A new disease of maize in Bahia, Brazil, with special reference to its casual organism

Abstract

In the State of Bahia, Brazil, a new disease was observed in maize. The difficulty in classifying the causative organism is described in this paper.

Before this epidemic, the disease had apparently been reported only in the State of São Paulo. Field observations of the disease demonstrated its severity, as production was severely reduced. The virulence of the disease was later demonstrated in laboratory pathogenicity tests. Although the causal organism resembled the commonly named Diplodia macrospora Eale, certain morphological and cultural characteristics of the Bahiana race do not agree with the customary descriptions for Diplodia macrospora. There is apparently considerable confusion regarding Diplodia since no one has yet examined the type species of the fungus or applied modern criteria for its definition. The authors have left the Bahiana race unnamed until new information pertinent to the identification of Diplodia is published.