Management of coriander stem rot caused by Sclerotinia sclerotiorum using certain biocontrol agents and chemical inducers

The aim of the present study was to evaluate certain of bioagents (Trichoderma harzianum, T. hamatum, T. viride and ESRU bioformulation) and chemical inducers (salicylic acid and potassium silicate) on suppression of coriander stem rot disease caused by Sclerotinia sclerotiorum. The highest antagonistic bioagent was T. viride which reduced the mycelial growth to 3.9 cm in relation to control, being (9.0 cm). Moreover, five concentrations of each of salicylic acid and potassium silicate (0, 100, 250, 500 and 750 ppm) were evaluated against the growth and formation of sclerotia of the causal fungus in vitro and in a greenhouse. Salicylic acid completely inhibited both parameters at 250 and 500 ppm., respectively. Meanwhile, potassium silicates gave the same effect at 750 ppm. Under greenhouse conditions, spraying of coriander plants challenged with the causal fungus with any of the tested inducers and the bioagents lead to a critical reduction in the disease severity in relation to the control. Potassium silicate and salicylic acid as well as T. viride and ESRU formulation were the most efficient treatments, being 18.52, 22.22, 29.63 and 33.33%, respectively. Moreover, the effect of the tested inducers as a soil drench integrated with the bioagents as foliar spray was performed. Potassium silicate integrated with T. viride was the most effective treatment. Two season field experiments (2015-2016 and 2016-2017) showed that potassium silicate as soil drench integrated with T. viride as foliar spray was highly effective in reducing the percentage of dead plants and the area under the disease progress curve as well as increasing the weight of 100 seeds during the two seasons. An increase in the activity of polyphenoloxidase, peroxidase and phenylalanine ammonia lyase was recorded in the leaves sprayed with potassium silicate followed by those sprayed with salicylic acid then T. viride and the ESRU formulation.

In Silico Study for Similar FDA Approved Drugs as Inhibitors of SARS-CoV-2 Spike and the Host Receptor Proteins

The severe acute respiratory syndrome coronavirus 2, known as COVID-19, has been hideously increased worldwide. The disease began in Wuhan, China, around December 2019, then spread to most countries. Social distancing is the best procedure to prevent infection. Screening the available database containing millions of drug molecules or phytochemicals has become rapid and straightforward because of the computer-aided drug design (CADD) methods. In the present study, 300 phytochemicals and cellulose ether derivatives are screened through a docking study. Docking analysis showed that only four molecules (a-neohesperidin, quercetin 3-O-glucosylrutinoside, 14-ketostypodiol diacetate, and hydroxypropyl methylcellulose) were able to interact with the spike protein. However, two among them (quercetin 3-O-glucosylrutinoside and 14-ketostypodiol diacetate) could interact with the host cell receptor (ACE2) of SARS-CoV-2. The binding affinity of the four compounds is high. Still, according to Lipinski's rule of five, only 14-ketostypodiol diacetate was selected as a drug molecule due to its pharmacokinetic and ADMET properties. Screening for drug analogs to the 14-ketostypodiol diacetate detected five approved drugs. Docking analysis of these drugs with the target proteins showed that the five drugs interact with the host receptor protein, and three interact with viral spike protein. Accordingly, we suggest that molecular docking and drug analogs studies could support rapid drug development. In addition, future perspectives on therapeutic applications of 14-ketostypodiol diacetate are required for using it against SARS-CoV-2 infections

Mitigation of Powdery Mildew Disease by Integrating Biocontrol Agents and Shikimic Acid with Modulation of Antioxidant Defense System, Anatomical Characterization, and Improvement of Squash Plant Productivity

