茄子绒菌斑病病原菌鉴定及生物学特性研究

本文针对辽宁省近年茄子设施栽培生产上趋重发生的叶部病害——绒菌斑病,对该病的病原菌进行了鉴定及其生物学特性研究。通过病原菌形态学鉴定,柯赫氏法则证病,并对病菌经rDNA-ITS测序,鉴定该病致病菌为真菌灰毛茄钉孢［Passalora nattrassii?(Deighton)U. Braun & Crous］。病菌生物学特性测定结果表明：病菌菌丝生长以PDA+茄叶煎汁培养基为最适;适宜菌丝生长的碳源和氮源分别为可溶性淀粉和胰蛋白胨;适宜温度为25 ℃;最适pH为6;黑暗条件下菌丝生长较好;菌丝致死温度为59 ℃,10min。病菌分生孢子萌发试验结果表明,茄叶汁能明显促进其萌发,碳源以麦芽糖、氮源以硫酸铵最适于孢子萌发,孢子萌发的适宜温度为30 ℃;最适pH为5;光暗交替条件下萌发情况较好;分生孢子致死温度为57 ℃,10min。     

辣椒褐斑病菌生物学特性研究

本文对辣椒褐斑病病原菌Cercospora capsici Heald et Wolf的生物学特性进行了研究,结果表明,不同的营养、温度、pH等条件对菌丝生长和孢子萌发有显著影响。病菌菌丝的生长以PDA培养基为最适;适宜温度为20~25℃,最适温度为25℃;最适pH为8.0~9.0,光照对菌丝生长没有明显的促进作用,菌丝致死温度及时间为55℃ 10 min。分生孢子萌发适宜碳源为1%的蔗糖溶液,适宜氮源为1%的甘氨酸溶液;孢子萌发适宜温度为20~30℃,最适温度25℃;最适pH为5~6,光照对孢子萌发没有明显的促进作用,分生孢子致死温度及时间为52℃10 min。     

龙船花赤枯病病原菌鉴定及其生物学特性测定

采用离体接种法对龙船花叶部病害的一种真菌进行了鉴定和生物学特性测定。结果表明,致病性测定与田间症状相似。通过对病原菌形态学、rDNA-ITS和β-微管蛋白序列的综合分析,确定该病原菌为龙船花拟盘多毛孢(Pestalotiopsis ixorae)。生物学特性测定表明,菌丝生长和分生孢子萌发最适温度为25℃,最适pH分别为6和7;光照更有利于菌丝生长;碳源以可溶性淀粉和D-甘露糖、氮源以硝酸钠最利于菌丝生长;分生孢子在液态水中萌发率最高,为85.3%;菌丝致死温度为50℃10 min,分生孢子致死温度为50℃20 min或55℃5 min。     

哈氏虫道真菌（Ambrosiella hartigii）生物学特性研究

研究了哈氏虫道真菌（Ambrosiella hartigii）的生物学特性。结果表明, 哈氏虫道真菌菌丝生长和产孢均以PDA为最佳培养基, 菌丝生长以甘露醇为碳源、KNO3为氮源最佳, 产孢以蔗糖为碳源、甘氨酸为氮源最佳。菌丝生长和产孢的温度范围分别为10~30 ℃和20~30 ℃, 最适温均为25 ℃, 最适pH为6。菌丝生长、产孢和分生孢子萌发需要黑暗条件。分生孢子萌发最适温度为24~28 ℃, 致死温度为46 ℃10 min, 适宜pH为5.0~6.0。分生孢子在水中不萌发。     

长白山区人参菌核病发生为害及其病原生物学研究

近年来对辽宁和吉林人参主产区病虫害调查发现,人参菌核病发生普遍,为害严重,病田率近90%,病株率5.7%,已经成为长白山区人参主要病害之一。病原生物学研究表明,人参菌核病病原菌菌丝生长及菌核形成的最适温度为20℃,以Czapek培养基为基础的氮源均为蛋白胨。菌丝生长最适pH为4,碳源为山梨醇,最适培养基为胡萝卜培养基;菌核形成的最适pH为6、碳源为果糖,最适培养基为PDA培养基。菌核萌发最佳条件为15~25℃、pH 6~8、碳、氮源分别为乳糖和甘氨酸。菌核在PDA培养基、PSA培养基、人参培养基、燕麦培养基及玉米粉培养基的萌发率均达100%。黑暗条件促进菌丝生长,有利菌核形成及菌核萌发。菌丝致死温度为42℃,菌核致死温度为47℃。     

橡胶狗尾草平脐蠕孢叶斑病病原菌鉴定及生物学特性研究

为明确采自西双版纳景洪地区疑似橡胶麻点病的病原菌,采用组织分离法进行病原菌分离,活体接种法进行致病性测定,通过形态学观察结合rDNA-ITS和GAPDH两个核苷酸片段序列分析,将病原菌确定为狗尾草平脐蠕孢Bipolaris setariae。通过单因子变量试验,对病原菌进行生物学特性研究,结果表明：菌丝生长最适温度为30℃,最适pH为7～8,最适培养基为PDA,菌丝致死温度为53℃,10 min。该病原菌能有效利用多种碳源和氮源,碳源以可溶性淀粉利用率最高,最适氮源为蛋白胨。24 h黑暗条件下培养更有利于菌丝生长。分生孢子萌发的最适温度为28～35℃,最适pH为7～8,28℃黑暗培养2 h后萌发率达到最大,为95.5%,分生孢子致死温度为60℃,10 min。     

