Surveys of Fusaria associated with crown rot of wheat in eastern Australia

Abstract

Fusavium voseum 'Graminearum' was found to be the predominant fusarium associated with crown rot of wheat in the eastern wheat belt of Australia. This conclusion was based on quantitative surveys involving isolations from stem bases of crown rot-affected plants at growth stages 10.5-11 which were collected at random in the 1972, 1973 and 1974 growing seasons. The majority of the isolates of F. roseum 'Graminearum' did not form perithecia in culture or on sterile wheat straw and are referred to as group 1 isolates to distinguish them from group 2 isolates which normally form perithecia in culture. The two groups can also be distinguished on the basis of cultural characteristics. Several group 2 isolates were obtained from wheat stem bases. The results indicate that the incidence and severity of crown rot caused by F. roseum 'Graminearum' was greater in areas where plants were affected by low soil moisture. The disease was found to occur in all areas of the eastern wheat belt which were surveyed.