玉米顶腐病鉴定

报道了玉米顶腐病发生的系统性症状特点及病原菌鉴定的结果。玉米顶腐病抽穗前主要表?叶缘缺刻、叶片枯死、扭曲卷裹、弯头、顶叶丛生;抽穗后表?为叶片基部腐烂,叶鞘、茎秆腐烂,植株畸形。叶缘缺刻和叶片撕裂是顶腐病区别于其他病害的鉴别性特征。引起玉米顶腐病的病原菌小分生孢子呈假头状着生,而不是串珠状着生,因此,将该病原菌鉴定为亚粘团镰孢霉[Fusarium subglutinans(Wr.&;Reink.)Nelson,Toussoun&;Marasas]。引起茎、叶部两种症状的亚粘团镰孢霉同源性很高,在遗传上具有较高的相似性,是同一病原。与串珠镰孢霉复合侵染可加重病害的发生,其发病率较单独接菌高11.1%。     

江苏省玉米茎腐病菌种类鉴定

作者于1992～1995年,从江苏省玉米主产区采集的玉米茎腐病标样中分离获得105个菌株,经鉴定,致病菌种类有肿囊腐霉(Pythium inflatum)、禾生腐霉(P.graminicola)、串珠镰孢浙江变种(Fusarium moniliforme var.zhejiangensis)、串珠镰孢中间变种(F.moniliforme var.intermedium)、串珠镰孢胶孢变种(F.moniliforme var.subglutinans)、禾谷镰孢(F.graminearum)、拟枝孢镰孢厚膜变种(F.sporotrichioides var.chlamydosporum)、尖孢镰孢芬芳变种(F.oxysporum var.redolens)、接骨木镰孢(F.sambucinum)、茄病镰孢(F.solani)、半裸镰孢(F.semitectum)等11个种或变种。其中串珠镰孢浙江变种出现频率最高,占44.8％,肿囊腐霉和禾生腐霉致病力最强,这两类菌是江苏玉米茎腐病主要病原。     

板栗贮藏期病害发生规律研究

1997～ 1 999年调查 ,浙江省板栗贮藏期病害发生严重 ,病害率高达 44%～ 82 %。果实腐烂多集中在采后 3 0 d内。病害症状有黑腐、褐变、红腐、干腐、湿腐、青腐、点腐 7种 (列表描述症状 ) ,前期以褐变、黑腐为主 ,后期以干腐为主 ;在贮藏过程中引起板栗果实腐烂主要是多种真菌复合侵染所致 ,病原有鞭毛菌亚门腐霉属 ,接合菌亚门毛霉属、犁头霉属 ,半知菌亚门壳二孢属、曲霉属、葡萄霉属、复端孢属、刺盘孢属、镰霉属、青霉属、轮枝孢属的真菌。同一病原能引起不同的症状 ,同一个板栗病果上可分离出几种病原菌。不同板栗品种的被害率不同 ,…     

玉米穗腐病和茎基腐病镰孢菌间相关性的RAPD分析

 利用随机扩增多态性DNA (RAPD)技术对玉米穗腐病和茎基腐病镰孢菌之间的相互关系进行了研究,证实了引起2种病害的串珠镰孢菌同源性很高,在遗传上具有较高的相似性,病菌不易受地域或环境和寄生部位选择作用的影响,同一类型的串珠镰孢菌可以是穗腐病和茎腐病的共同病原菌。禾谷镰孢菌间的遗传变异性很强,易受地域、环境和寄生部位选择作用的影响,出现明显的分化现象,穗腐病和茎基腐病可以由同一禾谷镰孢菌分化类型侵染所致,也可由不同分化类型侵染所致。     

海南玉米穗腐病病原菌分离鉴定及优势种的遗传多样性分析

为了阐明海南省玉米穗腐病病原菌的种类,结合形态学和分子生物学方法对83份病样进行了病原菌的分离和鉴定,最终获得12种病原菌,包括拟轮枝镰孢(Fusarium verticillioides)、层出镰孢(F.proliferatum)、亚粘团镰孢(F.subglutinans)、木贼镰孢(F.equiseti)、新知镰孢(F.andiyazi)、棘孢木霉(Trichoderma asperellum)、拟康宁木霉(T.koningiopsis)、卵孢木霉(T.ovalisporum)、喙刚毛球腔菌(Exserohilum rostratum)、玉蜀黍平脐蠕孢(Bipolaris maydis)、草酸青霉(Penicillium oxalicum)和可可毛色二孢(Lasiodiplodia theobromae)。其中,拟轮枝镰孢分离频率占65.06%,为优势种。以拟轮枝镰孢的EF-1α、histone 3和β-tubulin基因序列为基础进行多基因家系分析,以明确海南省与内陆部分省份不同菌株之间的遗传关系。结果表明,海南省内菌株之间具有丰富的遗传多样性,而且海南省和内陆省份菌株之间存在高频率的基因交流。     

玉米茎腐病病原菌检测方法研究

为提高玉米茎腐病病原菌检测结果的准确性和可信度,以组织分离法做对比,采用分子检测法,对采自田间的189个玉米茎腐病病株进行真菌种类的鉴定和数量的统计。结果表明,分子检测法对腐霉Pythiumspp.的检出频率为29.24%,对镰孢菌Fusariumspp.的检出频率为73.68%,组织分离法对腐霉的检出频率仅为0.58%,对镰孢菌的检出频率为60.82%,两方法的符合率最高仅为35.92%,最低为0。因此,采用组织分离和分子检测相结合的方法可提高玉米茎腐病病原菌鉴定结果的准确性。     

