Comprehensive Investigation of Die-Back Disease Caused by Fusarium in Durian.
Ratiya PongpisuttaPisut KeawmaneeSunisa SanguansubParadorn DokchanSantiti BincaderVipaporn PhuntumartChainarong RattanakreetakulPublished in: Plants (Basel, Switzerland) (2023)
Durian ( Durio zibethinus L.) is an economically important crop in the southern and eastern parts of Thailand. The occurrence of die-back disease caused by plant pathogenic fungi poses a serious threat to the quality and quantity of durian products. However, the identification of causal agents has been a subject of mixed information and uncertainty. In this research, we conducted a comprehensive investigation of die-back disease in nine durian plantations located in Thailand. By analyzing a total of 86 Fusarium isolates obtained from infected tissues, we aimed to provide clarity and a better understanding of the fungal pathogens responsible for this economically significant disease. Through a combination of colony characteristics, microscopic morphology, and a multilocus sequence analysis (MLSA) of the internal transcribed spacer (ITS) region, translation elongation factor 1-α ( TEF1 - α ) gene, and RNA polymerase II gene ( RPB2 ) sequences, we were able to identify and categorize the isolates into three distinct groups, namely, Fusarium incarnatum , F. solani , and F. mangiferae. Koch's postulates demonstrated that only F. incarnatum and F. solani were capable of causing die-back symptoms. This research represents the first report of F. incarnatum as a causal agent of die-back disease in durian in Thailand. Additionally, this study uncovers the association of ambrosia beetles and F. solani , highlighting the potential involvement of E. similia in facilitating the spread of die-back disease caused by Fusarium in durian.