Surveys of Fusaria and other fungi associated with stalk rot of maize in Eastern Australia

Abstract

Fusarium roseum 'Graminearum' was the predominant fungus associated with stalk rot of maize in eastern Australia in the 1972, 1973 and 1974 growing seasons. All isolates of this pathogen were of the group 2 type. Other fungi isolated in order of frequency were Diplodia maydis, F. moniliforme 'Subglutinans', Bipolaris sorokiniana, Nigrospora oryzae, F. roseurn 'Semitectum', F. moniliforme, F. roseurn 'Equiscti', F. roseum 'Concolor', Macrophominaphaseolina, Rhizoctonia sp., F. roseum 'Acuminatum', F. oxysporum, F. solani, F. tricincturn and F. roseum 'Heterosporum'. The relative isolation frequencies of the fungi varied according to the seasonal conditions. Stalk rots were not of major importance in 1973, a relatively dry growing season. However, in 1974, a wet growing season, stalk rot diseases were common in all areas.