ARTIFICIAL INOCULATION TESTS FOR ASSESSING SCAB RESISTANCE OF WINTER WHEAT TO FUSARIUM GRAMINEARUM ScHWABE

摘要

Scab of wheat, also called Fusarium head blight, is caused mainly by Fusarium spp. and can result in considerable loss in grain yield. Scab usually occurs in areas where it is warm and humid during wheat anthesis. Scab disease has become frequent and widespread in Japan in recent years. For example, a severe outbreak with substantial yield loss took place in 1996 and 26.8 % of wheat production area in the whole country was damaged. In Hokkaido, things were even worse, over 40 % of wheat growing region was seriously hurt and yield reduced by 20 % at the same year. Because scab is becoming an increasing concern in Hokkaido's wheat production area, evaluation of winter wheat for resistance to scab is urgently required. Scab epidemics are largely influenced by such environmental factors as temperature and humidity during anthesis and because precipitation varies from year to year, natural epidemics occur irregularly and field evaluations of scab resistance in winter wheat are frequently not repeatable. Testing for scab resistance under controlled conditions is through the use of artificial inoculation. Many laboratory methods to test for resistance to scab have been developed (Buerstmayr et al 1996; Diamond and Cooke 1999). Of these, the cut-spike inoculation method (Takeda 1989) is a simple way to assay large amounts of plant materials simultaneously. The objective of this research is to evaluate scab resistance in winter wheat using this method.