A screen house experiment was conducted to test the efficacy of leaf extract of mahogany (Khaya senegalensis L) for the control of root-knot nematodes of tomato. The completely randomized design was used to test the materials. Results obtained showed that the leaf extracts of the mahogany plant significantly (P˂0.05) reduced the population of the nematodes compared to the untreated seedlings. It also indicated that there is significant difference (P˂0.05) on the effect of the extract on the test organism between the varying concentrations of the extract used. The study revealed that the higher the concentration of the extract the more its effect on the test organism. The result also showed a significant variation (P˂0.05) in the extent of galling, plant height and root lenght in tomato treated with different levels of concentrations of the leaves extracts. The implications of these findings were discussed.

Background: Klebsiella pneumoniae is one of the crucial causes of nosocomial and community-acquired infections that can result in various infections in human. Objectives: The present study aim to investigate the prevalence of capsular serotypes, antimicrobial susceptibility and virulence characteristics of K. pneumoniae isolated from different Mansoura University Hospitals. Methodology: K. pneumoniae isolates were collected from different clinical sources at Mansoura University Hospitals. The antimicrobial susceptibility to 14 different antibiotics was determined by disk diffusion method. The capsular serotypes were assessed by quelling test. Serum resistance, haemagglutination, biofilm, lipase, protease and lecithinase enzymes production were assessed phenotypically. Moreover, four virulence genes (rmpA, fimH, kfuBC and wabG) were detected by PCR. The genetic relatedness among isolates was investigated using ERIC-PCR molecular typing. Results: Seventy-three isolates were confirmed as K. pneumoniae. The vast majority of isolates demonstrated MDR patterns (72.6%) including a high resistance rate to the beta-lactam antibiotics (ampicillin: 98.6%, amoxicillin-clavulanic acid: 97.26 %, piperacillin: 97.26 %, amoxicillin: 93.15% and cefotaxime: 94.52%). K1 and K2 were the main serotypes found among the isolates, K1 serotype was the predominant (79.45%). It was found that serum resistance was the highest detected virulence factor among isolates (95.9%) and lipase was the lowest detected factor (19.2%). Haemagglutination was detected in 63% of the isolates especially from rectal swab (83.3%) and sputum (72.7%). The biofilm formation was detected mainly among urine and blood isolates. rmpA, fimH, kfuBC and wabG genes were harbored by 20.5%, 92%, 66% and 94.5% of isolates, respectively. ERIC- PCR showed high genetic diversity (100%, typability, Simpson’s index of diversity= 1). Conclusion: The current study revealed the high antibiotic resistance levels, pathogenic potential, and genetic diversity among K. pneumoniae isolated from different clinical sources which is considered a serious health problem that necessitates interventions to control its spread.