云南弥勒甘蔗褐条病病原菌的分离鉴定

2019年10月,在云南弥勒甘蔗示范基地(23.92°N,103.33°E)发现‘云瑞10-187’和‘福农11-2907’高感甘蔗褐条病,发病率为50%～80%。为明确其病原,本研究采集病样进行了病原菌的分离、鉴定及系统发育分析,以期为该病害有效防控提供科学依据。依据形态特征、核糖体RNA的内转录间隔区(internal transcribed spacer, ITS)和甘油醛-3-磷酸脱氢酶基因(glyceraldehyde-3-phosphate dehydrogenase, GAPDH)分子鉴定及致病性测定,将病原菌鉴定为狗尾草平脐蠕孢Bipolaris setariae,是云南省甘蔗褐条病病原菌新记录种,丰富了甘蔗褐条病病原菌信息,为后续其他蔗区褐条病的研究奠定了基础。     

甘蔗褐锈病研究进展

由黑头柄锈菌(Puccinia melanocephala)引起的甘蔗褐锈病在世界甘蔗种植区广泛分布,也是我国蔗区发生最普遍、为害最严重的叶部病害。本文从甘蔗褐锈病的分布与为害、病原菌特征与生物学特性、病菌侵染过程、病害发生规律、寄主抗病性以及防治等方面进行了综述,旨在为病害的有效防控提供依据。     

黄帚橐吾提取物对棉铃虫的生物活性

为掌握贵州甘蔗真菌病害种类及发生情况,采用随机踏查、定点调查、症状诊断与病原菌形态特征观察等方法对贵州甘蔗产区7个县进行真菌病害调查;采用菌丝生长速率法,对甘蔗褐斑病进行了5种杀菌剂室内毒力测定和田间防效试验。结果表明,贵州甘蔗主要真菌病害有褐斑病、褐锈病、赤腐病、黄斑病、轮斑病、褐条病、煤烟病、黑穗病,其中褐斑病、轮斑病、褐条病发生较重,煤烟病发生严重;5种杀菌剂中,325 g/L苯甲· 嘧菌酯悬浮剂对甘蔗褐斑病毒力最高和防效最好,EC50为0.0025 mg/L,第3次药后10 d防效达86.46%。其他4种杀菌剂对褐斑病均有较好的防治效果,可应用于甘蔗生产防治褐斑病。     

怎样防治旱地蔗病虫害

怎样防治旱地蔗病虫害罗林钟卞光文（重庆市合川科学技术协会４０１５２０重庆市合川三江（涪江、渠江、嘉陵江）旱地蔗区虫害以蔗螟和蔗龟较多。蔗螟以二点螟为主，还有条螟、白螟、大螟。蔗龟主要是二点褐金龟发生较严重；甘蔗的病害则以黑穗病和叶斑病发生较多。现将其...     

贵州甘蔗真菌病害初步调查及褐斑病防治药剂筛选

为掌握贵州甘蔗真菌病害种类及发生情况,采用随机踏查、定点调查、症状诊断与病原菌形态特征观察等方法对贵州甘蔗产区7个县进行真菌病害调查;采用菌丝生长速率法,对甘蔗褐斑病进行了5种杀菌剂室内毒力测定和田间防效试验。结果表明,贵州甘蔗主要真菌病害有褐斑病、褐锈病、赤腐病、黄斑病、轮斑病、褐条病、煤烟病、黑穗病,其中褐斑病、轮斑病、褐条病发生较重,煤烟病发生严重;5种杀菌剂中,325g/L苯甲·嘧菌酯悬浮剂对甘蔗褐斑病毒力最高,防效最好,EC50为0.002 5mg/L,第3次药后10d防效达86.46%。其他4种杀菌剂对褐斑病均有较好的防治效果,可应用于甘蔗生产防治褐斑病。     

