云南、广西三七黑斑病病原链格孢菌的鉴定

正黑斑病是三七栽培生产中常见的一大病害,叶片受害产生近圆形或不规则水浸状病斑,常导致成株落叶、幼苗生长点及茎秆顶端腐烂枯死。其病原一般认为是链格孢属真菌人参链格Alternaria panax Whetzel~([1,2]),也有相关研究证明黑斑病病原为细链格孢Alternaria tenuis Nees~([3]),后定名为链格孢Alternaria alternata Keissl~([4])。本研究利用ITS序列和histone 3部分编码序列的PCR鉴定,结合形态学鉴定,分析三七主产区黑斑病菌的组成和分布情况及几种病原菌的致病力差异,以期为三七黑斑病防治提供理论依据。     

广西百香果采后果腐病病原的鉴定

0 引言 百香果(Passiflora edulis),学名西番莲,为西番莲科(Passifloraceae)西番莲属(Passiflora Linn.)草质藤本植物,原产于南美洲的巴西,在我国主要种植于热带、亚热带地区,具有极高的营养、保健和商品价值[1-2].目前,我国百香果的主栽品种为紫果百香果(Passiflo...     

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.     

苦瓜平脐蠕孢叶斑病病原鉴定

This study was conducted to identify the pathogens causing a new leaf spot disease on bitter gourd. The diseased leaves were collected from bitter gourd plantations around Nanning, Guangxi province. The pathogen causing this disease was identified by pathogenicity, morphology, and combined gene sequences analysis on ITS, TEF and GPD. The morphological characteristics of the pathogen were similar to that of Bipolaris bicolor. The representative isolate was clustered into one clade in phylogenetic tree with B. bicolor, which indicated that the leaf spot of bitter gourd was caused by B. bicolor. This is the first report of a leaf spot disease caused by B. bicolor on bitter gourd.     

苦瓜平脐蠕孢叶斑病病原鉴定

<正>苦瓜是葫芦科苦瓜属植物,在亚洲热带地区、东非、加勒比海等地区均有种植,是药食兼用的重要蔬菜,也是广西南菜北运的主要蔬菜品种~([1,2])。据农业部门不完全统计,广西苦瓜的生产面积超过1.6万公顷,且逐年有增加的趋势。近年来,随着气候的变化,作物栽培面积的扩大,病害的发生也在不断增加。     

河北省苹果果实黑点病的症状与病原研究初报

 为明确河北省苹果果实黑点病的症状类型及其对应的病原菌,本研究对河北省6个市的果园进行了病害调查和样品采集,并对引起不同症状类型的病果进行了病原菌的分离和鉴定。结果表明,河北省的套袋苹果黑点病可以分为四大类型,分别是萼洼黑点型、果面黑点型、果面晕斑型和梗洼褐斑型。除了果面晕斑型为单一病原侵染之外,其他类型的病斑均分离获得3种或3种以上的病原菌。通过形态学分析以及系统发育分析发现,分离的菌株主要为5个不同属的真菌,分别是粉红聚端孢(Trichothecium roseum)、细极链格孢(Alternaria tenuissima)、产菌核枝顶孢(Acremonium sclerotigenum)、尾孢菌(Cercospora sp.)和镰刀菌(Fusarium sp.)。致病性检测表明,粉红聚端孢和细极链格孢的致病力较强,为引起该病害的主要致病菌。而产菌核枝顶孢在河北省造成的症状比之前的报道更加多样化。本研究明确了河北省苹果果实黑点病的主要症状类型及其对应的病原菌,为该病害的流行规律以及综合防控研究奠定了基础。     

莴笋链格孢叶斑病病原鉴定

正莴笋(Lactuca sativa L.var.asparagina Baily)为菊科舌状花亚科莴苣属,又名茎用莴苣,属一年生或两年生草本植物,原产地中海沿岸,约在七世纪初经西亚传入我国,全国各地普遍栽培。2016年分别在河北省及内蒙古莴笋种植区发现一种叶斑病,病斑呈圆形或近圆形、黑褐色、具同心轮纹,     

一种由可可毛色二孢引起的春芋新病害

正可可毛色二孢(Lasiodiplodia theobromae(Pat.) GriffonMaubl.)是由Griffon和Maublanc~([1])在对Botryodiplodia theobromae进行订正的基础上而确立,Alves等~([2])于2008年对这个种又进行了研究并补充了DNA序列信息。可可毛色二孢是一种重要的病原菌,可引起多种植物的枯萎、根腐及焦枯等病害症状~([3,4])。而假可可毛色二     

朱槿茎腐病病原鉴定

Hibiscus rosa-sinensis is an important landscaping plant in Nanning, Guangxi. In 2019, a new stem rot disease was found in H. rosa-sinensis planting area in Nanning. Six diseased samples were collected, and six fungal isolates were isolated and purified from these samples. The fungi were identified as genus Lasiodiplodia based on morphological characteristics of colony and spore. Combined with the text of Koch's rule and a multi-gene phylogenetic tree with sequences of rDNA-ITS, EF-α and β-tubulin, we confirmed that L. theobromae was the pathogen of the new stem rot disease in Nanning. This is the first report on L. theobromae causing H. rosa-sinensis disease in China.     

甜瓜种子携带的链格孢菌种类鉴定及其致病性研究

 采用洗涤检验法和马铃薯葡萄糖琼脂培养基法,从甜瓜种子上分离得到14个链格孢菌分离物。通过菌落形态、产孢表型、分生孢子以及分生孢子梗等形态学观察,结合分析ITS-rDNA和histone 3基因序列,对链格孢菌分离物的种类进行鉴定;甜瓜种子携带的链格孢菌种类分别为细极链格孢(Alternaria tenuissima)、交链格孢(A. alternata)和倒果链格孢(A. obovoidea)。还研究了这些链格孢菌分离物对甜瓜离体叶片的致病性及其对种子发芽的影响;结果表明,除A. obovoidea外,另外两种链格孢菌均对甜瓜离体叶片具有致病性;A. tenuissima和A. alternata的孢子悬浮液对甜瓜种子发芽均有一定的抑制作用。这是国内首次围绕甜瓜种子传带链格孢菌的种类及其致病性开展详细的研究。