7 Publ. UEPG Ci. Biol. Saúde, Ponta Grossa, v.24, n.1, p.7-12, jan./jun. 2018 Disponível em <http://www.revistas2.uepg.br/index.php/biologica> DOI: 10.5212/Publ.Biologicas.v.24i1.0001 INDUCTION OF PHYTOALEXINS IN SORGHUM, SOYBEAN AND BEANS BY SUSPENSION OF ENDOPHYTIC FUNGI INDUÇÃO DE FITOALEXINAS EM SORGO, SOJA E FEIJÃO POR SUSPENSÃO DE FUNGOS ENDOFÍTICOS Elaine Pittner 1* , Janaina Marek 1 , Douglas Bortuli 1 Adriana Knob 1 , Leandro Alvarenga Santos 1 , Cacilda Márcia Duarte Rios Faria 1 1 State University of the Western Center, Guarapuava, Parana, Brazil * Corresponding Author: E-mail: elainepittner@hotmail.com - Phone number: +55 42 3629-8323 ABSTRACT O objetivo deste trabalho foi avaliar a capacidade de alguns fungos endofíticos em ativar ftoalexinas. Os fungos endofíticos foram isolados de plantas daninhas, na sequência foi realizado uma suspensão destes fungos e testados nos ensaios biológicos para verifcar a indução de ftoalexinas. Em sorgo os mesocótilos das plântulas foram acondicionados em tubos contendo os tratamentos e ao fnal foi realizado a leitura em 480 nm. Em cotilédones de soja e nos hipocótilos de feijão após aplicação dos tratamentos nestes, foram extraídas as ftoalexinas e realizado a leitura. Todos os tratamentos foram capazes de induzir o acúmulo de ftoalexina, porém os mais efcientes foram as suspensões dos fungos D10 (Aspergilus japonicus) D11 (Trichoderma tomentosum) e, Acibenzolar-s- metil (ASM) e ácido salicílico (AS). Palavras-chave: Acibenzolar-s-metil, ácido salicílico, plantas daninhas, biocida, metabólitos. ABSTRACT The objective of this work was to evaluate the ability of some endophytic fungi to activate phytoalexins. Endophytic fungi were isolated from weeds, followed by suspension of these fungi and tested in the biological assays to verify the phytoalexins induction. In sorghum the seedlings mesocotyls were packed in tubes containing the treatments and at the end reading was realized at 480 nm. In soybean cotyledons and bean hypocotyls after application of these treatments, phytoalexins were extracted and read. All treatments were able to induce the accumulation of phytoalexin, but the most effcient were suspensions of the fungi D10 (Aspergilus japonicus) D11 (Trichoderma tomentosum) and, Acibenzolar-s-metil (ASM) and salicylic acid (SA). Key words: Acibenzolar-s-methyl, salicylic acid, weeds, biocide, metabolites. INTRODUCTION The synthesis of phytoalexins occurs in cells adjacent to the site of infection through secondary metabolism, have low molecular mass and are mostly regulated by induction due to biotic and abiotic stress, and the molecular mechanisms underlying their cytotoxicity are largely unknown (AHUJA et al., 2012). Among the metabolites that are part of phytoalexins, there is a great chemical diversity, with more than three hundred types already characterized among different classes of chemical compounds, such as coumarins, diterpenes and favonoids, and are present in more than twenty families of superior plants (JEANDET et al., 2013). Phytoalexins are biocides, can be injurious to bacteria, fungi and nematodes. The mode of action on fungi includes cytoplasmic granulation,