云南甘蔗白条病的多基因联合鉴定

甘蔗白条病是由白条黄单胞菌Xanthomonas albilineans(Ashby) Dowson引起的甘蔗重要病害。2017年在云南保山、孟定和金平蔗区的甘蔗上发现疑似白条病的病害。从病株蔗茎中分离得到圆形,凸面,光滑,有光泽,黄色的细菌菌落。经柯赫氏法则验证,分离得到的细菌为该病害的病原菌。使用16S rRNA基因、gyrB基因和rpoD基因对分离得到的病原菌进行了分子鉴定,BLAST和系统发育分析表明本研究所获得的病原菌的3个基因的核苷酸序列与白条黄单胞菌GPE PC73菌株(GenBank登录号:FP565176)对应基因的核苷酸序列一致性均为100%,在系统发育树中处于同一分支。根据田间症状诊断、柯赫氏法则验证及分子鉴定结果,确认云南保山、孟定和金平发生的甘蔗病害为X.albilineans引起的甘蔗白条病。     

甘蔗优良新品种(系)抗褐锈病基因Bru1的分子检测及自然抗性评价

甘蔗褐锈病是目前中国蔗区发生最普遍、危害最严重的病害之一,选育和种植抗病品种是防治该病最为经济有效的措施。为明确近年国家甘蔗体系育成的50个新品种(系)对甘蔗褐锈病的抗性,确定其应用潜力,本研究通过在甘蔗褐锈病高发蔗区云南德宏、保山2个区域化试验站,采用田间自然抗性调查与分子标记辅助鉴定抗性基因的方法,于2014年和2015年对中国近年选育的50个优良新品种(系)及2个主栽品种进行抗褐锈病基因Bru1的分子检测及自然抗性评价。田间自然发病调查结果表明,50个优良新品种(系)及2个主栽品种中,高抗至中抗的有34个,占65.38%。其中15个材料表现高抗,占28.85%,16个材料表现抗病,占30.77%,3个材料表现中抗,占5.77%;分子检测结果显示,共29个抗病材料含有抗褐锈病基因Bru1,出现频率为55.77%,表明中国近年选育的优良新品种(系)中抗褐锈病性主要由Bru1控制;其余5个抗病材料均不含抗褐锈病基因Bru1,暗示除了Bru1外,可能还有其他抗褐锈病基因存在。不同系列品种田间感病品种的频率和含抗褐锈病基因Bru1的频率不同,粤糖系列品种感病品种的频率最高达到60%,含Bru1的频率最低,只有30%,抗性最弱;云蔗系列品种感锈病品种的频率最低只有12.5%,含Bru1的频率最高,达到81.25%,抗性最好。本研究结果为深入开展甘蔗抗褐锈病育种,选育和推广优良抗病品种,有效防控甘蔗褐锈病提供了科学依据和优良抗性新品种(系)。     

勐甘蔗区甘蔗褐条病重发原因分析与防治措施

甘蔗褐条病是沧源县勐甘蔗区甘蔗上近年发展起来的主要病害。5～9月是该病的流行期,发生主要受种苗带菌、品种抗病性、气候条件、栽培水平等因素影响。针对发病因素,提出和实施了有效的综合防治措施。     

甘蔗抗感黑穗病池的构建和抗病基因分子标记

 由甘蔗黑穗病菌(Ustilago scitaminea Syd)引起的甘蔗黑穗病是一种世界性的主要病害。在世界各植蔗区普遍发生,造成感病品种蔗茎产龟和蔗糖分的严重损失,在旱地甘蔗上危害更为严重。公认控制该病经济有效的途径是种植抗病品种。     

甘蔗白条病及其致病菌Xanthomonas albilineans研究进展

由白条黄单胞杆菌Xanthomonas albilineans引起的甘蔗白条病是一种寄生在植物维管组织的系统性细菌病害,在全球多数种植甘蔗的国家或地区普遍发生,对甘蔗产业的发展构成潜在威胁。本研究综述了甘蔗白条病的发生和分布、传播与流行规律以及病原菌生物学与基因组特性、鉴定与检测、遗传多样性和致病机理等方面内容;提出加强抗病种质挖掘与新品种选育推广、加快抗病分子育种进程、切断病害传播途径、加强隔离检验检疫等病害防控策略;此外,评估了该病害在我国蔗区流行暴发的风险,展望今后甘蔗抗病分子育种、病原菌致病机制及其与寄主互作机理等方面的分子基础研究重点与应用前景。     

