近年来,作为有希望的苹果品种北斗的栽培面积在迅速扩大,但霉心病的发生却成了大问题。因此,从1988、1989年开始定期采取北斗的果实,进行了萼筒开孔的有无与霉心果发生率关系的研究。结果发现北斗的萼筒开孔明了,每年均在7月以后,7月下旬最高,8月以后渐减少,认为霉心果的发生是从7月下旬开始的,以后渐增。7月上旬用注射针将本病原菌 Altemaria SP 和 Fusarium In recent years, as a promising apple variety Beidou cultivation area is rapidly expanding, but the occurrence of mildew has become a big problem. Therefore, from 1988 and 1989, the fruit of Beidou was regularly taken and the relationship between the presence of calyx tube open hole and the incidence of moldy fruit was studied. The results showed that dipper calyx tube open hole clear, every year after July, the highest in late July, gradually reduced after August, that the occurrence of mildew occurred from late July, and then increased. In early July with the needle will be the pathogen Altemaria SP and Fusarium