https://www.journals.psmpublishers.org/index.php/ijmm/issue/feed International Journal of Molecular Microbiology 2019-09-16T04:32:22+00:00 International Journal of Molecular Microbiology ijmm@psmpublishers.org Open Journal Systems <p>International Journal of Molecular Microbiology (IJMM; ISSN: 2617-7633) is a peer-reviewed, open access, international scientific journal that publishes research on all aspects of molecular microbiology.</p> https://www.journals.psmpublishers.org/index.php/ijmm/article/view/296 Antagonistic Potential of Native Trichoderma species against Tomato Fungal Pathogens in Yemen 2019-09-15T15:30:04+00:00 Nesreen A Al-Mekhlafi omamrmalik@yahoo.com Qais Y Abdullah drqaisabdullah@gmail.com Mohammed F Al-Helali mohammedf.al-helali@yahoo.com Saeed M Alghalibi alghlibi@gmail.com <p style="text-align: justify;">The present study was conducted to determine the antagonistic potential of native <em>Trichoderma </em>species against tomato fungal pathogens in Yemen. A total of 200 rhizosphere soil samples of different crops (sorghum, corn and potato) were collected from different provinces in Yemen (Ibb, Sana'a, Taiz, Amran, Thamar and Al-Hodaida) and screened for the presence of <em>Trichoderma</em> species isolates and their antifungal activity against four pathogenic fungi (<em>A. solani</em>, <em>F. oxysporum</em>, <em>P. ultimum</em> and <em>R. solani</em>) using dual culture technique. Thirteen <em>Trichoderma</em> species were identified among a total of 96 <em>Trichoderma</em> isolates. <em>T. harzianum</em> (33.33%) was the most predominant species occurring in the present soil samples. <em>Trichoderma </em>species showed the ability to grow in the moisture content of the soil ranging from 12.28% to 23.49% and pH values ranging from 7.16 to 7.88. Results showed that antagonistic potential of <em>Trichoderma</em> isolates varied significantly which inhibited the growth of the pathogen isolates at varying degrees. Among the isolates of <em>Trichoderma</em>, only 16 isolates showed strong antagonistic activity and inhibited four pathogenic fungi by more than 50%. These potential isolates of <em>Trichoderma</em> may be further exploited as biocontrol agent against soilborne pathogenic fungi.</p> 2019-04-30T00:00:00+00:00 Copyright (c) 2019 PSM https://www.journals.psmpublishers.org/index.php/ijmm/article/view/303 Aflatoxins and Ochratoxin A Content of Stored Yemeni Coffee Beans and Effect of Roasting on Mycotoxin Contamination 2019-09-15T00:50:47+00:00 AbdelRahman A.H. Humaid humaidyemen@gmail.com Saeed M.S. Alghalibi alghalibi@gmail.com Eshraq Ahmed Ali Al- Khalqi eshraqyemen@yahoo.com <p>This study was aimed to determine the natural occurrence of ochratoxin A (OTA) and total aflatoxins (B<sub>1</sub>, B<sub>2</sub>, G<sub>1,</sub> and G<sub>2</sub>) (AFs) of stored Yemeni green and roasted coffee beans. A total of 50 samples (25 samples each) were collected randomly from different markets in Sana'a city, Yemen during 2013, and quantitative assessment of these two types of mycotoxins was done using ELISA test kits. In addition, the influence of roasting on OTA and AFs contamination of green coffee beans was also investigated using the pan roasting method. Our results showed that all green and roasted coffee bean samples examined were contaminated with OTA, at concentrations ranging from 1.114 to 18.667 ppb and 1.646 to 31.077 ppb respectively. Also, all green and roasted coffee bean samples examined were contaminated with AFs, at concentrations ranging from 14.694 to 27.176 ppb and 14.255 to 23.231 ppb respectively. In addition, the roasting of contaminated green coffee bean samples with different concentrations of OTA and AFs reduced OTA and AFs levels to 86% and 20% from the initial concentration, respectively. These results indicate that there are risks of mycotoxin contamination of stored Yemeni green and roasted coffee beans.</p> 2019-04-30T00:00:00+00:00 Copyright (c) 2019 PSM https://www.journals.psmpublishers.org/index.php/ijmm/article/view/304 Trichoderma: a Potential Biocontrol Agent for Soilborne Fungal Pathogens 2019-09-16T04:32:22+00:00 Muhammad Naeem Iqbal driqbalnaeem@hotmail.com Asfa Ashraf sundausnaeem@yahoo.com <p><strong>EDITORIAL</strong></p> <p>Plants are susceptible to diseases with far-reaching economic implications. Infections with phytopathogenic fungi are among the most worrying of these diseases as it may result in significant crop yield losses. Some of the fungi produce potentially toxic compounds which can be harmful to human beings if they are ingested via consumption of contaminated food (Ferre, 2016; Suprapta, 2012). The soil is a rich collection of organisms which have multifaceted roles in the ecological dynamics (Siyar<em> et al.</em>, 2019). The growing concern about the hazards involved relating to human health and environmental contamination has led to a demand for the development of alternatives to control plant diseases (Alsohiby<em> et al.</em>, 2016; Iqbal and Ashraf, 2017).</p> <p>In general, the control of fungal phytopathogens is achieved by applying synthetic fungicides. However, their use has led to problems for the environment and human and animal health (Nunes, 2012), as well as fear-mongering by some opponents of pesticides, has led to considerable changes in people’s attitudes towards the use of pesticides in agriculture. The growing concern about the hazards involved relating to human health and environmental contamination has led to a demand for the development of alternatives to control plant diseases (Carmona-Hernandez<em> et al.</em>, 2019).</p> <p>One of the major challenges encountered during the selection of biocontrol agents is that biocontrol agents that appear efficacious based on&nbsp;<em>in vitro</em>&nbsp;experiments might not be effective in controlling plant diseases in greenhouse or field conditions. The appropriate application method is likely to contribute significantly to the success of the biocontrol agents in the field trials (Suprapta, 2012).</p> <p>In this issue, (Al-Mekhlafi<em> et al.</em>, 2019) investigate the antagonistic potential of native <em>Trichoderma</em> species against tomato fungal pathogens. Results showed that antagonistic potential of <em>Trichoderma</em> isolates varied significantly which inhibited the growth of the pathogen isolates at varying degrees. Among the isolates of <em>Trichoderma</em>, only 16 isolates showed strong antagonistic activity and inhibited four pathogenic fungi by more than 50%. These potential isolates of <em>Trichoderma</em> may be further exploited as biocontrol agent against soilborne pathogenic fungi.</p> <p>Therefore, they are excellent candidates as biocontrol agents for the biological control. In order to establish&nbsp;<em>Trichoderma </em>as biocontrol agents, more field experiments should be conducted to determine their control efficacy under different environmental conditions. Additionally, more work is needed to optimize isolation, formulation and application methods of&nbsp;<em>Trichoderma</em>&nbsp;in order to fully maximize their potential as effective biocontrol agents. In recent years, there has been an advance in the use of molecular techniques that contribute to improving the knowledge of antagonistic mechanisms.</p> 2019-04-30T00:00:00+00:00 Copyright (c) 2019 PSM