Monilinia fructicola on loquat: An old pathogen invading a new host

Monilinia fructicola has been widely reported as the causal agent of brown rot disease on many Rosaceae family fruits worldwide. It has been reported on stone fruits, e.g., peach, plum, cherry, apricot and mume; as well as pome fruits, e.g., apple, pear and hawthorn. Loquat is a member of the Eriobotrya genus in subfamily Maloideae along with apple, pear and hawthorn. So far, loquat has not been reported as the host of any Monilia species. In June 2019, brown rot symptoms were observed on loquat fruits in an orchard in Wuhan, Hubei Province, China. Thirty single spore isolates were obtained and identified as M. fructicola based on morphological characteristics and molecular analysis. This is the first report of loquat brown rot disease caused by Monilia species in the world. Furthermore, upon artificial inoculation, all three Monilia species from peach in China, i.e., M. fructicola, M. mumecola and M. yunnanensis, could cause typical brown rot disease on loquat fruits. At the same time, M. fructicola isolates from loquat showed virulence similar to those isolates from peach when the pathogenicity test was conducted on peach fruits. These results suggested that loquat could be infected by other Monilia species and that isolates from loquat also have potential to damage other Rosaceae family fruits in practice.     

果实褐腐病的调查与防治研究

 通过系统考察,标本采集,分离培养、鉴定,电镜扫描及酯酶同工酶电泳分析,明确我国丛梗孢属Monilia的种类及其寄主与分布,通过室内毒力测定,筛选出有效化学药剂并对桃褐腐病进行两年的综合防治,防效明显.     

桃采后褐腐病生防酵母菌的筛选及鉴定

为筛选对由美澳型核果褐腐病菌(Monilinia fructicola)引起的桃褐腐病具有抑制作用的酵母菌株,采用平板对峙的试验方法,从新疆北部12个地区分离的102株酵母菌中筛选出7株对桃褐腐病菌具有显著抑制作用的酵母菌株,其中菌株EEQS-7D拮抗活性最强,该菌株对桃褐腐病菌的抑菌率达78.90%。人为打孔接种活体试验结果表明,该菌株可显著降低桃褐腐病发病程度,抑制率达51.83%。生防相关性状检测结果显示,该菌株能够产生蛋白酶,透明圈直径达到34.5 mm,说明EEQS-7D主要通过分泌蛋白酶达到抑制桃褐腐病的效果。通过对菌株EEQS-7D的形态特征观察、生理生化测试以及26S r DNA序列分析,鉴定该菌株为出芽短梗霉(Aureobasidium pullulans)。     

小檗碱与绿僵菌复配的相容性及对桃褐腐病菌的抑制作用

[目的]探讨小檗碱与绿僵菌复配的可能性。[方法]考察小檗碱对绿僵菌孢子萌发、菌丝生长及产孢的影响,并测定小檗碱与绿僵菌复配对桃褐腐病菌(Monilinia fructicola)的抑制作用。[结果]试验浓度的小檗碱对绿僵菌的孢子萌发、产孢量和菌落形成未产生明显影响;当绿僵菌与褐腐病菌共培养时,绿僵菌处于优势菌群,褐腐病菌未能影响绿僵菌的生长;小檗碱与绿僵菌复配能完全抑制褐腐病菌的生长。[结论]小檗碱和绿僵菌可混合使用,二者相容性好。     

