【作者】 兰建强；

【导师】 康振生；

【作者基本信息】 西北农林科技大学 ， 植物病理学， 2012， 博士

【摘要】 炭疽菌是一类地理分布广泛、寄主范围广泛的真菌，从单子叶植物到双子叶植物,从裸子植物到被子植物均有炭疽病害。炭疽菌在作物成熟前和成熟后都能侵染植株和果实，特别对成熟的热带作物危害极大，造成果实腐烂引起严重的经济损失并影响产品的出口质量，因此在植物病原真菌中占有较重要的地位。本文回顾了炭疽菌属Colletotrichum Corda的分类学研究历史，对炭疽菌属名称的演变进行了阐述，并对以Saccardo (1882-1921)为代表的传统分类系统，以及Arx (1957,1970)和Sutton(1980)提出的炭疽菌近代分类系统作了评价；同时芒果胶孢炭疽菌进行了生物学特性研究。获得的主要结果如下：1.以Arx和Sutton的现代分类系统为基础，坚持自然形态学为主，培养特征和寄主范围为辅，对本实验室保存的炭疽菌标本以及国内有关单位的标本400余份和作者近期所采标本70余份进行了研究，共鉴定出46个合格种及变种。其中：新种4个，分别为艾纳香盘长Gloeosporium blumeae，楠木生盘长孢Gloeosporium machilicola，西番莲生盘长孢Gloeosporium passigloricolum，葛藤炭疽菌Colletotrichum stephaniae；新组合和新种1个，扁平炭疽菌（Colletotrichum complanatum）；新纪录种12个，分别为山柑盘长孢Gloeosporium capparidis，树薯生炭疽菌Colletotrichum manihoticola，胡椒炭疽菌Colletotrichum piperis，悬钩子生炭疽菌Colletotrichum rubicola，点状黑盘孢Melanconium stictoides，可可盘长孢Gloeosporium theobromicolum，莛子藨柱盘孢Cylindrosporium triostei，矮小盘长孢Gloeosporium nanoti，秋海棠盘长孢Gloeosporiumbegoniae，落地生根盘长孢Gloeosporium bryophylli，樟盘长孢Gloeosporiumcinnamomi，地榆盘长孢Gloeosporium sanguisorbae；大陆新分布3个：蝴蝶兰炭疽菌Colletotrichum phalaenopsidis，蜀葵炭疽菌Colletotrichum althaeae，铁刀木盘长孢Gloeosporium cassiae～siameae。对这些种进行了描述，给予绘图及部分照片，并给出了这些种的检索表。2.对云南省6个地区13个芒果品种上分离的18个芒果炭疽菌株进行了致病性测定及对其培养性状进行了观察记录，筛选出了具有代表性的强致病性菌株；以强致病性菌株CG16接种三年芒，通过光学显微镜、扫描电子显微镜和透射电子显微镜对炭疽菌侵染芒果果实和叶片的过程、受炭疽菌侵染后寄主的组织病理学及施药后药剂对炭疽菌菌丝影响的超微结构进行了研究，采用分光光度计法测定了病菌侵入过程中受害果实的过氧化物酶（POD）、苯丙氨酸解氨酶（PAL）和多酚氧化酶（PPO）活性。研究结果表明，18个菌株的培养性状均存在明显差异，强致病菌株的菌丝颜色浅，稀薄，菌丝附着力强，在PDA培养基上产孢早，产孢量大；弱致病菌株的菌丝较致密，颜色多半较深，产孢晚，孢子量少。以强致病性菌株CG16接种芒果的过程表明，从接种芒果至出现症状需要1.5d左右。炭疽菌在侵染芒果的过程中，首先形成初期侵染菌丝（初生菌丝），随着初生菌丝的侵入和扩展，寄主细胞逐渐消解死亡，初生菌丝先在细胞间扩展，不断建立新的活体营养寄生关系。随着菌丝的侵入使寄主细胞最终坏死消解，后期在死亡的寄主细胞中扩展的菌丝逐渐变细、分枝增多（次生菌丝），次生菌丝在寄主体内大量繁殖扩展，分散或成菌丝束。在初生菌丝穿透寄主细胞壁的过程中形成一个漏斗状的菌丝锥，在与细胞壁接触的菌丝部位缢缩，常常形成1个隔膜,在穿过细胞壁后迅速膨大成正常菌丝。在病菌侵染的过程中，寄主组织和细胞发生了一系列病理变化，包括寄主细胞变形，细胞壁的变薄、畸形、部分消失，原生质体解体，叶绿体等细胞器的崩解、坏死，细胞死亡。药剂处理对炭疽菌菌丝的影响比较明显，施药后的菌丝细胞壁不规则加厚，细胞部分解体，细胞内大量物质外渗累积。在接近和接触菌丝的寄主细胞壁处，积累大量颜色较深的物质。在炭疽菌侵染芒果果实的过程中，接种果实的果皮中的POD、PPO、PAL活性均比健康果皮的高，说明炭疽菌的侵染过程中引起寄主的抗性反应与这三种物质有关。接种后随着接种天数的增加，酶活性也升高，接种CG16后三种酶活性的变化均比接种CG8后的变化明显，即致病力强的菌株诱导芒果果实内酶产生的能力比致病力弱的菌株强,产生的活性氧自由基也多，使寄主致病更快。CG16接种后第5d，POD的活性达到高峰，随后，随着寄主组织的崩解，抵抗病菌的能力下降，POD的活性也随之下降，PPO的活性变化趋势与POD基本一致。CG16接种后第3d开始，PAL活性达到最高值，随后显著下降。CG8接种后的酶活性变化与CG16比有一定的迟滞期，即接种后酶增长较缓慢，高峰期推迟，下降也较缓慢。更多还原