高粱链格孢叶斑病菌生物学特性研究

为明确高粱链格孢叶斑病菌Alternaria alternata的生物学特性, 本文采用生长速率法研究了不同营养及环境条件对该病菌生长的影响。试验结果表明:不同培养基上菌丝生长有明显差异, 其中马铃薯蔗糖琼脂培养基(PSA)最适合菌丝生长和孢子产生; 不同碳、氮源条件下菌丝的生长有显著差异, 其中最适宜菌丝生长碳源为葡萄糖, 氮源是蛋白胨; 该病原菌最适宜营养生长的温度为28℃, pH为7; 菌丝的致死温度为47℃; 光照时间对高粱叶斑病菌丝的营养生长没有影响。     

莲雾软腐病病原菌鉴定及其生物学特性研究

莲雾果实采后产生的主要病害为软腐病。本试验对莲雾果实采后软腐病病原菌进行了分离纯化,运用形态学和分子生物学对病原菌进行了鉴定,并研究了其病原菌生物学特性。结果表明,引起莲雾果软腐病的病原菌是异色拟盘多毛孢(Pestalotiopsis versicolor)。生物学特性研究结果表明,该病原菌最适生长温度为25℃,最适菌丝生长的相对湿度为75%~80%,湿度对菌丝生长影响不大,菌丝在pH 3~9之间都能生长,pH 5~6生长较好;最适碳源为麦芽糖,甘露醇不利于菌丝生长;最适氮源为蛋白胨,尿素不利于菌丝生长。该菌对于光照较敏感,完全黑暗能促进其菌丝生长。该菌的孢子致死温度为55℃10min。其生物学特性说明了莲雾果实软腐病病原菌对生存环境具有比较强的适应能力。     

辽宁省玉米北方炭疽病菌的分离鉴定及生物学特性

为明确辽宁省疽病的致病菌及其生物学特性,通过形态学和分子生物学方法鉴定了致病菌,并利用十字交叉法和血球计数板计数法研究了致病菌的生物学特性。系统发育树显示,分离菌株SYND-12与出芽短梗霉Aureobasidium pullulans亲缘关系最近,位于同一分支,并与玉蜀黍出芽短梗霉Aureobasidium zeae聚为一类,分子鉴定结果与形态学鉴定结果一致,表明引起辽宁省玉米北方炭疽病的致病菌为玉蜀黍出芽短梗霉A.zeae(Narita et Hiratsuka)Dingley。该病菌菌丝生长温度范围为10~30℃,最适温度为25℃,最适p H为7,光照条件为全黑暗,适宜的碳、氮源和培养基分别为蔗糖、硝酸钾和马铃薯葡萄糖琼脂培养基;其分生孢子产生的最适碳源为葡萄糖,其它最适宜生长条件与菌丝相同,该病菌在添加不同氮源的水琼脂培养基中均不产生分生孢子;其分生孢子萌发的最适条件为28℃、p H 8、光暗交替,最适碳、氮源分别为麦芽糖和牛肉膏,单一氮源条件对分生孢子的萌发有抑制作用。     

绿豆叶斑病病菌生长特性研究

对采集的绿豆叶斑病病叶,进行了病原菌分离、鉴定及其菌丝生长特性研究.结果表明,绿豆叶斑病病菌为变灰尾孢菌(Cercospora canescens Ell.et Martin);菌丝生长最适培养基是PSA培养基.不同培养基上的菌落颜色不同.病菌生长适宜温度为25～30℃;病菌对pH的适应范围较广;光照有利于菌丝的生长;病菌生长最适碳源为麦芽糖,最适氮源为酵母膏.     

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.     

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China

The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.     

Plant Viruses Transmitted by Whiteflies

One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.     

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.     

Diagnostics,genetic diversity and pathogenic variation of ascochyta blight of cool season food and feed legumes

Molecular diagnostic techniques have been developed to differentiate the Ascochyta pathogens that infect cool season food and feed legumes, as well as to improve the sensitivity of detecting latent infection in plant tissues. A seed sampling technique was developed to detect a 1% level of infection by Ascochyta rabiei in commercial chickpea seed. The Ascochyta pathogens were shown to be genetically diverse in countries where the pathogen and host have coexisted for a long time. However, where the pathogen was recently introduced, such as A. rabiei to Australia, the level of diversity remained relatively low, even as the pathogen spread to all chickpea-growing areas. Pathogenic variability of A. rabiei and Ascochyta pinodes pathogens in chickpea and field pea respectively, appears to be quantitative, where measures of disease severity were based on aggressiveness (quantitative level of infection) rather than on true qualitative virulence. In contrast, qualitative differences in pathogenicity in lentil and faba bean genotypes indicated the existence of pathotypes of Ascochyta lentis and Ascochyta fabae. Therefore, reports of pathotype discrimination based on quantitative differences in pathogenicity in a set of specific genotypes is questionable for several of the ascochyta-legume pathosystems such as A. rabiei and A. pinodes. This is not surprising since host resistance to these pathogens has been reported to be mainly quantitative, making it difficult for the pathogen to overcome specific resistance genes and form pathotypes. For robust pathogenicity assessment, there needs to be consistency in selection of differential host genotypes, screening conditions and disease evaluation techniques for each of the Ascochyta sp. in legume-growing countries throughout the world. Nevertheless, knowledge of pathotype diversity and aggressiveness within populations is important in the selection of resistant genotypes.     

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.