利用葡萄籽油防治桃子采后褐腐病的研究

为探索桃采后褐腐病的新型非化学农药防治手段,研究了不同用量葡萄籽油处理(体积分数分别为0.5%、0.1%、0.05%、0.01%)对桃采后褐腐病的抑制效果。将褐腐病菌(Monilinia fruc-ticola)(终浓度:5×104 cfu/mL)和不同体积分数的葡萄籽油于PDB培养基中25℃下共培养24～96h,然后调查病原菌孢子萌发及芽管伸长情况。结果表明,当葡萄籽油体积分数≥0.05%时,其对病原菌孢子萌发的抑制率为100%。以打孔法人为模拟接种褐腐病菌(浓度:5×104 cfu/mL)至桃子上,随后接种不同体积分数的葡萄籽油,25℃下贮藏6d后调查褐腐病斑大小。结果表明,当葡萄籽油体积分数≥0.05%时,其在桃子体内对褐腐病斑的抑制率在50%以上,而且0.1%和0.5%的葡萄籽油用量对褐腐斑的抑制效果相当;当体积分数为0.01%时,葡萄籽油对病菌孢子萌发及桃褐腐斑的抑制效果大大降低。因此,将0.1%定为葡萄籽油抑制桃褐腐病菌的最佳用量。自然条件下,在1℃冷藏21d后,经0.1%葡萄籽油处理过的桃子发病率为20.0%,化学药剂戊唑醇处理过的桃子发病率为18.7%,而空白对照组发病率为45.5%,表明0.1%葡萄籽油的防治效果(56.0%)接近化学药剂防治效果(58.9%)。同时,对葡萄籽油处理过的果实进行了果实品质参数测定,包括果实硬度、可溶性固形物含量、维生素C含量、可滴定酸含量,结果表明,与空白对照组相比,葡萄籽油处理过的果实品质没有发生显著变化。说明葡萄籽油在防治桃采后褐腐病方面具有代替化学农药的潜力。     

桃褐腐病生防细菌的筛选及抑菌作用研究

从桃园土样中分离获得88个细菌菌株,采用对峙培养法筛选出8个对桃褐腐病菌有拮抗作用的菌株。其中菌株CE对桃褐腐病菌的营养生长明显抑制,抑菌带宽度为9 mm,并致使菌丝细胞畸形,膨大呈泡囊状,后期细胞破裂,细胞质外渗。桃离体接种试验表明,直接接种病原菌的桃第2天的发病率就达到100%,而接种拮抗菌CE 12 h后再接种病原菌的桃第3天才发病,第4天的发病率仅为56.5%。表明拮抗细菌CE不仅对桃褐腐病菌的营养生长有很强的抑制作用,而且能抑制病原菌的侵染,有延缓发病的作用,将为桃褐腐病的生物防治提供很好的生防材料。     

云南省葱蒜真菌病害2种新记录

在云南省储藏葱蒜鳞茎上新记录到两种病害 :由黑曲霉 ( Aspergillusniger V.Tiegh)引起的大蒜褐腐病和由葱腐葡萄孢 ( Botrytisallii Munn)引起的洋葱褐腐病。     

中国主要茶区茶树炭疽菌系统发育学

【目的】炭疽菌能够侵染茶树叶片并造成病叶干枯、脱落,论文旨在分离、鉴定中国主要茶区茶树炭疽病的病原菌,为茶树病害防治工作提供科学依据。【方法】利用单孢分离法对采自中国15省（市、自治区）茶区的茶树炭疽病病叶进行炭疽菌分离,并对其ITS、TUB2两个位点进行PCR扩增和测序,测序结果采用MEGA 6.0软件以邻接法（Neighbor-Joining,NJ）构建多基因位点系统发育树。对分离的菌株在马铃薯葡萄糖琼脂培养基（potato dextrose agar,PDA）上的形态特征进行描述。对龙井43和中茶108茶树品种叶片进行有伤和无伤处理后接种代表性菌株,测试其致病性。【结果】以茶树上分离的炭疽菌菌株的2个基因位点序列（ITS、TUB2）构建多基因位点系统发育树,Colletotrichum boninense CBS 123755作为外群,结果表明所有菌株聚为3支,其中45个菌株与C. camelliae聚为一族、28个与C. fructicola聚为一族、5个与C. siamense聚为一族,所有菌株均归属于C. gloeosporioides复合种,并且C. camelliae在中国茶区分布范围最广,为茶树炭疽菌的优势种。形态特征结果表明,C. camelliae在PDA培养基上生长速度平均11.8 mm·d^-1,菌落白色,气生菌丝致密,绒毛状,中央凸起,边缘整齐;菌核、刚毛未见;分生孢子梗、产孢细胞未见;分生孢子透明,光滑,圆柱状,两端钝圆或基部渐尖,（8-15）µm×（3-6）µm;菌丝附着胞褐色,棍棒状,不规则状,有分枝,（8-10.5）µm×（6.5-8）µm;分生孢子附着胞未见。C. fructicola在PDA培养基上生长速率平均6.76 mm·d^-1,菌落正面白色,背面中央褐色,边缘白色,气生菌丝致密,绒毛状;菌核、刚毛未见;分生孢子梗透明,有隔,具分枝,产孢细胞圆柱状,7-18 µm,顶端直径1-2 µm;分生孢子透明,圆柱状,两端钝圆,部分中部溢缩,（10-15）µm×（3-3.5）µm;菌丝附着胞深褐色,圆形,近圆形,不规则形,有分枝,（6.5-8）µm×（3.5-5.5）µm;分生孢子附着胞褐色或深褐色,圆形,（5-7）µm×（5-6.5）µm。C. siamense在PDA培养基上生长速率平均7.6 mm·d^-1,菌落白色,气生菌丝致密,绒毛状;菌核、刚毛未见;分生孢子梗透明,有隔,具分枝;产孢细胞圆柱状,8-16 µm,顶端直径1-2 µm;分生孢子透明,圆柱形,梭形,两端钝圆,部分中部有溢缩,（9.5-13.5）µm×（3-3.5）µm;菌丝附着胞深褐色,球形,棒状,不规则形,（5-8）µm×（3-5.5）µm。致病性测试结果表明,C. camelliae能侵染龙井43品种茶树有伤叶片,但对龙井43无伤叶片和中茶108有伤、无伤叶片无致病性,而C. fructicola和C. siamense 2个种对2个品种茶树有伤、无伤叶片均无致病性。【结论】基于系统发育学和形态学结合的方法对中国15省（市、自治区）部分茶区茶树病叶病原菌鉴定,基本明确C. camelliae为中国茶树炭疽菌优势种。     

