Detecção de Xanthomonas spp. associadas a plantas daninhas em campos de produção de hortaliças no estado de Pernambuco

Detalhes bibliográficos
Ano de defesa: 2016
Autor(a) principal: SANTOS, Leandro Victor Silva dos lattes
Orientador(a): SOUZA, Elineide Barbosa de
Banca de defesa: SOUZA, Elineide Barbosa de, MESQUITA, Júlio Carlos Polimeni de, OLIVEIRA, Sônia Maria Alves de
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal Rural de Pernambuco
Programa de Pós-Graduação: Programa de Pós-Graduação em Fitopatologia
Departamento: Departamento de Agronomia
País: Brasil
Palavras-chave em Português:
Área do conhecimento CNPq:
Link de acesso: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/7844
Resumo: Species of plant pathogenic bacteria in Xanthomonas genus can infect a large host range and cause significant losses in commercial crops. Among these species are the bacterial complex which causes bacterial leaf spot in solanaceous (Xanthomonas vesicatoria, X. euvesicatoria, X. perforans and X. gardneri) and X. campestris pv. campestris, causal agent of brassica black rot. Due to its vast host range these bacteria can survive in weeds which grow between rows of alternative crops in the absence of the main crop. Therefore, this work had as objective to detect Xanthomonas species in weeds found in fields of vegetables in the state of Pernambuco, Northeastern region of Brazil. Bacterial colonies typical of the genus Xanthomonas were isolated from the weeds Aeollanthus suaveolens (CRM3), Amaranthus lividus (CRM11), A. lividus (CRM16), Althernanthera philoxerioides (CRM42), Sida glomerata (CRM53) and Emilia fosbergii (CRM60), growing naturally in solanaceous and brassica plantations. The phylogenetic analysis of the gyrB gene together with the PCR using specific primers allowed the identification of isolates as Xanthomonas euvesicatoria (CRM11, CRM16, CRM42, CRM53 and CRM 60) and X. campestris pv. campestris (CRM3). The isolates of X. euvesicatoria showed to be pathogenic to plants and fruits of tomato and pepper, being CRM42 and CRM53 able to induce soft rot in the fruits. The isolates CRM42, CRM53 and CRM60 degraded pectate in less than two days, which characterizes a strong pectinolitic activity. In addition, the five isolates of X. euvesicatoria also showed strong amylolytic activity. The isolate CRM3 of X. campestris pv. campestris was pathogenic for all species of brassica vegetables tested (cabbage, cauliflower, kale and broccoli). This study demonstrates the importance of weeds as alternative hosts and inoculum sources for X. euvesicatoria and X. campestris pv. campestris and is also the first report of these weeds as hosts of these Xanthomonas species.