Fusarium Head Blight in South Asia and South East Asia: Status and Future Prospects

摘要

Fusarium head blight (FHB) is a wheat disease of limited importance in South and South East Asia. Thus, resistance breeding against the disease in the region is very limited or negligible. However, studies on FHB—causing fungi, in particular G. zeae (an. F. graminearum) have received more attention in recent years. The risk of FHB occurrence in wheat is usually restricted to a few areas including mid-hills or the foothills of the Himalayas where rainfall at times coincides with the flowering stage. In South East Asia, the area grown to wheat is small and efforts to develop wheat as a commercial crop have been primarily hampered by the severity of foliar blight (C. sativus) followed by Fusarium spp. In recent years, the higher interest toward understanding and reducing the risk of FHB in South Asia likely resulted from an unusual epidemic in parts of Punjab in the early 90s, an apparently higher frequency of rains occurring after the flowering stage, and the increased global awareness of the effect of Fusarium toxins on grain quality and health aspects. Limited screening particularly of wheat materials targeted to the North Western regions is undertaken in India under greenhouse conditions but resistance is generally not satisfactory. This paper summarizes observations and studies published on Fusarium species that may cause FHB in wheat in South and South East Asia, and raises issues related to pathogen diversity in the Himalayan region where wheat is part of cropping systems with rice and maize, other G. zeae hosts. Current concerns are mainly related to plant pathology aspects including the need for better pathogen characterization.