the accession numbers ON738705.1, ON738706.1, ON738707.1, ON738708.1,ON738710.1and ON925001 for isolates (Aspergillus flavus, Aspergillus ochraceus, Aspergillus terreus, Mucor circinelloides, Penicillium citrinum and

Trichoderma harzianum) respectively and comparison of each isolate with globally identified isolates in the genebank. Laboratory experiments showed that all tested plant extracts inhibited the growth of pathogenic fungal isolates and white edible mushrooms at a different percentage. The clove and Conocarpus extracts were distinguished by the highest percentage of inhibition. The clove extract recorded an inhibition rate of 71.5%, and Conocars extract reached 68.4%. While it showed the efficiency of agricultural pesticides in inhibiting the growth of the most virulent fungal isolates. The biocide Verox recorded the highest rate of inhibition of pathogenic fungal isolates by 78.7%. While the combination of Verox with extracts of cloves and Conocarpus showed the highest rate of inhibition by 77.9% compared to the control treatment 0.00%, and the percentage of growth inhibition of the white fungus was 38.1% compared to the control treatment 0.00% laboratory. The experiment was conducted in the cultivation room to investigate the effect of pathogens (A.flavus-B1, A.ochraceus-D1, A.terreus-K1, P.citrinum-B1, T.harzianum-E1, M.circinelloides-E1) on Some growth parameters of the edible white mushroom A. bisporus, All tested pathogens caused a significant reduction in the number of formed fruit bodies, their average weight, cap diameter and stem length, as well as the effect of the causes was reflected on the nutritional content of the fruit bodies of elements (nitrogen and phosphorous, potassium, sodium) and total protein. While the agents used (Clove extract, Conocarpus extract, and Verox biocidal) and their combination showed effective efficiency in inhibiting the effect of pathogens and increasing some growth parameters of Agaricus bisporus. The results showed the superiority of the treatment of the combination of the biocide verox with extracts of cloves and Conocarpus in inhibiting the effect of pathogenic fungi, as it recorded the highest rate in the number of fruiting bodies which reached 505, 515, 540, 435, 500 and 405 bodies / m2 for fungi (A.flavus-B1, A.ochraceus-D1, A.terreus-K1, P.citrinum-B1, T.harzianum-E1 and M.circinelloides-E1) compared to the comparison treatment, which gave (195, 170, 240, 140, 125, and 180) bodies/ m2 respectively, for the aforementioned fungi While the number of fruiting bodies in the control treatment was 580 bodies / m2 respectively. This was followed by the treatment of the plant extract of cloves at a rate of (350, 355, 410, 285, 330, and 290) bodies/ m2, then the treatment of the plant extract of Conocaris at a rate of (385, 360, 350, 330, 235, and 295) bodies/ m2, and finally the treatment with Verox at a rate of (310, 315, 355, 340, 240, and 255). fruiting body / m2 respectively The results proved the same on the amount of yield, as the results showed that the combination treatment between the biocide verox with extracts of cloves and conocarpus was
superior in increasing the amount of the final yield, as it recorded the highest rate (19.894, 20.289, 21.603, 16.398, 19.118, and 17.07) kg/m2 Compared to the rate of treating the pathogen (A.flavus-B1, A.ochraceus-D1, A.terreus-K1, P.citrinum-B1, T.harzianum-E1, M.circinelloides-E1), which gave a rate of (4.933, 4.364, and 6). .495, 3.343, 2.603, and 4.741) kg/m2, while the amount of final yield in the control treatment was 23.376 kg/m2, followed by the treatment of cloves plant extract with a rate of (11.414, 11.395, 13.655, 9.194, 11.389,9). 775) kg/m2, then the treatment of the plant extract of Conocaris at a rate of (13.951, 12.546, 12.011, 11.283, 7.264, and 10.136) kg/m2, and finally the treatment with Verox at a rate of (11.105, 11.453, 12.264, 11.606, 8.029, and 8.576). kg/m2, respectively.