鹿蹄草等中草药对油桃采后褐腐病抑制效果研究

在离体和活体条件下,测定鹿蹄草、厚朴等中草药单剂及鹿蹄草为主的各中草药复配组合对油桃采后褐腐病菌的抑制效果。结果表明:11号(鹿蹄草+厚朴+大黄),14号(鹿蹄草+高良姜+虎杖)复配组合在离体试验中抑菌效果最好,10 mg/mL浓度的抑制率分别达到89.77%,85.50%;两种组合的最小抑菌浓度(MIC)分别是1.25,2.5 mg/mL;最小杀菌浓度(MBC)分别是2.5,5.0 mg/mL。活体抑菌测定结果表明,11号和14号复配组合对油桃褐腐病菌有不同程度延缓侵染和抑制作用,但不能完全防治;0.05 mg/mL扑海因与11号组合20 mg/mL,0.10 mg/mL扑海因与11号组合10 mg/mL均能完全抑制褐腐病菌在油桃果实上的发生和蔓延。     

瑞香狼毒提取物对病原菌及桃酶的生物活性研究

用乙酸乙酯及其他溶剂,利用平行提取法提取瑞香狼毒活性物质,采用生长速率法对8种植物病原菌进行了抑菌活性测定;并且以大久保桃为试验对象,对不同浓度瑞香狼毒乙酸乙酯提取液控制桃褐腐病效果进行了研究;同时检测了桃3种抗病性酶活性。结果表明:瑞香狼毒乙酸乙酯提取物对8种供试植物病原菌中的7种有明显的抑制作用,其中完全抑制了桃褐腐病原菌、苹果腐烂病原菌、小麦赤霉病原菌、黄瓜枯萎病原菌生长;瑞香狼毒乙酸乙酯、水、甲醇、乙醇、石油醚提取物对桃褐腐病原菌均有抑制作用(抑菌率均高于60%),其中瑞香狼毒乙酸乙酯提取物完全抑制病原菌菌丝的生长;经3种浓度的乙酸乙酯提取物处理桃的病斑都小于对照,而质量浓度为20 mg/mL提取物控制桃腐烂效果最好。乙酸乙酯提取物显著地提高了桃PAL,POD活性,但诱导PPO活性不明显。     

