蒜薹白斑腐烂的病原学研究

The Causal Agent of White Spot and Rot of Garlic Bolt

８０年代末期以来，陕西关中大蒜产区发生了一种原因不明的蒜薹病害，田间病株蒜圣上密生细小白色斑点，继而在贮藏中发生严重腐烂，造成重大经济损失。由病薹成功地分离和鉴定了病原菌。病原菌为膨胀匐柄霉Ｓｔｅｍｐｈｙｌｉ：“ｎｉｖｅｓｉｃａｒｉｚｉｍ（Ｗａｌｌｒｏｔｈ）Ｓｉｍｍｏｎｓ，回接引起相同的症状。该病原菌分生抱子梗直或略弯，淡褐色至褐色，长５６．７１Ｌｍ，宽５～８ｔＬｍ，梗端膨大成囊状，直径７～９Ｐｍ，具暗色带。分生抱子长方形、宽卵形，揽褐色，表面具细刺，具１～６个横隔膜，１～３个纵隔膜，在１～３个主要横隔膜处明显缢缩，尺度１９．２～５３．３Ｘ１３：１～２３．２μｍ，抱子长宽比为１：１．７。在培养中产生有性态Ｐ１ｅｏｓｐｏｒａｓｐ．。该菌还可引起严重的叶枯病。

An unknown bolt disease of garlic (Allium sativum ) occurred in garlic growingregions of middle Shaanxi since the late 80s'. Symptoms of the disease consisted of minute whitespot on bolt in commercial fields and severe rot in storages ,which caused serious losses of bolts.The causal agent was isolated and identified as Stemphylium vesicarium (Wallroth) Simmons,which caused the same symptom as in field by reinoculations. Conidiophores of the pathogen werestraight to variously curved, pale to mid brown , up to 56. 7μm long, 5～ 8 μm thick , vesicularswellings 7～9 μm` diam. with dark band. Conidia were oblong or broadly ovoid ,olive-brown ,ver-rucose with l～6 transverse and 1～3 longitudinal septa ,often constricted at the 3 major trans-verse septa , 19. 2～53. 3×13. 1～23. 2μm ,length/width ratio of l. 7. Pleospora teleomorphs pro-duced in culture. The pathogen also caused a severe leaf blight of garlic.