【Abstract】 Colletotrichum Corda had a widely geographical distribution and hosts. It caused seriousdiseases on different plants, especially for tropical crops. Therefore, it had very importantposition among phytopathogenic fungi. In this study, we retrospected research history of thetaxonomy of Colletotrichum Corda and expatiated on the evolvement of ColletotrichumCorda’s appellation, and also appraised traditional classifical system which represented bySaccardo (1882-1921) and neoteric classifical system that brought forward by Arx(1957,1970)&Sutton (1980), respectively. In addition, we also performed characterization ofbiology of Colletotrichum gloeosporioides (Penz.) Sacc. in Mango.1. Based on Von Arx&Sutton’s neoteric classifical system and the principle for naturialmorphology, and accompanied with host range, we studied more than400genusColletotrichum specimens that preserved in our lab and other related departments in Chinaincluding70genus collected recently. In total46species and form sp. are recognized andidentifed in this study. Among them, there are4new species: Gloeosporium blumeae，Gloeosporium machilicola， Gloeosporium passigloricolum， Colletotrichum stephaniae；one new species: Colletotrichum complanatum；12firstly discovered specie:Gloeosporium capparidis， Colletotrichum manihoticola， Colletotrichum piperis，Colletotrichum rubicola， Melanconium stictoides, Gloeosporium theobromicolum,Cylindrosporium triostei, Gloeosporium nanoti，Gloeosporium begoniae，Gloeosporiumbryophylli，Gloeosporium cinnamomi，Gloeosporium sanguisorbae；3mainland newlydistribution: Colletotrichum phalaenopsidis, Colletotrichum althaeae, Gloeosporium cassiaesiameae. A detail description for all species, drawings and some pictures were given in thetext. In addition, we offered a key of these species.2. Eighteen isolates of Colletotrichum gloeosporioides (Penz.) Sacc. were collected fromthirteen mango varieties of six places in Ynnan province. The cultivation character andpathogenetic comparisons of these isolates were observed and recorded. The representativestrong pathogenic strains were selected which offered materials for study of infection processand enzyme activity. Sannian mango were inoculated by strong pathogenic isolate. Theultrastructure of infection process of C. gloeosporioides on leaf and fruit, host pathology in infection process and fungi cell change after treatment of fungicide were observed by lightmicroscopy and election microscopy. In addition, the activity of peroxidase (POD),phenylalanine ammonialyase (PAL), and polyphenol oxidase (PPO) of mango fruit weredetected by spectrophotometer in infection process of C. gloeosporioides. The resultsindicated that the cultivation character of eighteen isolates of C. gloeosporioides is different.The pathogen with stronger pathogenicity has light color, thin and strong adhesive hyphae,and produced plentiful spores early. The pathogen with weaker pathogenicity has dense andheavy color hyphae, and produced few spores late. CG16was screened as strong pathogenicstrains. It needs one and half days from inoculation to symptom. After inoculation, primaryand secondary hyphae were found in infected tissue. Primary haphae extended between hostcells, host cells collapsed because of pathogen infecting. Second hyphae extended quickly andpropagated with dispersion or bundle. Hyphae first formed a funnel-shaped hyphal cone andproduced a septum near host cell wall in infection process, there was a striction near the hostcell wall, primary hyphae became swollen normal hyphae after penetrating host cell wall.During infection process, pathological change happened. The host cell wall became deformedand thin because of hyphal invasion, cellular protoplasm of host cells became disorganized,chloroplast in the infected host tissue disintegrated, chloroplast envelope was distorted anddisorganized partly. The effect of fungicide on pathogen is obvious. The fungi cell wallbecame thick, and organelle was disorganized, hyphae was dying. There was much hyphaeetravasation between hyphae and host after treatment.During the pathogen infecting process, the activities of POD, PPO and PAL in infectedmango pericarp were higher than health mango pericarp. It was indicated that POD, PPO, andPAL were involved in the occurrence of indeced resistance. Enzyme activities increased withinoculation days, the change of three kinds of enzymes activities inoculatecd by CG16ismore evident than that inoculated by CG8. It meant that the pathogen with strongerpothogenicity could induce mango fruit produced more enzyme than that less pathogenicity.Five days after inoculation by CG16, the POD activities were the highest, and then, resistanceability declined with disorganization of host cells, the change of POD activity fell, the changeof PPO activity was somewhat similar to POD. The activities of PAL were the highest threedays after Mango fruit inoculated by CG16, and then fell sharply. The change of enzymeactivities of mango inoculated by CG8was delayed compared with CG16, that is enzymeincreased slowly, peak hours pushed off, and fell off slowly after inoculation.更多还原