山楂花腐病的研究Ⅰ.山楂花腐病的病原菌

 山楂花腐病是我国山楂生产上的一种新病害。病原菌在病僵果内越冬,翌年春季从地表潮湿处的病僵果上产生子囊盘。子囊盘肉质,灰褐色,盘径3~12毫米,盘柄长1~18毫米。子囊棍棒形,无色,子囊间有侧丝。子囊孢子椭园形或卵园形,单胞,无色,子囊孢子大小为7.4~16.1×4.9~7.4微米。分生孢子单胞,柠檬形,串生,孢子串可分枝,分生孢子大小为12.4~21.7×12.4~17.3微米。经观察及接种试验表明,除山楂外,接种的其他树种均不发病。根据形态特征及致病性山楂花腐病菌鉴定为Monilinia johnsonii(Ell.etEv.) Honey,在我国尚属首次发现。

STUDIES ON HAWTHORN BLOSSOM BLIGHT Ⅰ.CAUSAL ORGANISM

Recently hawthorn(Crataegus pinnatifida Bge.) blossom blight,a new disease in China,was prevalent in Anshan district of Liaoning province.
Apothecia of this causal fungus were found in spring as well as in the early and mid May in 1980 on mummified fruits of hawthorn embedded in the soil,debris or stones.Conidia were observed in mass on on the infected leaves on hawthorn trees.
Morphology of this causal fungus,either perfect stage or imperfect stage,was described.
Inoculation experiments showed that only ascospores infected young hawthorn leaves while conidia infected blossoms and in turn young developing fruits were infected.
On basis of morphological characteristics and specialization,the causal fungus was identified as Monilinia johnsonii(Ellis & Ev.) Honey.