侵染山楂的梨胶锈山楂专化型的鉴定及生物学特性研究

IDENTIFICATION AND BIOLOGICAL CHARACTERISTICS OF GYMNOSPORANGIUM ASIATICUM MIYABE EX YAMADA F.SP.CRATAEGICOLA INFECTING HAWTHORN

根据山楂锈病菌的形态特征及致病性,初步鉴定为梨胶锈山楂专化型(Gymnosporan-gium asiaticum Miyabe ex Yamada f.sp.crataegicola)。冬孢子角吸水胶化后1小时萌发产生担孢子,24小时达到最高萌发率。冬孢子萌发的温度范围为5℃～25℃,适宜温度10℃～35℃;担孢子萌发的温度范围为5℃～25℃,适宜温度15℃～25℃。两种孢子在有水膜的情况下才能萌发,不需要补充营养。冬孢子角在室温下能存活60天左右,5℃冰箱中可存活4个月左右。单个的冬孢子及担孢子不耐干燥,1～2天便全部死亡。

Hawthorn rust fungus was preliminarily identified as Gymnosporangium asi-aticum Miyabe ex Yamada f.sp.crataegicola,on the basis of the morphologicalcharacters and pathogenicity.The horn-like telia from the rust germinated and formed basidiospores when telia absorbed water and gelatinized for 1 hour,and reached the highest germination percentage 24 hours later.Teliosporescould germinate over a temperature range of 5～35℃, and the optimumtemperature for germination is at 10～25℃;basidiospores could germinate at5～25℃,however,the optimum temperature for their germination is at 15～25℃.The two kinds of spores only germinated in a film of water,withoutany supplements of nutrients are required.The horn-like telia could surviveabout 60 days in room temperature,and about 4 months at 5℃ in refrigerator.Single teliospore or basidiospore has no resistance to dry condition inwhich the single spore died completely within 1～2 days.