Squash (Cucurbita pepo L.) is a globally important vegetable, the production of which is severely constrained by powdery mildew caused by Podosphaera xanthii. In this study, we examined the effects of Trichoderma asperellum (MW965676), Streptomyces rochei (MN700192), and a mixture of the two foliar sprays with or without shikimic acid seed priming treatment on powdery mildew severity, plant growth, and total yield during the 2020–2021 and 2021–2022 growing seasons. We also studied their immune eliciting properties by examining their enzymatic, phenolic, and hormonal functions. The combination of Trichoderma asperellum, Streptomyces rochei, and shikimic acid triggered plant defense responses, which elicited enzyme activities such as peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), phenolic compound accumulation, and increased salicylic acid (SA) and jasmonic acid (JA) content. This approach yielded high-quality results in the control of powdery mildew during the two growing seasons under greenhouse conditions. Additionally, relatively large statistical differences in plant growth, total yield, mineral components, and physiological traits were observed. A GC–MS analysis of Trichoderma asperellum (MW965676) showed hemin cation as a major component, while Streptomyces rochei (MN700192) contained 2,4-di-tert-butyl phenol and the hexadecenoic acid methyl ester. With respect to the morphological changes induced by powdery mildew and the treatments, plants treated with a mixture of Trichoderma asperellum, Streptomyces rochei and shikimic acid showed an improvement in the thickness of the midvein, increased dimensions of the main midvein bundle, a larger number of xylem rows in the main midvein bundle, greater mean diameters of vessels and of parenchyma cells in the ground tissues, as well as increased thickness of the upper and lower epidermis, lamina, palisade tissue and spongy tissue. This extensive, new study is the first step toward a more profound understanding of the use of Trichoderma asperellum and Streptomyces rochei with shikimic acid-primed seeds as a potential alternative technique for attenuating powdery mildew infection in squash

Mitigation of Powdery Mildew Disease by Integrating Biocontrol Agents and Shikimic Acid with Modulation of Antioxidant Defense System, Anatomical Characterization, and Improvement of Squash Plant Productivity

Squash (Cucurbita pepo L.) is a globally important vegetable, the production of which is severely constrained by powdery mildew caused by Podosphaera xanthii. In this study, we examined the effects of Trichoderma asperellum (MW965676), Streptomyces rochei (MN700192), and a mixture of the two foliar sprays with or without shikimic acid seed priming treatment on powdery mildew severity, plant growth, and total yield during the 2020–2021 and 2021–2022 growing seasons. We also studied their immune eliciting properties by examining their enzymatic, phenolic, and hormonal functions. The combination of Trichoderma asperellum, Streptomyces rochei, and shikimic acid triggered plant defense responses, which elicited enzyme activities such as peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), phenolic compound accumulation, and increased salicylic acid (SA) and jasmonic acid (JA) content. This approach yielded high-quality results in the control of powdery mildew during the two growing seasons under greenhouse conditions. Additionally, relatively large statistical differences in plant growth, total yield, mineral components, and physiological traits were observed. A GC–MS analysis of Trichoderma asperellum (MW965676) showed hemin cation as a major component, while Streptomyces rochei (MN700192) contained 2,4-di-tert-butyl phenol and the hexadecenoic acid methyl ester. With respect to the morphological changes induced by powdery mildew and the treatments, plants treated with a mixture of Trichoderma asperellum, Streptomyces rochei and shikimic acid showed an improvement in the thickness of the midvein, increased dimensions of the main midvein bundle, a larger number of xylem rows in the main midvein bundle, greater mean diameters of vessels and of parenchyma cells in the ground tissues, as well as increased thickness of the upper and lower epidermis, lamina, palisade tissue and spongy tissue. This extensive, new study is the first step toward a more profound understanding of the use of Trichoderma asperellum and Streptomyces rochei with shikimic acid-primed seeds as a potential alternative technique for attenuating powdery mildew infection in squash

Correction: Omar et al. Antifungal Evaluation and Molecular Docking Studies of Olea europaea Leaf Extract, Thymus vulgaris and Boswellia carteri Essential Oil as Prospective Fungal Inhibitor Candidates. Molecules 2021, 26, 6118

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