雷公藤角斑病病原鉴定及其生物学特性

Pathogenic identification and biological characteristics of the Tripterygium wilfordii angular leaf spot

对雷公藤角斑病病原进行分离鉴定及其生物学特性的研究。结果表明,该病病原菌为福木假尾孢。雷公藤角斑病病原菌菌丝在PDA上生长最好;菌丝生长最适pH值为5-6;最适温度为25℃;碳源中单糖、氮源中蛋白胨最有利于菌丝生长,菌丝对氮源的利用比对碳源的利用强。分生孢子在30℃下萌发速度较快,2 h后开始萌发,4 h后的萌发率达到98.6%;分生孢子可以从两端细胞、两端细胞及中间细胞萌发多个芽管,萌发pH值为6,且在相对湿度达到95%以上时,才有较高的萌发率,但对光照的反应不灵敏;其致死条件为温度50℃,时间10 min。

The pathogen of the Tripterygium wilfordii Hook. f. angular leaf spot was proved to be Pseudocercospora elaeodendri （ Agarwal ＆ Hasija） Deigghton. Hypha grew well in PDA. The most suitable pH was 5 -6 and the optimum temperature was 25 ~C. To the carbon and nitrogen nutrition, the monosaccharide was the most advantageous to the hypha＇s growth in the carbon nutrition, and the peptone was the most advantageous to the hypha＇s growth in the nitrogen nutrition. The hypha used the nitrogen nutrition more than the carbon nutrition. Conidia germinated rapidly at 30 ℃. They began to germinate after 2 hours, and the germination rate could reach 98.6% after 4 hours. The Conidia could germinate some buds from the 2 ends＇cells, 2 ends and intermediate cells. The optimum temperature for Conidia germination was 30 ℃. The optimum pH was 6. Conidia could reach a response high germination rate if the moisture was more than 95 percent. The Conidia responded insensitively to light and its lethal temperature was 50℃ for 10 min.