番茄茎基腐病病原菌的生物学特性

对番茄茎基腐病病原菌生物学特性研究结果表明:病菌菌丝在供试PDA、PSA、2%水琼脂、Richard、番茄煎汁、燕麦片和番茄燕麦等7种培养基中均能良好生长,而在2%水琼脂培养基上生长较为缓慢;菌丝在2～32℃范围内均能生长,最适20℃,致死温度为50℃,10min;菌丝生长的pH范围为3～10,最适为5～7;光照对菌丝生长影响较小。病菌在7种供试培养基上均能产生菌核;菌核在10种供试营养物质中均能萌发,萌发温度范围为5～30℃,最适20℃,致死温度为59℃,10min;菌核萌发pH范围为3～10,最适为7。     

苜蓿毁灭刺盘孢菌的主要生物学特性

苜蓿炭疽病是各苜蓿种植区分布较广的毁灭性病害。毁灭刺盘孢(Colletotrichum destructivum)是苜蓿炭疽病的主要病原菌之一。本试验研究了培养基、碳源、氮源、温度、pH、光照、湿度对毁灭刺盘孢菌菌丝生长、分生孢子产生和萌发的影响。结果表明:该菌菌丝适宜生长的培养基为PDA、PSA和V-8汁;适宜温度范围为28~36℃,最适温度为32℃;适宜pH范围为4~6。该病菌在PDA培养基上,分别以麦芽糖和蛋白胨为碳、氮源,在28℃,pH 6的条件下培养时其产孢能力最强。孢子萌发的最适碳、氮源分别为可溶性淀粉和牛肉膏、蛋白胨;最佳温度28℃;最适pH为6。相对湿度98%以上有利于孢子的萌发。持续光照利于菌丝生长、产孢和萌发。     

辽宁省西瓜炭疽病病原菌鉴定及生物学特性研究

针对西瓜炭疽病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,rDNA ITS测序,鉴定该病致病菌为瓜类炭疽菌（Colletotrichumorbiculare）。生物学特性测定结果表明：病菌菌丝生长最适培养基为PSA; 最适碳、氮源分别为蔗糖和NH4Cl; 最适温度为25℃; 最适pH为6; 黑暗条件利于病菌生长。病菌产孢最适培养基为西瓜茎叶煎汁培养基; 最适碳、氮源分别为蔗糖和NH42SO4; 最适温度为25℃; 最适pH为6; 黑暗条件利于孢子产生。菌丝致死温度为55℃,10min; 分生孢子致死温度为52℃,10min。     

培养条件对柑橘黑斑病菌丝生长的影响

以南丰蜜桔黑斑病菌为实验材料,研究了不同生长环境下病原菌生物学特性。结果表明,病菌在5~35℃的范围内均能生长,25℃为菌丝生长的最适温度。适宜pH值范围为5~7,最适pH值为6;在不同培养基中,菌丝在PDA培养基上生长最快,在OA培养基上菌落周围产生一定量的黄色素;光照时间长短对菌丝生长几乎无影响。     

辣椒胶孢炭疽菌生物学特性初步研究

从广西南宁市采集辣椒炭疽病果实病害标本,进行病原菌分离培养、致病性测定及形态学鉴定,选择引起辣椒炭疽病的病原菌之--胶孢炭疽菌(Colletotrichum gloeosporioides)进行生物学特性研究,结果表明:在测试的不同温度、pH、湿度、光照和营养中,该菌的菌丝体生长和产孢的最适温度分别为25℃和30℃,菌丝体生长和产孢的最适pH值为7,光照对菌丝生长的影响不大,在光暗交替下可促进产孢;分生孢子萌发的最适温度为30℃,最适pH值为7,分生孢子在相对湿度为100%和100%+水滴中能萌发,在100%+水滴中萌发率最高,为99.5%,光照对孢子萌发影响不大;辣椒煎水和辣椒煎水+蔗糖可促进附着胞形成,附着胞在辣椒煎汁中形成率最高,达到90%.     

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。     

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.     

葡萄拟尾孢菌培养特性的研究

经不同培养基培养比较 ,在葡萄叶煎汁培养基上葡萄拟尾孢菌生长最旺盛 ,在CA培养基上产孢量最多。菌丝生长和产孢适宜温度为 20～30℃ ,最适为 25℃ ,低于5℃或高于 40℃病菌停止生长和产孢。菌丝生长、产孢的适宜pH为 6～8,最适 pH 7。在室外自然光照射下菌落生长量最小 ,但产孢量最多 ,室内连续光照有利于菌丝生长。病菌对碳源的利用 ,以可溶性淀粉、乳糖对菌落发育最好 ,山梨糖最差 ;菌丝干重以葡萄糖和可溶性淀粉最好 ,山梨糖最差 ;产孢以菊糖最好。对氮源的利用 ,以硝酸钙为好 ,对尿素的利用能力最差 ,不能利用亚硝酸钠 ;产孢以白氨酸最好 ,菌丝干重以丙氨酸和天冬氨酸最好     

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。     

山葵墨入病菌生物学特性研究

对山葵墨入病病株进行分离鉴定,明确其病原菌为山葵茎点霉菌(Phoma wasabiae Yokogi)。对该菌生物学特性研究结果表明,适宜该菌生长的培养基为PDA培养基,不同的温度、pH、光照等条件对山葵茎点霉菌的菌丝生长和产孢有显著的影响。该菌适宜的生长温度为19-25℃,最适温度为22℃;适宜生长的pH为6.0-9.0,最适pH7-8;该菌在黑暗条件下比在光照和光暗交替处理下生长快,且产孢的能力相对强;致死温度为55℃。10min。     

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.     

Tumours of Begonia and some other ornamentals,induced by Corynebacterium fascians

In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.