黄芪白粉病发生特点及防治方法

黄芪为野生或栽培种，在河北省为传统中药材之一。黄芪在整个生长期受白粉病的为害相当严重，直接影响产量及品质。１症状黄芪白粉病不仅为害叶片，也为害花蕊、荚果、茎秆等部位，整株布满白粉，到秋天黄芪田发病率达１００％。２病原菌黄芪白粉病是由白粉菌属豌豆白粉菌（ErysiphepisiDC．）侵染而致病的。闭囊壳球形或扁球形，黑褐色，闭囊壳内有数个子囊，子囊椭圆形、倒卵形，无色，有短柄。３发生特点经调查，黄芪白粉病于９月下旬形成有性世代，以子囊果在病残体上越冬。翌年５月份气温达到２０℃以上时，病菌孢子萌发，首先感染二…     

臭椿球针壳后熟过程中的形态学观察

对采自甘肃、北京和成都的臭椿白粉病标样进行了病原菌形态观察比较,结果显示,三个地区采集的标样为同一病原,均为子囊菌亚门、球针壳属真菌———臭椿球针壳。生物学研究表明,成熟的闭囊壳直径为180~225μm;附属丝的数量一般为3~14根,长度4.5~22.5μm,为闭囊壳直径的0.1。成熟的闭囊壳内含有子囊6~35个,多为15~30个。子囊的大小为(45.1~101.3μm)×(22.5~45.2μm)。成熟的子囊孢子多为2个,少见有3个。子囊孢子的大小为(18.5~45.3μm)×(11.25~22.5μm)。温度是影响球针壳后熟的关键因素。4℃条件下,球针壳的成熟速度明显快于室温条件。     

北京地区小麦白粉病初侵染源的研究

各种自然条件下闭囊壳越夏试验结果表明:土壤中,地面和麦茬上,麦垛顶层和底层,室外自然条件下的闭囊壳在秋苗出土前相继变成空壳;室内自然条件下,种子中以及麦垛中层的闭囊壳在越夏季节期间,子囊原生质体结构发生畸变,失去形成子囊孢子的能力。上述各种环境中的闭囊壳先后于7月中旬至9月上旬失去生活力和传病能力,均不能越夏后成为小麦白粉病的初侵染源。在小麦播种时用做过上述各种处理的闭囊壳进行隔离接种试验,试验结果进一步证实了越夏试验结论的正确性。在房山区白粉病发生严重的张坊及十渡一带山区,通过对自生麦苗和小麦秋苗感染白粉病情况的野外调查发现:海拔140m以上山区自生麦苗上的分生孢子是北京地区小麦白粉病在秋苗上的主要侵染源之一。     

小豆白粉病菌的鉴定与小豆品种抗白粉病评价

为明确小豆白粉病病原菌的种类以及小豆种质资源对白粉病的抗性,采用形态学和系统发育学方法对近年来在北京市发生的小豆白粉病病原菌种类进行鉴定,并采用室内苗期人工接种法评价小豆常见栽培品种（系）对白粉病的抗性。结果表明,从北京市采集的感白粉病小豆病样中培养获得病原菌BJ1,该菌能在小豆叶片和茎上产生明显的白色粉斑,分生孢子梗直立,不分枝,分生孢子单细胞,成链状着生于分生孢子梗上,呈椭圆形或卵圆形。通过rDNA-ITS序列系统发育分析,小豆白粉病菌BJ1被鉴定为白粉菌目白粉菌科的苍耳叉丝单囊壳Podosphaera xanthii。室内苗期人工接种条件下,19个供试小豆品种（系）接种小豆白粉病菌BJ1后均可发病,其中9个审定品种均表现为中度感病或高度感病,10个优良品系发病略轻。     

小麦白粉病菌有性生殖与自然群体交配型检测

 本研究根据MAT1-1-1(GenBank登录号HQ171902)和MAT1-2-1(GenBank登录号HQ171899)的部分基因序列设计和筛选其特异性引物,使用PCR方法对2012年度采自四川、陕西、云南、贵州、河南、安徽、江苏、河北、山东和甘肃10个省30个采集地点共516个小麦白粉病菌菌株的交配型基因进行检测。结果显示30个采集地点两种交配型基因都能检测到,其中28个采集地的两种交配型菌株比例(MAT1-1-1 :MAT1-2-1)符合1:1。选择具不同交配型基因的小麦白粉病菌株配对接种,16个随机杂交组合都能产生闭囊壳。对获得的闭囊壳进行子囊孢子释放,均可获得子囊孢子。该研究结果为深入研究有性生殖对小麦白粉病菌株毒性多样性的作用奠定了基础。     

