人工接种对新月弯孢菌侵染玉米籽粒的影响

Effects of artificial inoculation methods on infection of the maize grains by Curvularia lunata

研究了人工接种不同接种时期和方法对新月弯孢菌侵染玉米籽粒的影响,结果表明:玉米弯孢叶斑病菌可以侵染玉米果穗籽粒,使玉米籽粒产生褐色病斑。伤口接种法能使玉米果穗100%发病;花丝通道接种也可导致果穗发病,但其发病频率很低;而花丝喷雾接种和苞叶喷雾接种病菌不能成功侵染玉米果穗籽粒;吐丝后10 d和乳熟期接种只能引起接种点籽粒发病,病菌扩展不好;但籽粒形成期接种的玉米果穗籽粒不仅接种点发病,而且其周围的籽粒也感染了病菌,病菌扩展情况较好。试验明确,玉米籽粒形成期采用伤口接种是使玉米籽粒发生弯孢叶斑病的一种较为理想的人工接种方法。

The influence of three inoculation periods and four inoculation methods on infection of the maize grains by Curvularia lunata were studied in this paper. The results indicated that C. lunata could infect the grains of maize and caused brown spots in the grains. Both wound inoculation and silk injection inoculation caused infection of maize grains but the incidence of infection by wound inoculation （100%） was higher than that by silk injection inoculation. However, the grains of maize could not be infected by either silk spraying inoculation or bract spraying inoculation. Among the three inoculation periods, the inoculations in 10 days after spin silking and during the milk stage caused the disease only in inoculated grains and the pathogens rarely spread. However, the inocolation during the grain-filling period caused the disease of the inoculated grains and their surrounding grains and the pathogens spread well. The above results showed that the best inoculation method was the wound inoculation during grain-filling period.