Characterization,phylogenetic analyses and pathogenicity of Bipolaris setariae associated with brown stripe disease on sugarcane in Yunnan,China

Brown stripe disease is a severe foliar fungal disease of sugarcane worldwide and is widespread in all sugarcane planting areas in China. Brown stripe is a major disease that seriously affects the output and quality of the sugarcane industry in Yunnan Province, China's second-largest sugar base, while the pathogen of this disease remains not yet fully understood. To address this, we isolated and identified the fungi associated with 68 leaf samples showing typical symptoms of brown stripe from 22 sugarcane varieties in different areas of Yunnan Province. A total of 113 isolates were obtained, which were morphologically similar. Of these, 64 representative isolates were sequenced for the internal transcribed spacer region (ITS), GAPDH and EF-1α loci. All representative isolates grouped with the type strain of Bipolaris setariae in the phylogenetic trees inferred with individual and concatenated sequences of ITS, GAPDH and EF1-α. Pathogenicity test results showed that B. setariae strains were able to induce typical symptoms of brown stripe. The results obtained in this study clarify that only B. setariae is associated with sugarcane brown stripe in Yunnan, China. It is recorded here for the first time as a pathogen causing sugarcane brown stripe in Yunnan, and it is able to infect many major cultivars and new varieties, posing a new threat to the sugar industry in Yunnan Province. In addition, these results provide the scientific basis for the future breeding of disease-resistant varieties and effective prevention and control of sugarcane brown stripe disease.     

广东省番石榴褐斑病的病原分离及鉴定

In order to clarify the pathogen causing brown spot of Psidium guajava Linn., and provide a theore-tical basis for effective prevention and treatment of the disease, the pathogen of the brown spot of Psidium guajava Linn. was isolated and identified by molecular and morphological methods. The pathogen was obtained by tissue separation method, and the pathogenicity of the pathogen was determined by Koch′s rule. The morphological characteristics of the conidia of the pathogen were observed by optical microscope, and the sequence of the rDNA-ITS and RPB2 of the pathogen was analyzed by online Blast. The BLAST online alignment showed that the ITS sequence of the pathogen was 100% homologous with multiple strains of Alternaria alternata and Alternaria tenuissima, the homology of the RPB2 sequence of the pathogen with the strains of A. alternata and A. tenuissima reached 99.86%. According to the latest references, A. tenuissima (Fr.) Wiltshire was not an independent species but was a synonym of A. alternata (Fr.) Keissler. Combined with the pathological characteristics of pathogenic fungi, pathogenicity determination and phylogenetic tree analysis, the pathogen of guava brown spot disease in Guangdong was identified as A. alternata.     

甘蔗新品种及主栽品种对褐条病的抗性评价

In 2016-2019, sixty new varieties and 31 main cultivated varieties were evaluated for their resistance to sugarcane brown stripe disease under field condition. The results showed that 32 (53.33%) of 60 new sugarcane varieties were highly to moderately resistant, and 28 (46.67%) were susceptible to highly susceptible. Twenty-one (67.74%) of 31 main cultivated sugarcane varieties were highly to moderately resistant, and ten (32.26%) were susceptible to highly susceptible. This work may facilitate brown stripe resistance breeding and provide new elite resistant varieties for effectively control of sugarcane brown stripe.     

Isolation and genetic characterization of Acidovorax avenae from red stripe infected sugarcane in Northwestern Argentina

Red stripe is a bacterial disease of sugarcane causing important economic losses in Argentina that affects 30 % of the milling stems and consequently the juice quality. In this study, sugarcane leaves exhibiting red stripe symptoms were sampled in the 2008–09 growing season from 13 different sugarcane producing areas of Tucumán and Salta (northwest of Argentina). To achieve the identification and characterization of the causal agent of red stripe, bacterial isolation was performed. Species-specific PCR using Oaf1/Oar1 primers allowed the amplification of a fragment of 550 bp from approximately 50 % of the isolates; 16S rDNA sequences analysis displayed a similarity greater than 99 % with Acidovorax avenae subsp. avenae. By means of RAPD-PCR the presence of at least four different biotypes among the analyzed isolates was detected. Results of pathogenicity test allowed us to confirm A. avenae subsp. avenae as the pathogenic agent for red stripe. This study constitutes the first report on the identification and molecular characterization of this plant pathogen from the Argentina sugarcane production areas. The genetic diversity observed among A. avenae is an important factor to be considered to improve an accurate diagnosis and/or the selection of sugarcane tolerant clones.     