福建猕猴桃病害调查与鉴定

本文报道福建１７种中华猕猴桃病害和１种毛花猕猴桃病害．其中真菌性病害１１种，细菌性病害、病毒病害、线虫病害各１种，生理性病害２种，病因未明的２种．中华猕猴桃灰纹病（ＣｌａｄｏｓｐｏｒｉｕｍｏｘｙｓｐｏｒｕｍＢｅｒｋ＆Ｃｕｒｔ．）和毛花猕猴桃圆灰斑病（Ｌｅｐｔｏｓｐｈａｅｒｉａｓｐ．）为国内首次报道．     

罗伦隐球酵母、褐腐病菌与甜樱桃果实在不同温度下的互作效应

 【目的】研究酵母拮抗菌Cryptococcus laurentii，病原菌Monilinia fructicola与甜樱桃果实在接种伤口处的互作效应。【方法】在‘先锋’甜樱桃果实伤口处分别单独接种病原菌、酵母拮抗菌以及病原菌与酵母拮抗菌共同接种，分析不同处理体系下果实的发病、酵母拮抗菌的生长动态、果实的脂质过氧化以及氧化酶与抗氧化酶活性的变化。【结果】酵母拮抗菌C. laurentii在25和1℃下均能有效抑制甜樱桃果实褐腐病M. fructicola发生。病原菌M. fructicola在接种初期刺激拮抗菌生长，而后期则抑制拮抗菌。单独接种病原菌M. fructicola或同时接种拮抗菌和病原菌均能诱导果实超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和过氧化物酶（POD）活性升高并加速脂质过氧化作用。病原菌M. fructicola侵染甜樱桃果实发病后特异诱导多酚氧化酶（PPO）同工酶新酶带出现；而拮抗菌C. laurentii对甜樱桃果实的抗氧化酶体系、脂质过氧化程度以及PPO同工酶谱的作用效果相对较弱。【结论】在酵母拮抗菌C. laurentii、病原菌M. fructicola与甜樱桃果实的相互作用中，甜樱桃果实褐腐病病害发生受到抑制的主要原因是M. fructicola刺激拮抗菌的生长并诱导果实抗性相关酶活性升高。     

外源水果储运期病害研究初报

对1999-2005年来自广州口岸的2000多批次入境水果进行了检验和病害鉴定，共鉴定出37种病害，其中3种系检疫性有害生物所致，分别为美澳型核果褐腐病菌（Moniliafructicola Poll）、可可毛色二孢（Lasiodiplodia theobromae （Pat.）Griff. ＆ Maubl.）和柑橘溃疡病菌（Xanthomonas axonopodis pv. citri），同时列出了各类水果储运期常见的病害种类．     

滇重楼2种真菌性叶斑病的初步研究

对栽培滇重楼病害进行调查、鉴定,明确滇重楼白霉病由半知菌类的柱隔孢(Ramularia)引起,褐斑病由细交链孢菌(Alter-naria tenuis Nees)引起,并针对这2种病害提出了建议性的生态防治措施。     

Carbendazim sensitivity in populations of Colletotrichum gloeosporioides complex infecting strawberry and yams in Hubei Province of China

The ascomycete fungus Colletotrichum gloeosporioides is a devastating plant pathogen with a wide host range and worldwide distribution. Carbendazim has been widely used to control anthracnose caused by the C. gloeosporioides complex in China for more than 30 years and resistance to carbendazim has been reported in China. A total of 125 Colletotrichum isolates of strawberry and yam were collected from different geographical regions in Hubei Province, China. Approximately 52.8% of Colletotrichum spp. isolates showed resistance to carbendazim. The isolates tested in this study belong to four species, and the frequencies of resistant isolates differed across Colletotrichum species. Resistant isolates were found in C. siamense and C. fructicola. In contrast, all isolates of C. gloeosporioides and C. aenigma were sensitive to carbendazim. Highly carbendazim-resistant isolates harbored the E198 A mutation in the β-tubulin 2(TUB2) gene, whereas moderately carbendazim-resistant isolates harbored the F200 Y mutation in the TUB2 gene. Carbendazim-sensitive Colletotrichum isolates in this study were not genetically similar enough to form a separate cluster from resistant isolates. The result of this study emphasizes the importance of knowing which Colletotrichum sp. is present, when strategies for disease control are made.     

