ムギ赤かび病菌子のう胞子,分生胞子の飛散消長および降雨との関係

Abstract

The ascospores and macroconidia dispersal of scab fungus was estimated by trapping on gelatin-coated slide glass in the fields of wheat from March 19 to May 29 in 1979. Ascospore dispersal began to increase from latter part of March, and macroconidia dispersal began generally from latter part of April. The spore dispersal was most abundant on a rainy day and the next day of rainy day whether it rained or not. The spore dispersal tends to increase in proportion to the amount of rainfall on a rainy day or on the first day of successive rainy days. But a little rainfall on the second or the third day of successive rainy days led to abundant spore dispersal. Moreover, there was a close correlation between time of rainfall and abundant spore dispersal. Rainfall between 9 a. m. and 9 p. m. led to abundant spore disperal, but rainfall between 9 p. m. and 9 a. m. of the next day had little effect on spore dispersal regardless of the amount of rainfall. The results indicated that the time of rainfall is the most critical factor determining spore dispersal.