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1.
Sci Rep ; 14(1): 1874, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253713

RESUMO

Identifying a viable substitute for the limited array of current antifungal agents stands as a crucial objective in modern agriculture. Consequently, extensive worldwide research has been undertaken to unveil eco-friendly and effective agents capable of controlling pathogens resistant to the presently employed fungicides. This study explores the efficacy of Trichoderma isolates in combating tomato leaf spot disease, primarily caused by Alternaria alternata. The identified pathogen, A. alternata Alt3, was isolated and confirmed through the ITS region (OQ888806). Six Trichoderma isolates were assessed for their ability to inhibit Alt3 hyphal growth using dual culture, ethyl acetate extract, and volatile organic compounds (VOCs) techniques. The most promising biocontrol isolate was identified as T. afroharzianum isolate TRI07 based on three markers: ITS region (OQ820171), translation elongation factor alpha 1 gene (OR125580), and RNA polymerase II subunit gene (OR125581). The ethyl acetate extract of TRI07 isolate was subjected to GC-MS analysis, revealing spathulenol, triacetin, and aspartame as the main compounds, with percentages of 28.90, 14.03, and 12.97%, respectively. Analysis of TRI07-VOCs by solid-phase microextraction technique indicated that the most abundant compounds included ethanol, hydroperoxide, 1-methylhexyl, and 1-octen-3-one. When TRI07 interacted with Alt3, 34 compounds were identified, with major components including 1-octen-3-one, ethanol, and hexanedioic acid, bis(2-ethylhexyl) ester. In greenhouse experiment, the treatment of TRI07 48 h before inoculation with A. alternata (A3 treatment) resulted in a reduction in disease severity (16.66%) and incidence (44.44%). Furthermore, A3 treatment led to improved tomato growth performance parameters and increased chlorophyll content. After 21 days post-inoculation, A3 treatment was associated with increased production of antioxidant enzymes (CAT, POD, SOD, and PPO), while infected tomato plants exhibited elevated levels of oxidative stress markers MDA and H2O2. HPLC analysis of tomato leaf extracts from A3 treatment revealed higher levels of phenolic acids such as gallic, chlorogenic, caffeic, syringic, and coumaric acids, as well as flavonoid compounds including catechin, rutin, and vanillin. The novelty lies in bridging the gap between strain-specific attributes and practical application, enhancing the understanding of TRI07's potential for integrated pest management. This study concludes that TRI07 isolate presents potential natural compounds with biological activity, effectively controlling tomato leaf spot disease and promoting tomato plant growth. The findings have practical implications for agriculture, suggesting a sustainable biocontrol strategy that can enhance crop resilience and contribute to integrated pest management practices.


Assuntos
Acetatos , Alternaria , Hypocreales , Cetonas , Solanum lycopersicum , Peróxido de Hidrogênio , Etanol
2.
Sci Rep ; 12(1): 16468, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183011

RESUMO

One of the tomato's acutely devastating diseases is Alternaria leaf spot, lowering worldwide tomato production. In this study, one fungal isolate was isolated from tomatoes and was assigned to Alternaria alternata TAA-05 upon morphological and molecular analysis of the ITS region and 18SrRNA, endoPG, Alt a1, and gapdh genes. Also, Urtica dioica and Dodonaea viscosa methanol leaf extracts (MLEs) were utilized as antifungal agents in vitro and compared to Ridomil, a reference chemical fungicide. The in vitro antifungal activity results revealed that Ridomil (2000 µg/mL) showed the highest fungal growth inhibition (FGI) against A. alternata (96.29%). Moderate activity was found against A. alternata by D. viscosa and U. dioica MLEs (2000 µg/mL), with an FGI value of 56.67 and 54.81%, respectively. The abundance of flavonoid and phenolic components were identified by HPLC analysis in the two plant extracts. The flavonoid compounds, including hesperidin, quercetin, and rutin were identified using HPLC in D. viscosa MLE with concentrations of 11.56, 10.04, and 5.14 µg/mL of extract and in U. dioica MLE with concentrations of 12.45, 9.21, and 5.23 µg/mL, respectively. α-Tocopherol and syringic acid, were also identified in D. viscosa MLE with concentrations of 26.13 and 13.69 µg/mL, and in U. dioica MLE, with values of 21.12 and 18.33 µg/mL, respectively. Finally, the bioactivity of plant extracts suggests that they play a crucial role as antifungal agents against A. alternata. Some phenolic chemicals, including coumaric acid, caffeic acid, ferulic acid, and α-tocopherol, have shown that they may be utilized as environmentally friendly fungicidal compounds.


Assuntos
Fungicidas Industriais , Hesperidina , Sapindaceae , Solanum lycopersicum , Urtica dioica , Alternaria , Antifúngicos/farmacologia , Ácidos Cumáricos , Metanol , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Quercetina , Rutina , Urtica dioica/química , alfa-Tocoferol
3.
Clin Pract Epidemiol Ment Health ; 18: e174501792208200, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37274863

RESUMO

Background: This great pandemic of COVID-19 has been a unique stressor that affected all communities in 2020. This study aims to examine the prevalence of anxiety and depression due to the COVID-19 pandemic in Saudi Arabia and to study the emotional cognition scale in the Kingdom of Saudi Arabia (KSA) in relation to the COVID-19 pandemic. Methodology: A descriptive cross-sectional study was conducted on 857 inhabitants randomly selected from the 13 administrative regions of Saudi Arabia, using a validated self-administrated questionnaire comprising six sections. The collected data were summarized and analyzed. Results: Among the majority of the studied participants, 377 (44.0%) were aged from 35 to less than 50 y. There were 489 (57.1%) females and 368 (42.9%) males, 616 (71.9%) Saudi nationals, 715 (83.4%) university-educated or postgraduate, 619 (72.2%) unmarried and 238 (27.8%) married, and 663 (77.4%) living in areas under partial lockdown. The resultant elevated total depression score was statistically significant (p<0.05) for the following: participants younger than 35y, females, Saudis, those with lower education levels, those who were married, students, those with work suspension during the COVID-19 pandemic, and amongst those who experienced complete lockdown. Among the majority of the studied participants, 355 (41.2%) showed mild depression, and 281(32.6) showed moderate anxiety, and were in the growth zone. In addition, the elevated total anxiety score was statistically significant (p<0.05) amongst the following; younger participants, females, Saudi nationals, those with lower educational levels, those who were unmarried, students, those with telework, and those with no curfew. Conclusion: The adverse mental health effects were more prevalent among particular groups of the population, such as females, adults under 35 years old, students, those with lower educational attainments, and those suffering from chronic illnesses. Anxiety was significantly correlated with depression. The practice of preventive measures, e.g., wearing masks, and social distancing to prevent the spread of COVID-19, may have had psychological benefits during the pandemic. Summary: We assessed the mental health status in Saudi Arabia during the first wave of the COVID-19 pandemic. Mild depression and moderate anxiety were prevalent problems, with many determinants and interrelations. Fear was the most infectious emotion, while happiness was the highest.

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