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Different bacterial strains were recorded as onion rot pathogens. The candidate strains in one region may differ from the other and it may be only one pathogen responsible of the infection in an area or a combination from different pathogens. The present research aimed at detection of the main bacterial pathogen (s) causing onion rot in Egypt throughout storage. Five bacterial pathogens were detected with different occurrence percentage; Erwinia carotovora subspecies carotovora (48.14 %), Erwinia cacticida (18.51 %), Erwinia carotovora subspecies atroseptica (14.81 %), Burkholderia cepacia (14.81 %) and Pantoea sp. (3.7 %).

Objective: To investigate antimicrobial resistance mechanisms of isolated bacterial strains, and their correlation with virulence profile.Method: The cross-sectional study was conducted in January 2020 at outpatient health centres in Kafrelsheikh Governorate of Egypt, and comprised urine samples from patients regardless of age and gender. Midstream samples were collected into sterile swaps which were kept in ice-cooled boxes until transported to the laboratory within 5h. Antimicrobial resistance profile of the isolated Enterobacteriaceae was done using Kirby–Bauer disk diffusion method and was confirmed with Vitek compact 2. The phenotypic of carbapenemases and extended-spectrum beta lactamase was determined, and polymerase chain reaction was used, as appropriate. Data was analysed using SPSS 20.Results: Of the 199 patients, 101(50.7%) were females and 98(49.3%) were males. The majority 73(36.6%) were aged 30-50 years. Urinary tract infection was found in 68(34.2%) patients. In 28(41.2%) of these patients, there were 32 isolates of Enterobacterales; 21(65.62%) Klebsiella pneumoniae, 7(21.87%) Escherichia coli and 4(12.5%) Enterobacter cloacae. Of the 28(41.2%) patients, 24(85.7%) were infected with a single strain; 17(70.8%) Klebsiella pneumoniae, 4(16.7%) Escherichia coli and 3(12.5%) Enterobacter cloacae. In 3(10.7%) cases, there was co-infection with Escherichia coli and Klebsiella pneumoniae, and 1(3.6%) sample had mixed infection with Klebsiella pneumoniae and Enterobactercloacae. The other 40(58.8%) patients had other causative agents. Housewives, agricultural workers and those aged >50 years had a higher risk of urinary tract infections (p<0.05) Among Klebsiella pneumonia isolates, 6(28.5%) possessed carbapenemase-related genes and 4(19.1%) extended-spectrum beta lactamase-related genes. The carbapenemaserelated genes were bla-Verona integron-encoded metallo beta lactamase 6(100%) bla-New Delhi metallo beta lactamase-1 4(66.6%) and bla-oxacillinase-48 2(33.3%). The 4(19.1%) cases of extended-spectrum beta lactamaserelatedgenes had bla-temoneira gene 3(75%) and bla-sulfhydryl variable gene 4(100%). In Escherichia coli isolates, bla-oxacillinase-48 and bla-Cefotaximase genes were observed in 2(28.5%) cases. Virulence genes uridine diphosphateglucose 4-epimerase, fimbrial adhesion and mannose-resistance adhesin of Klebsiella spp genes in Klebsiella pneumoniae isolates were positive in in 16(76.2%), 14(66.7%) and 10(47.6%) cases, respectively. All 21(100%) isolates of Klebsiella pneumoniae were negative for mucoviscosity-associated gene A.Conclusion: There was evidence of the coexistence of bla- oxacillinase-48, bla-Verona integron-encoded metallo beta lactamase and bla-sulfhydryl variable genes in Klebsiella pneumoniae and Escherichia coli isolates from mixed urinary tract infection samples.Keywords: Carbapenemase, Klebsiella pneumoniae, Escherichia coli, Lactams

acterial soft rots, commonly caused by Erwinia carotovora subsp. carotovora or Erwinia chrysanthemi, and slippery skin, caused by Burkholderia gladioli subsp. allicola as well as sour skin, caused by Burkholderia cepacia of onion bulbs are among the most serious storage diseases of onion (Allium cepa L.) that lead to great loss in bulbs. In this study some biostimulants; chitosan, seaweed extract and humic acid were in vivo tested on onion plants, to determine their controlling potential against bacterial rot diseases. Application of biostimulants proved to be effective in reducing the bacterial rot in stored onion bulbs. All tested biostimulants increased photosynthetic pigments content in onion leaves and total phenols content in onion bulbs, meanwhile they declined lipid peroxidation and the electrolyte leakage percentage in onion bulbs. As a summary, chitosan, seaweed extract and humic acid could be applied to improve plant growth and stimulate plant defense against diseases in concern. These materials are cheap, available, easy to apply, hazardless and environmentally safe.

The olive (Olea europea L.) explants of Itrana cultivar were cultured on different types of medium i.e; Olive medium (OM), Woody Plant medium (WPM) and Murashige & Skoog medium (MS). Also, different explant types (shoot tips and nodal cuttings) were investigated. The results showed that the Olive medium (OM) with nodal cuttings proved to be the best medium and explant for establishment of olive plants cv. Itrana. The best multiplication for cv. Itrana was obtained with culturing on OM medium supplemented 3 mg l -1 zeatin. Shoot elongation was carried out on OM medium containing different concentrations of Gibberellic acid (GA 3 ). Adding 2 mg l -1 of GA 3 to the culture medium proved to be the best concentration for obtaining the highest shoots (10.66 cm). Shoot rooting was carried out on half strength OM medium with different types of auxins (IBA, NAA or IAA). IBA proved to be the most effective one for inducing rooting of shoots. Adding 3 mg l -1 of IBA achieved the highest number of roots (2.66) and root length (3.66 cm) and it was proved to be the best concentration for rooting stage. Adding 0.5 mgl -1 of Putrescine to the rooting medium proved to be the best concentration for root formation and growth. Finally hardening the produced plantlets were performed successfully in greenhouse in pots containing mixture of peat-moss, vermiculite and sand (1:1:1) V/V/V.