基于GIS的中国小麦条锈病菌越夏区气候区划

 基于多年的气象数据(1980~2001年),首次从制约小麦条锈病菌越夏的温度因子入手,结合寄主小麦因素,利用地理信息系统(Geographical Information System,GIS),对我国小麦条锈病菌越夏区进行较详细的气候区划。本研究从温度条件上明确了全国适合小麦条锈病菌越夏的范围。研究表明,在我国小麦种植区适合小麦条锈病菌越夏的范围很广。其中甘肃、四川、云南、陕西境内适合越夏的地区是连成一片的,甘肃东部除了西边的几个县外其它地方7、8月份最高一旬均温在20~23℃,条锈病菌越夏困难;西藏、青海境内的小麦种植区几乎都适合小麦条锈病菌越夏;贵州境内适合越夏的地区可能和云南越夏区是一个整体。云南适合越夏的地区甚广,且地形复杂,需要进一步调查研究。     

采后胡萝卜腐烂病病原菌鉴定

In October 2012, infected post harvest carrot root were found with decay symptom in several farmer markets around Kunming city of Yunnan Province, China. The symptom was grey white initially, then became brown to black with visible perithecia. According pathogenicity, morphology and sequence of the rDNA internal transcribed spacer region ( ITSI-5.8S-ITS2 ), the pathogen was identified as Ceratocystis fimbriata. The disease has been reported only in Brazil before, this is the first report on C. fimbriata as the pathogen of carrot(Daucus carota) decay post harvest in China .     

雍菜叶斑病病原菌的鉴定

正雍菜(Ipomoea aquatica Forsk.),俗称空心菜,为旋花科(Convolvulaceae)甘薯属(Ipomoea)植物,1年或多年生草本,其嫩茎和叶可食用,有药用价值,在我国南方普遍种植。2015年5月课题组在云南红河州进行病害调查时,在多个雍菜种植田中发现一种新病害,发病快且蔓延迅速,主要为害叶片,严重的田区发病率达54%,严重威胁当地雍菜的产量与质量。为明确病原,我们对田间采集的病样进行了分离培养,并对得到的菌株进行致病性     

禾谷类作物細菌性褐条病病原菌的鉴定

 禾谷类作物细菌性褐条病是我国局部地区禾谷类作物生产上的一种重要病害。通过对几种有关细菌的致病性,细菌学性状和DNA中G+C含量的比较研究,认为发生在我国的水稻细菌性褐条病是由Pseudomonas avenae Manns引起的,供试的黍、粟和稗细菌性褐条病菌都属于P.avenae;小麦上的细菌性褐条病是由Pseudo-monas syringae的一个致病变种引起的。此外,还从看麦娘上分离到一种国内尚无报道的水稻细菌性鞘褐腐病菌Pseudomonas fuscovaginae Tanil et al.。     

兰花褐斑病菌实时荧光PCR检测

兰花褐斑病菌(Acidovorax avenaesubsp.cattleyae)是兰花上一种重要进境检疫性有害生物,可通过植株和种子远距离传播,其传染性强,对兰花危害性大。根据核糖体ITS序列设计了TaqMan-MGB探针并建立了实时荧光PCR检测方法。该方法能够特异性检测兰花褐斑病菌,所有供试的目标菌株检测结果均为阳性,而其它28个对照菌株(含同属内其它种及avenae种下其它亚种)均为阴性。利用该方法从发病兰花植株总DNA中检测到该病菌。本方法灵敏度高,检测极限达9×10-9μg DNA,操作方便快速,结果可靠,适合于口岸兰花的进出境检疫及兰花种苗健康质量控制。