The inhibitory potential of chitinolytic Trichoderma spp. was assayed against Meloidogyne incognita in vitro and in vivo. Sixteen Trichoderma isolates were assayed for chitinase activity using basal solid medium supplemented with colloidal chitin. Isolates recorded high chitinolytic activity were identified morphologically as Trichoderma asperelloides, T. hamatum, T. harzianum and T. viride. The four species were quantitatively assayed for total and specific chitinase activity. T. asperelloides showed maximum chitinase activity (1.736 U/mL). In vitro studies revealed that egg hatching and second juveniles vitality of root-knot nematodes were significantly inhibited by chitinase-containing growth culture of the four selected chitinolytic Trichoderma species. However, the reduction effect was directly correlated with the concentration of fungal growth suspension. Under greenhouse conditions, three sequentially treatments of soil with homogenized culture suspension were studied. Trichoderma species significantly reduced the final nematode population by 97.81% and root galling by 92.81%. Moreover, all tested Trichoderma species obviously promoted tomato growth compared to untreated control. Significant positive correlation between the biocontrol efficacy of Trichoderma species against root-knot nematodes and their chitinolytic activity was confirmed. The most potential chitinolytic species, T. asperelloides, also recorded the highest biocontrol activity against M. incognita.

Background: Tomato )Solanum lycopersicum( is one of the most popular vegetable crops in Egypt. It is affected by a wide range of pests; prominent among them is root-knot nematode (RKN) (Meloidogyne spp.) which is considered as one of the major limiting factors affecting tomato productions worldwide, especially in Egypt. Aim of study: The present study was performed to evaluate the quantitative and qualitative chitionolytic potentials of Serratia, Bacillus megaterium and B. subtilis as well as their nematicidal effect against Meloidogyne incognita under both in vitro and in vivo conditions. Methodology: Qualitative and quantitative assays of bacterial chitinase of the applied bacteria were determined using Chitinase assay agar and liquid media, as well as the nelson-somogyi method. Nematicidal and ovicidal activities of bacterial treatments were evaluated by Test Tube Bio-assay technique. A greenhouse experiment was conducted for in vivo evaluation of bacterial treatments on nematode parameters. The most effective bacterial isolate was molecular identified based on the nucleotide sequencing of its 16S rRNA gene. Results: Serratia sp. (S2) showed the highest total and specific chitinase activities (0.620 U/mL and 0.079 U/mg), respectively, followed by S1 (0.560 U/mL and 0.061 U/mg) and S3 (0.434 U/mL and 0.057 U/mg). B. megaterium appeared the minimum total and specific chitinase activities (0.320 U/mL and 0.042 U/mg), and no chitinase activities was shown for B. subtilis. Serratia sp. (S2) recorded the highest ovicidal activity (53.61%) even when applied at low concentration (1%). Among greenhouse experiment, Serratia sp. (S2) recorded the minimum number of galls and egg masses. The nucleotide sequence analysis of 16S rRNA gene of Serratia sp. (S2) proved that this isolate could be a strain related to S. marcescens, therefore, it was documented in GenBank as S. marcescens strain ARC3 under the accession number MN533708. Conclusion: The results indicated that S. marcescens strain ARC3 showed the maximum nematicidal potentiality against M. incognita and its significant chitinolytic activity play an essential role in such bio-control effect. Recommendation: Chitonlytic bacteria could be suggested as effective and eco-friendly alternative approach for controlling the M. incognita.

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Melᴏidᴏgyne species are the highest eradicative pest in most of yields causing huge lᴏsses in many crᴏps. The use ᴏf rhizᴏbacteria has gained attentiᴏn in the cᴏntrᴏl of Meloidogyne javanica. In ᴏur study, five rhizᴏbacteria were isᴏlated frᴏm sandy lᴏamy sᴏil samples in El Beheira gᴏvernᴏrate, and identified based ᴏn their mᴏlecular characteristics (16S rRNA sequences) and phylᴏgenetic analysis. The selected isᴏlates were Staphylᴏcᴏccus pasteuri, Pseudᴏmᴏnas japᴏnica, Bacillus cereus, B. altitudinis and B. safensis. The five bacterial strains exhibited satisfactᴏry nematicidal activity against M. javanica in vitro. Under field condition, the applied bacterial strains significantly increased the plant grᴏwth parameters and suppressed M. javanica reprᴏductive factᴏr but at different rates. Hᴏwever, P. japᴏnica shᴏwed the best results as significantly suppressed rᴏᴏt galling up tᴏ 63.73 tᴏ 82.08% during 2019 and 2020, respectively. As a result ᴏf the significant impact ᴏf the strain S. pasteuri DAM10, it cᴏuld be utilized as a biᴏcᴏntrᴏl factᴏr against rᴏᴏt-knᴏt diseases caused by M. javanica, and has nᴏt been previᴏusly repᴏrted yet. Therefᴏre, after further studies screened strains can be used as ᴏne ᴏf the biᴏlᴏgical cᴏntrᴏl agents that lead tᴏ imprᴏving plant grᴏwth and reducing nematᴏde infectiᴏn and thus reducing the use ᴏf chemical nematicides and helping tᴏ develᴏp safer sustainable agriculture.

Background: The COVID-19 pandemic has significantly affected global health systems and has influenced patterns of disease worldwide. Aim: The current study aims to analyze the patterns of toxicities before, during, and after the pandemic at Poison Control Center (PCC) Ain Shams University Hospitals, identifying any changes and their persistence after the pandemic. Methods: A retrospective observational study using PCC's database of patients admitted from January 1 st 2019 to December 31 st 2022. Results: Over four years, the center managed to service large number of patients peaking to 21,107 patients were hospitalized, in 2022. Most admissions were adults comprising 57.24% in 2019 to 62.14% in 2022. Females represented 54.77% of admissions in 2019 declining to 52.69% in 2020 and rising to 55.61% in 2022. Pharmaceutical poisoning accounted for 26.85% in 2019 and 27.13% in 2020 declining to 20.53% in 2022. Substance abuse, the second most common diagnosis in 2019 with 13.79% prevailed in 2022 with 21.38%. Improvement was the prevalent outcome with increase in demand leave and referral toward 2022. Gender and age significantly affected diagnoses and outcomes. Conclusion and Recommendations:This study concluded that the pandemic-related lockdowns and subsequent easing of restrictions resulted in behavioral, substance exposure and use changes. Some changes faded with the pandemic"s end, while others persisted and new behaviors became the norm. Urgent responses from healthcare providers and policymakers are needed, emphasizing mental health support and substance misuse initiatives, especially for vulnerable age groups.