Espécies do complexo Fusarium fujikuroi causam podridão do colmo de milheto granífero no Brasil

Abstract

Grain millet is a plant adapted to arid regions due to its rusticity and used for animal and human consumption. In Brazil, the crop has its main use as cover in no tillage systems, but also to forage and grain production. Among the aspects that limit the production of this crop are fungi that cause diseases, including species of the genus Fusarium, which compromise crop yield and grain food safety through the production of mycotoxins. The primary literature on the millet – Fusarium association is scarce, although there has been a vast expansion of the culture in Brazil in recent times. In this study, it was investigated which species of the Fusarium fujikuroi FFSC complex can be found in association with grain millet stalks and which ones induce disease symptoms. From symptomatic and asymptomatic stalks, a collection of 18 isolates with morphological characteristics of Fusarium fujikuroi was obtained, from different producing regions in Brazil. Six different FFSC species were identified through molecular phylogenetic analysis of tef1 gene region sequences. All species caused stalk rot in millet when inoculated in young plants. Based on the knowledge obtained, it is possible to identify and monitor etiological agents, develop strategies to mitigate possible damage and contribute to phytosanitary management. It will also be possible to subsidize breeding programs to select resistant hybrids. The possibility that various grasses serve as a source of inoculum for pathogens of important crops, especially grasses, should be investigated.