红掌茎基腐病病原鉴定

 1996～1997年云南省热带作物科学研究所1～2年生地栽红掌发生了严重的茎基腐病,致使根、茎、叶柄变褐,叶片黄化,叶柄脱落,植株枯死。从病组织和土壤基质中分别分离到40和33个分离物,经鉴定寄生疫霉Phytophthora parasitica,光孢镰刀菌Fusariumoxyspo-rum为红掌茎基腐的致病菌。     

Interaction Between Cryptococcus laurentii, Monilinia fructicola, and Sweet Cherry Fruit at Different Temperatures

The present study was performed mainly to investigate the antagonist-pathogen-host interaction in wounds of the sweet cherry fruits. The antagonistic yeast Cryptococcus laurentii could significantly reduce the brown rot of the sweet cherry fruit caused by Monilinia fructicola at 25 and 1 ℃. The populations of yeast increased faster in the presence of the pathogen initially, but then decreased rapidly. In the fruits inoculated with M. fructicola alone or combined with C. laurentii, an induction of lipid peroxidation as well as activities of the antioxidant enzymes, such as, superoxide dismutases （SOD）, catalase （CAT）, and peroxidase （POD）, was observed. The isoenzyme pattern of polypheno/oxidase （PPO） changed greatly after the symptoms appeared, with new PPO isoforms being induced. By contrast, the induction of lipid peroxidation and activities of SOD, CAT, and POD were low, although no significant changes were found in the PPO isoenzyms in the fruits inoculated with antagonist C. laurentii alone. The inhibition of brown rot during the antagonist- pathogen-host interaction in wounds of the sweet cherry fruits was mainly on account of the stimulated growth of C. laurentii as well as the induction of antioxidant enzymes of the fruits by M. fructicola.     

香蕉细菌性软腐病菌的寄主范围及香蕉品种的抗性测定

以分离获得的3个香蕉细菌性软腐病菌为接种菌株,采用针刺和注射等接种方法进行了香蕉细菌性软腐病菌寄主范围的鉴定,并对香蕉不同品种的抗性进行了测定.结果表明,在供试的15科22种植物中有21种植物可以被病原菌侵染而发病,表明该病原菌寄主范围广泛.对我国普遍栽种的7个香蕉品种的抗性测定结果表明,不同香蕉品种抗性存在差异,其中皇帝蕉为高抗品种;农科1号、大蕉和巴西蕉为中抗品种;而金粉、广粉和威廉斯B6为中感品种.     

三七根腐病病原研究

【目的】三七根腐病是三七的重要病害，是限制三七种植业发展的严重障碍。【方法】在田间进行系统的三七根腐病害观察、调查和采样；在室内进行病原分离、鉴定和室内致病性测定，并进行田间人工接种试验。【结果】发现三七根腐病的主要症状表现有黄腐型、干裂型、髓烂型、急性青枯型、湿腐型和茎基干枯型等，但以黄腐型和急性青枯型较为常见，其中干裂型、髓烂型和茎基干枯型是新发现的三七根腐病症状表现。分离和鉴定结果表明，引起三七根腐病的病原真菌类群主要包括Cylindrocarpon destructans、C. didynum、Fusarium solani、F. oxysporum、Phytophthora cactorum、Phoma herbarum、Rhizoctonia solani等。室内致病性测定结果表明C. didynum、C. destructans、P. cactorum、P. herbarum和R. solani均能导致块根不同程度的腐烂。田间人工接种以P. cactorum和P. herbarum的致病性较强，发病率分别为48.4%和50.0%。C. destructans和C. didynum的致病力虽然较弱（C. destructans为23.5%，两株C. didynum分别为28.0%和15.2%），但在田间分布范围广，分离频率高（Cylindrocarpon属真菌最高组织分离频率为100%），且可导致典型的黄腐型症状。【结论】C. destructans和C. didynum是田间三七根腐病的重要病原真菌。     

猕猴桃采后腐烂病原的鉴定

2015年9月,于湖南省浏阳果园内发现大量采摘后易腐烂的猕猴桃,腐烂部位有明显块状褐色病斑。对染病猕猴桃腐烂部位进行病原物的分离纯化、形态学观察和致病力验证、分子生物学方法进一步区分鉴定病原菌,结果表明,导致猕猴桃腐烂的病原菌为大豆拟茎点种腐病菌(Phomopsis longicolla)。