玉米几种重要病害蛋白质组学研究进展

 本文介绍了玉米镰孢菌和黄曲霉穗腐病、腐霉菌苗期病害抗性相关蛋白, 以及在我国曾严重发生的玉米弯孢霉叶斑病菌致病性相关蛋白质组和寄主抗性相关蛋白质组的研究进展, 探讨了利用蛋白质组学技术深入研究玉米-病原菌互作的优势和重要方向。     

丽江山慈菇的一种新病害

丽江山慈菇的鳞茎发现干腐状病害,根据科赫氏法则分离得到病原菌,经鉴定为半知菌亚门丝孢纲丛梗孢目瘤座孢科镰孢霉属长孢直喙镰孢霉。     

黄淮海夏玉米主产区穗腐病病原菌的分离鉴定

为明确我国黄淮海夏玉米主产区玉米穗腐病的病原菌种类、优势种群及虫害、年度、省份对病原菌的影响,以形态学为基础,结合分子生物学方法对2013、2015年随机采自河南、河北、山东3省的155份玉米穗腐病样品进行分离鉴定。结果表明,引起黄淮海夏玉米主产区玉米穗腐病的主要致病菌为镰孢菌Fusarium spp.,包括拟轮枝镰孢F.verticillioides、禾谷镰孢F.graminearum、层出镰孢F.proliferatum、木贼镰孢F.equiseti及藤仓镰孢F.fujikuroi,分离频率分别为49.7%、28.4%、12.3%、3.9%和1.3%;其次为木霉菌Trichoderma spp.,包括哈茨木霉T.harzianum、绿色木霉T.viride和棘孢木霉T.asperellum,分离频率分别为8.4%、3.2%和5.2%;青霉菌Penicillium spp.分离频率较低,为14.2%;曲霉菌Aspergillus spp.包括黑曲霉A.niger和黄曲霉A.flavus,分离频率分别为2.6%和1.9%。研究表明,黄淮海主产区玉米穗腐病优势病原菌为拟轮枝镰孢、禾谷镰孢和木霉菌,不同省份不同年度间病原菌种类及优势病原菌存在差异,虫害能加重玉米穗腐病的发生。     

我国玉米新病害顶腐病的研究初报

 本文报道了我国玉米上的一种新病害玉米顶腐病,是由串珠镰孢亚粘团变种(Fusarium moniliforme var.subglutinans Wr.&Reink)侵染所致。人工接种玉米后表现与田间自然发病症状一致,除侵染玉米外,尚能侵染高粱、苏丹草、谷子、小麦、水稻、珍珠粟等禾本科作物引起顶腐病,并可侵染狗尾草和马唐草等植物。病菌生长的适宜温度25~30℃,最适为28℃;大、小2型分生孢子萌发适宜温度均为25~30℃。木糖、葡萄糖、蔗糖、乳糖、半乳糖和菊糖均是病菌生长的良好碳源。适宜病菌生长的培养基为Richard's、PDA、PSA、玉米粉和燕麦片培养基。田间发病程度因地势而异,低洼易涝地和园田地发病重、坡地和高岗地发病轻。     

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.     

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.     

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.     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

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.     

The use of Solacol® (validamycin) as a growth retardant in the isolation of soil fungi

Solacol^®, a formulation of the antibiotic validamycin, at 0.33% in 2% malt extract agar, reduced the spread of fungi on dilution plates drastically and allowed twice as much incubation time before subculturing; this resulted in an elevated number of species isolated. Using pure cultures of 62 common soil fungi, it was shown that all fast-growing species (exceptPythium ultimum) were efficiently inhibited but not completely suppressed. Inhibition was comparable to that by 0.5% oxgall, though, while this substance completely suppressed several species, Solacol very strongly inhibited onlyGaeumannomyces graminis, Gerlachia nivalis, Harzia acremonioides, Verticillium biguttatum andRhizoctonia solani. In a further experiment each separate constituent of Solacol was tested against 22 fungi at equivalent concentrations. Validamycin strongly inhibitedChaetomium globosum and two Basidiomycetes, though hardly more than the non-ionic detergent which mainly inhibited the other fungi. A few species were, however, more inhibited by Solacol than by the detergent alone. Solacol at 0.33% is a suitable aid in dilution plating of soil fungi, by increasing the number of colonies and species observed.Samenvatting Solacol^®, een formulering van het antibioticum validamycine, remde de groei van schimmels in verdunningsplaten met een concentratie van 0.33% in 2% moutagar en maakte het mogelijk de periode tot afenten met een factor 2 te verlengen; daardoor was het aantal geïsoleerde soorten duidelijk toegenomen. Met reincultures van 62 algemene grondschimmelsoorten werd aangetoond, dat alle snelgroeiende soorten (met uitzondering vanPythium ultimum) voldoende geremd, maar niet volkomen onderdrukt werden. Het remmingspercentage was vergelijkbaar met dat van 0.5% ossegal, hoewel dit laatste sommige soorten volkomen onderdrukte; Solacol remde alleenGaeumannomyces graminis, Gerlachia nivalis, Harzia acremonioides, Verticillium biguttatum enRhizoctonia solani zeer sterk. In een volgend experiment werden de componenten van Solacol t.o.v. 22 fungi apart getoetst in concentraties equivalent aan 0.33% Solacol. Validamycine remde alleenChaetomium globosum en twee basidiomyceten behoorlijk, maar nauwelijks meer dan de niet-ionische uitvloeier, die in hoofdzaak de overige remeffecten veroorzaakte. Enkele soorten werden echter door het complete Solacol veel sterker geremd dan door de uitvloeier alleen. Solacol in een verdunning van 0,33% wordt aanbevolen bij verdunningsplaten voor het isoleren van grondschimmels ten einde het aantal kolonies en soorten te verhogen.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

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.