虞美人白粉病的病原鉴定与防病药剂筛选

2020、2021年在河南省商丘市均发现有严重白粉病症状的虞美人,从其病叶上采集病菌,通过形态学观察、致病性试验与rDNA-ITS序列分析对其进行鉴定,并初步筛选适于防治该病的药剂。回接试验证实采集的病菌确为白粉病病原菌,结合形态学观察,通用引物ITS1F和ITS4对病原菌rDNA-ITS序列的PCR扩增、测序,BLAST分析,鉴定河南商丘虞美人白粉病的病原菌为二孢白粉病Golovinomyces cichoracearum。在6种供试药剂中,以43%戊唑醇悬浮剂和45%咪鲜胺水乳剂的防效较好,第2次喷施药剂后7 d防效分别为83.37%、70.06%。     

河南省小麦全蚀病菌的分离及变种类型鉴定

 从河南省10个地市采集的小麦病根样品中分离得到82株病原分离株, 通过形态特征观察、回接致病性测定、以及分子生物学的方法对所分离菌株进行鉴定。其中47个菌株菌丝分支处都形成典型的“∧”状;子囊壳埋生或半埋生, 子囊棍棒状, 子囊孢子线形, 稍弯曲, 无色, 具有5~10个分隔, 大小为68~94 μm×2~4 μm;对82个分离株rDNA-ITS区进行PCR扩增和序列测定, BLAST序列比对结果表明, 47株菌株与小麦全蚀病菌的ITS序列同源性达97%～99%, 据此确定47株菌株为小麦全蚀病菌。应用小麦全蚀病菌4个变种的特异性引物进行PCR扩增都得到禾顶囊壳小麦变种(870 bp)的特异性片段, 鉴定47株菌株均为禾顶囊壳小麦变种 (Gaeumannomyces graminis var.tritici)。     

云南省燕麦白粉病病原鉴定及致病力测定

为明确云南省燕麦白粉病病原菌种类及其致病力,结合形态学和分子生物学对其进行鉴定分析,并测定了该病原菌对21个燕麦品种的致病力。结果表明,燕麦白粉病病原菌孢子梗不分支、无色、基部呈球形膨大,顶端生有成串的分生孢子,分生孢子无色,呈长卵圆形、单胞,大小为18.84~29.12μm×6.53~10.71μm,初步鉴定为禾本科布氏白粉菌Blumeria graminis(DC.)Speer;分子生物学鉴定结果表明病原菌rDNA-ITS区序列与禾本科布氏白粉菌燕麦专化型Blumeria graminis f.sp.avenae的同源性为100%,结合形态特征与分子鉴定最终将云南燕麦白粉病菌鉴定为禾本科布氏白粉菌燕麦白粉病菌专化型。致病力测定结果显示,21个供试燕麦品种发病株率为100.00%,病情指数为91.73~100.00,发病初期平均发病株率和病情指数分别为14.56%和1.75,35 d后发病株率和病情指数分别增长了85.44%和95.74%,表明云南省燕麦白粉病菌的致病力强。     

葡萄白粉病的发生规律及防治

葡萄白粉病在我国各葡萄产区都有发生 ,尤其西北地区及河北、山东受害较重 ,使葡萄产量和品质下降 ,影响经济效益。１主要危害症状白粉病可危害叶片、枝梢及果实等部位 ,而以幼嫩组织最敏感。１．１叶片开始正面产生大小不等不规则的黄色或褪绿色小斑块 ,病斑正反面均可见有一层白色粉状物 ,这是病菌的菌丝体、分生孢子梗和分生孢子。有时产生小黑点 ,是孢子的闭囊壳。粉斑下叶表面呈褐色花斑 ,严重时全叶枯焦。１．２新梢和果梗及穗轴初期表面产生不规则灰白色粉斑 ,后期粉斑下面形成雪花状或不规则的褐斑 ,可使穗轴、果梗变脆 ,枝梢生长受…     

绿豆叶斑病病原鉴定及生物学特性研究

对绿豆叶斑病菌进行形态学和分子特征鉴定,结果表明,分离物在V8培养基上菌落近圆形,菌落边缘泛紫色,分生孢子无色;用通用引物18SF和28SR扩增6个分离物的rDNA-ITS部分序列和测序,并到GenBank(登录号:KM435076)数据库进行比对,6个分离物与变灰尾孢分离物序列相似性为99%,基于形态和分子特征将绿豆叶斑病病原菌鉴定为变灰尾孢。致病性测定结果表明,6个分离物对绿豆‘中绿一号’叶片均致病且存在致病力差异。不同培养基、温度和pH对病原菌生长的影响研究表明,V8培养基最适宜该病菌生长,病菌生长的最适温度为25℃,最适pH为6。     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

Characterization of Sclerotinia minor populations in Texas peanut fields

In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.     

