Effect of chemical and biological seed treatments on common bean seeds inoculated with Fusarium oxysporum f. sp. phaseoli

• Published in: Arquivos do Instituto Biológico (São Paulo) Vol. 87; p. 1
• Main Authors: Ishizuka, Mariane Sayuri, Castro, Renata Rebellato Linhares de, Moraes, Maria Heloisa Duarte de, Menten, José Otavio Machado
• Format: Journal Article
• Language: English; Portuguese
• Published: Sao Paulo Instituto Biologico 2020
• Subjects: Beans; Biological effects; Biological products; Dry matter; Emergence; Flutriafol; Fungi; Fungicides; Fusarium; Fusarium oxysporum; Germination; Infestation; Pathogens; Pesticides; Phaseolus vulgaris; Physiological effects; Seed treatments; Seedlings; Seeds; Substrates; Trichoderma; Wilt
• ISSN: 0020-3653; 1808-1657
• DOI: 10.1590/1808-1657000702018

Currently, the common bean (Phaseolus vulgaris L.) productivity has been reduced by the fungus Fusarium oxysporum f. sp. phaseoli (Fop), the causative agent of Fusarium wilt. Considering the integrated management of diseases, the objectives of the present work were to verify the compatibility between chemical and biological fungicides for Fusarium oxysporum Schlecht. f. sp. phaseoli Kendrick & Snyder (Fop) control in common bean seeds. In laboratory, the effects of the treatments were evaluated by sanity, germination, seedling total length and seedling dry matter tests. In greenhouse conditions, the emergence speed rate, the percentage of emergence and the rate of pathogen transmission through the pathogen infestation in a substrate to plants were evaluated. Common bean seeds BRS Estilo were artificially inoculated with Fop isolate (IAC 11.299-1). In the seeds’ treatment, the chemical fungicides fludyoxonyl, flutriafol, methyl tiofanate, and biological products of Trichoderma sp. (isolates SF04, GF 422 and strain 1306), separately and mixed, were used. Treatments that promoted the best pathogen control in seeds were the combination of methyl tiophanate with biological products. Both flutriafol and GF 422 isolated and in mixed treatments affected the seeds’ physiological quality. The protective effect of the products was noted in the transmission test, whose Fop incidence was from 5 to 40% in the hypocotyl and from 5 to 30% in common bean roots.
RESUMO: Atualmente, a produtividade do feijão comum (Phaseolus vulgaris L.) foi reduzida pelo fungo Fusarium oxysporum f. sp. phaseoli (Fop), o agente causador da murcha de Fusarium. Considerando o manejo integrado de doenças, os objetivos do presente trabalho foram verificar a compatibilidade entre fungicidas químicos e biológicos para Fusarium oxysporum Schlecht. f. sp. phaseoli Kendrick & Snyder (Fop) em sementes de feijão. Em laboratório, foram avaliados os efeitos dos tratamentos pelos testes de sanidade, germinação, comprimento total de plântulas e matéria seca de plântulas. Em uma estufa, foram avaliadas a velocidade de emergência, a porcentagem de emergência e a taxa de transmissão de patógenos através da infestação de patógenos no substrato às plantas. As sementes de feijão comum BRS Estilo foram inoculadas artificialmente com isolado Fop (IAC 11.299-1). No tratamento das sementes, foram utilizados os fungicidas químicos fludioxoxil, flutriafol, tiofanato metílico e produtos biológicos de Trichoderma sp. (isolados SF04, GF 422 e cepa 1306), separadamente e misturados. Os tratamentos que promoveram o melhor controle de patógenos nas sementes foram a combinação de tiofanato de metila com produtos biológicos. Tanto o flutriafol quanto o GF 422 isolados e em tratamentos com misturas afetaram a qualidade fisiológica das sementes. O efeito protetor dos produtos foi observado no teste de transmissão, cuja incidência de Fop foi de 5 a 40% no hipocótilo e de 5 a 30% nas raízes do feijão comum.