First Report of Xanthomonas euvesicatoria Causing Bacterial Spot Disease in Tomato in Blue Nile State, Sudan

Abstract

Bacterial spot caused by Xanthomonas vesicatoria is considered to be a major constraint of tomato production all over the world in particular warmer and humid parts.A disease disorder was reported in autumn season 2015within the Blue Nile State in Sudanaffecting all aerial parts of tomato plant. Symptomatic tomato leaves were collected and sent toPlant Pathology Laboratory, Faculty of Agriculture, University of Khartoum. An investigation on whether a phytopathogen was associated with symptoms of bacterial spots damage on tomato was conducted.The pathogen wasisolated and characterized morphologically, biochemically and at molecular level. The bacterium wasidentified as Xanthomonaseuvesicatoria and confirmed by PCR and sequence analysis of the 16S RNA gene (GenBankAccession Nos MH047248, MH051263 and MG686236).The disease incidence was remarkably high in ALrosserisand Aldamazein which recorded 49.27 and 52.17%, respectively, while the disease severity was 28.28 and 30.32%, respectively. To our knowledge, this is the first report of Xanthomonaseuvesicatoria causing bacterial spot disease in tomato in Sudan.

Bacterial Spot of Tomato and Pepper in Africa: Diversity, Emergence of T5 Race, and Management

“…Based on routine pathogenicity and biochemical tests, the bacterial spot pathogens of tomato and pepper have been reported from a considerable number of countries in Africa and the associated Islands. Alongside South Africa, these countries include Egypt, Ethiopia, Ghana, Kenya, Malawi, Morocco, Mozambique, Niger, Nigeria, Reunion, Senegal, Seychelles, Sudan, Togo, Tunisia, Zambia, and Zimbabwe ( OEPP/EPPO, 1988 ; Okoli and Erinle, 1989 ; Bouzar et al, 1994a , b ; Black et al, 2001 ; Abd-Alla and Bashandy, 2008 ; Tawfik et al, 2009 ; Hamza et al, 2010 , 2012 ; Opara and Odibo, 2009 ; Jibrin et al, 2014 , 2015 ; Kebede et al, 2014 ; Lamini et al, 2015 ; Algam et al, 2018 ; Ashmawy et al, 2020 ). The specific species of the pathogen responsible for the disease are yet to be determined for a considerable number of countries.…”

“…In Ghana, a survey of tomato fields in Ashanti, Brong Ahafo, and Upper East regions identified X. vesicatoria as the causal organism of bacterial spot disease ( Lamini et al, 2015 ). In Sudan, X. euvesicatoria was reported from tomato and pepper in Blue Nile State and central Sudan ( Bouzar et al, 1994a ; Algam et al, 2018 ). X. perforans , X. vesicatoria , and X. gardneri are associated with bacterial spot of tomato in Ethiopia ( Kebede et al, 2014 ).…”