Eyespot of Cereals Revisited: ITS phylogeny Reveals New Species Relationships

Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.     

Transgene herbizidresistente Kulturen

Zusammenfassung Herbizidresistente Kulturpflanzen nehmen unter den derzeit weltweit angebauten gentechnisch veränderten Ackerbaukulturen Sojabohne, Baumwolle, Raps und Mais den weit überwiegenden Anteil ein. Als Ursachen für die rasche Zunahme der Anbauflächen herbizidresistenter Sorten sind unter anderem die Unzulänglichkeiten der für diese Kulturen bestehenden Herbizidlösungen sowie die Zunahme der pfluglosen Bestellverfahren zu sehen. Im Gegenzug hat die Minimalbodenbearbeitung aufgrund der Einführung der Herbizidresistenztechnologie, insbesondere in Sojabohne, ein ausgeprägtes Flächenwachstum erfahren.Als Entscheidungskriterien für die Wahl des Unkrautbekämpfungssystems unter Einbezug des Anbaus herbizidresistenter oder konventioneller Sorten lassen sich aus den Erfahrungen der vergangenen 8 Jahre anführen: Sortenleistung, erhöhte Kulturverträglichkeit und zeitliche Anwendungsflexibilität, Wirkungssicherheit einer Nachauflaufbehandlung in Trockenregionen, Wirkungsbreite, Wirkungsdauer und Bekämpfung resistenter Unkrautbiotypen. Aufgrund fehlender Zulassungen und Kennzeichnungsvorschriften in wichtigen Exportmärkten sind für den Anbau transgener Sorten in Übersee auch Vermarktungseinschränkungen sowie für den Anbau in Europa Haftungs- und Koexistenzregeln wichtige einzelbetriebliche Entscheidungsparameter.Fortschritte erfährt die Herbizidresistenztechnologie kurz- und mittelfristig in der Weiterentwicklung bereits praktizierter Spritzfolgen und Tankmischungen zu Fertigformulierungen der Komplementärherbizide mit residualen Partnern. Zur Bekämpfung und Vorbeugung der Ausbreitung neuer herbizidresistenter Biotypen werden die Komplementärherbizide mit Partnern anderer Wirkungsmechanismen kombiniert. Weitere Entwicklungen sind die Kombination verschiedener transgener Merkmale mit der Herbizidresistenz sowie die Ausweitung von den derzeit dominierenden Kulturen auf weltweit weniger bedeutsame Kulturen, in denen die Entwicklung neuer konventioneller Herbizidwirkstoffe bisher wenig erfolgreich war oder im Verhältnis zum Aufwand nur bedingt attraktiv ist. Für die langfristige Entwicklung könnte die Plastidentransformation zur Verhinderung einer unerwünschten Ausbreitung transgener Merkmale Bedeutung erlangen.     

Pathogenic fungi involved in root rot of peas in the Netherlands and their physiological specialization

Research on root rot pathogens of peas in the Netherlands has confirmed the prevalence ofFusarium solani, F. oxysporum, Pythium spp.,Mycosphaerella pinodes andPhoma medicaginis var.pinodella. Aphanomyces euteiches andThielaviopsis basicola were identified for the first time as pea pathogens in the Netherlands. Other pathogens such asRhizoctonia solani andCylindrocarpon destructans were also found on diseased parts of roots. F. solani existed in different degrees of pathogenicity, and was sometimes highly specific to pea, dwarf bean of field bean, depending on the cropping history of the field.A. euteiches was specific to peas, whereasT. basicola showed some degree of physiological specialization.     

Surveys of cereal diseases and pests in the Netherlands. 3. Monographella nivalis and Fusarium spp. in winter wheat fields and seed lots

Data from surveys of winter wheat fields in the period 1974–1986 and of seed lots in the period 1962–1986 and identifications of diseases on plant samples were compiled to describe the occurrence of snow mould (Monographella nivalis) andFusarium spp. On average,M. nivalis dominated overFusarium spp. The complex ofFusarium spp. constituted mainly ofF. culmorum, followed byF. avenaceum andF. graminearum. M. nivalis was dominant in May on stem-bases and in July on leaves and leaf sheaths. On seedsM. nivalis predominated only in years with low temperatures in July and August.Average brown footrot infection in the field was 4% tillers in May and 5% culms in July. Brown footrot intensity in July was high in cropping seasons with high precipitation in October and with low temperatures in October, November and December. In July during the early eighties, an average of 8% of leaves and 6% of flag leaf sheaths were infected byM. nivalis. Average ear blight incidence was 1.2% glumes infected. Seed contamination by these pathogens averaged 16% in the years 1962–1986. The contamination was high in years with high precipitation in June, July and August. Aspects of cv. resistance and yield loss are illustrated.