Stem rot caused by Sclerotinia sclerotiorum is a major fungal disease of canola worldwide. In Australia the management of stem rot relies primarily on strategic application of synthetic fungicides. In an attempt to find alternative strategies for the management of the disease, 514 naturally occurring bacterial isolates were screened for antagonism to S. sclerotiorum. Antifungal activity against mycelial growth of the fungus was exhibited by three isolates of bacteria. The bacteria were identified as Bacillus cereus (SC-1 and P-1) and Bacillus subtilis (W-67) via 16S rRNA sequencing. In vitro antagonism assays using these isolates resulted in significant inhibition of mycelial elongation and complete inhibition of sclerotial germination by both non-volatile and volatile metabolites. The antagonistic strains caused a significant reduction in the viability of sclerotia when tested in a greenhouse pot trial with soil collected from the field. Spray treatments of bacterial strains reduced disease incidence and yielded higher control efficacy both on inoculated cotyledons and stems. Application of SC-1 and W-67 in the field at 10% flowering stage (growth stage 4Á00) of canola demonstrated that control efficacy of SC-1 was significantly higher in all three trials (over 2 years) when sprayed twice at 7-day intervals. The greatest control of disease was observed with the fungicide Prosaro â 420SC or with two applications of SC-1. The results demonstrated that, in the light of environmental concerns and increasing cost of fungicides, B. cereus SC-1 may have potential as a biological control agent of sclerotinia stem rot of canola in Australia.

The aim of the present study was to detect the pathogenic Escherichia coli (E. coli) through pathological study of the colibacillosis affected birds. These isolated E. coli were further confirmed by PCR using specific primer. For this purpose, a total of 20 swabs (10 from lung and 10 from intestine of 10 dead birds) were collected in sterile nutrient broth. The histopathological samples were collected in 10% buffered neutral formalin. The used methods were histopathology, isolation and identification of E. coli by conventional methods and as well as by PCR method. A total of 10 isolates of E. coli from 20 swabs of lung and intestine was characterized by conventional routine methods of bacteriology. Gross pathological lesions of all lungs in the present investigation were congested and consolidated. Duodenum showed congestion and hemorrhages with excess mucus in the luminal surface of it. Microscopically, all the lungs showed severe congestion, infiltration of heterophils, macrophages and lymphocytes in the wall of bronchus as well as in the peribronchial alveoli. E. coli infected all the duodenum showed severe infiltration of leukocytes mainly heterophils, lymphocytes and macrophages in the submucosa of the duodenal wall. In this study, DNA of 8 isolates out of 10 isolated E. coli organisms was amplified by PCR using ECO-f and ECO-r primer targeting 16S ribosomal DNA and found 585 bp amplicon which is specific for E. coli with enteroinvasive type confirmed by histopathological lesions in duodenum. Further investigation should be focused on serotyping and detection of genes of E. coli which are responsible for pathogenicity of the organism.DOI = http://dx.doi.org/10.3329/bjvm.v9i1.11205Bangl. J. Vet. Med. (2011). 9(1): 17-25

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Bangladesh receives most of its precipitation from June to September in the form of rainfall as a part of the Asian summer monsoon system. Bangladesh is a relatively flat region, surrounded by the southern Himalayas and Meghalaya Plateau in the north, Arakan Mountains in the east, and the Bay of Bengal (BOB) in the south. Although several studies have investigated the mechanisms that drive the Asian monsoon precipitation, very few studies have focused on the monsoon precipitation in Bangladesh. This study investigated the influence of the topography of the surrounding regions and sea surface temperature on the summer monsoon precipitation of Bangladesh and the surrounding regions. Using observed data, we showed that moisture convergence near the mountains contributes to the precipitation of Bangladesh, whereas the BOB acts as a source of moisture. A strong low-level jet carries the moisture inland as the land-sea thermal contrast intensifies the wind circulation during the summer. Three differently forced simulations of the Euro-Mediterranean Centre on Climate Change coupled climate model (CMCC CM2) were analysed to investigate the influence of the surrounding region's topography and sea surface temperature on the summer monsoon precipitation. The low-resolution simulation showed no spatial variability of precipitation and dry bias due to the overly smooth topographical representation of mountains. The high-resolution coupled simulation, with a better representation of topography, improved the moisture convergence at the foothills and precipitation bias. The high-resolution prescribed sea surface temperature further improved the precipitation bias by intensifying the lowlevel jet that transports moisture over Bangladesh.