New report of additional Enterobacterial species causing Wilt in West Bengal, India.

Ralstonia solanacearum, is known to be the most prominent causal agent of bacterial wilt worldwide. It has a wide host range comprising of solanaceous and non-solanaceous plants. Typical symptoms of the disease are leaf wilt, browning of vascular tissues and collapsing of the plant. With the objective of studying the diversity of bacterial wilt causing pathogen in West Bengal, samples of diseased symptomatic crops and adjacent symptomatic and asymptomatic weeds from widespread locations in West Bengal were collected. A majority of these strains (68 out of 71) were not found to be R.solanacearum through routine molecular identification test specific to ‘R. solanacearum species complex’. A presumptive identification of these isolates with conventional biochemicals, an extensive testing of pathogenicity of a subset involving greenhouse trials fulfilling Koch’s Postulate test and SEM analysis for presence of the pathogen in diseased plants were done. 16s rDNA sequencing of a subset of these strains (Genbank- Accession No. JX880249-JX880251) and analysis of sequences with nBLAST programme showed a high similarity (97-99%) to the sequences of Enterobacteriaceae group available in the Genbank. Molecular phylogeny further established the taxonomic position of the strains. The three bacterial strain cultures have been submitted to MTCC, Institute of Microbial Technology, Chandigarh, India and identified as Klebsiella oxytoca, Enterobacter cowanii and Klebsiella oxytoca respectively. Although Enterobacter sp. has previously been reported causing wilt in many plants, susceptibility of most of the dedicated hosts of R.solanacearum to wilt caused by Enterobacter and other bacteria from Enterobacteriaceae is being reported for the first time in this work.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author