In order to study the disease progress of Stylo anthrocnose and the inoculated plants reaction,the 6 weeks old of Stylosanthese guianensis cv.Reyan2 inoculated by the suspension liquid of Colletotrichum gloeos-porioides spores.Microscopic observations of the leaves revealed the infecting process and counting the disease index through plant symptoms.Spores germinated and a few spores formed appressorium at 4 h.Most of spores germinated at 6 h,and a large quantity of geminating spores formed appressorium at 12 h and began to form penetration pegs.The inoculated spores began to produce hyphae at 36 h,a lot of hyphae formed and staggered into a mesh on the surface of the leave at 48 h.The geminating spores began to form conidiophores at 60 h.Numerous of new spores began to produce at 72 h.Parts of inoculated spores have finished disease cycle in 72 h.In the same time,plants appeared disease symptom gradually:leaves color became yellow,the host cell membrane rupture at 24 h,brown necrosis appeared at 48 h,then dead line,sclerotinite,mycelium appeared on the leaves surface at 72 h.The host cell began to collapse at 96 h.Disease index is 54.52 at 8 days,55% of inoculated plants dead at 11 days.%为了研究胶孢炭疽菌在柱花草叶片上的侵染进程和植株接种病原菌后的反应，用胶孢炭疽菌孢子悬浮液接种生长6周的热研2号柱花草幼苗，显微观察接种后炭疽菌在柱花草叶片上的侵染过程，统计植株病情指数。结果表明，接种4 h 时孢子开始萌发、少量形成附着胞；6 h 孢子大量萌发，12 h 时大量附着胞形成并形成侵染钉；36 h时开始产生菌丝；48 h 时菌丝大量产生纠结成网状；60 h 时开始形成分生孢子梗；72 h 时产生新的分生孢子。接种72 h 部分病原菌完成了一个侵染循环。同时柱花草发病症状为：叶片24 h 黄化，有侵染点细胞膜破裂，48 h 出现褐色病斑，72 h 病斑出现黑褐色坏死线、点状菌核、绒毛状菌丝，96 h 细胞崩解死亡，组织液外流。8 d 病情指数为54．52，11 d 有55％的接种植株死亡。
展开▼
