Severity of Colletotrichum falcatum and Fusarium moniliforme the causal agent of sugarcane red rot wilt disease in Suphanburi Province

Abstract

The epidemic of sugarcane red rot wilt disease causes the reduction of sugarcane yield (30-100% decreased) and sugar content yield (31-75% decreased) in sugarcane, this disease is crucial and should be monitored since sugarcane breeding program with testing disease interaction for the selection of new sugarcane varieties. Hence, the aim of this study was to evaluate the severity levels of Colletotrichum falcatum and Fusarium moniliforme, the causal agents of sugarcane red rot wilt disease in Suphanburi province for find out the most severe isolates. This research surveyed and collected red midrib symptoms in sugarcane leaves in U Thong District, Song Phi Nong District, and Sam Chuk District, with twelve samples. Pathogen isolated was conducted using tissue transplanting method. The disease severity was tested using the wound plug method on different sugarcane varieties including E-Hiao, DOA U Thong 8, DOA U Thong 10, LK92-11 and DOA Khon Kaen 3. Rating scores were done at 45 days after inoculation. The result showed that the severity level of C. falcatum was similar to F. moniliforme with symptom appearance in sugarcane stalk. The highest level of disease severity was observed in the Sam Chuk isolation as scores of 3.1 and 1.6, respectively followed by Song Phi Nong isolate and U Thong isolate. C. falcatum is more virulent than F. moniliforme. Moreover, disease interactions with five sugarcane varieties were different according to the resistance level of each sugarcane variety. Bout C. falcatum and F. moniliforme Sam Chuk isolates will be used to study preservation methods and to test disease reaction in the promising sugarcane clones for further certification of sugarcane varieties.