DOCSLIB.ORG

Aphid Vectors and Grass Hosts of Barley Yellow Dwarf Virus and Cereal Yellow Dwarf Virus in Alabama and Western Florida by Buyun

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Aphid Vectors and Grass Hosts of Barley Yellow Dwarf Virus and Cereal Yellow Dwarf Virus in Alabama and Western Florida by Buyun AphidVectorsandGrassHostsofBarleyYellowDwarfVirusandCerealYellow DwarfVirusinAlabamaandWesternFlorida by BuyungAsmaraRatnaHadi AdissertationsubmittedtotheGraduateFacultyof AuburnUniversity inpartialfulfillmentofthe requirementsfortheDegreeof DoctorofPhilosophy Auburn,Alabama December18,2009 Keywords:barleyyellowdwarf,cerealyellowdwarf,aphids,virusvectors,virushosts, Rhopalosiphumpadi , Rhopalosiphumrufiabdominale Copyright2009byBuyungAsmaraRatnaHadi Approvedby KathyFlanders,Co-Chair,AssociateProfessorofEntomologyandPlantPathology KiraBowen,Co-Chair,ProfessorofEntomologyandPlantPathology JohnMurphy,ProfessorofEntomologyandPlantPathology Abstract Yellow Dwarf (YD) is a major disease problem of wheat in Alabama and is estimated to cause yield loss of 21-42 bushels per acre. The disease is caused by a complex of luteoviruses comprising two species and several strains, including Barley yellowdwarfvirus (BYDV),strainPAV,and Cerealyellowdwarfvirus (CYDV),strain RPV. The viruses are exclusively transmitted by aphids. Suction trap data collected between1996and1999inNorthAlabamarecordedthe presence of several species of aphidsthatareknowntobeB/CYDVvectors. Aphidsweresurveyedinthebeginningofplantingseasonsinseveralwheatplots throughout Alabama and western Florida for four consecutive years. Collected aphids wereidentifiedandbioassayedfortheirB/CYDV-infectivity.Thissurveyprogramwas designedtoidentifytheaphid(Hemiptera:Aphididae)speciesthatserveasfallvectorsof B/CYDVintowheatplanting.From2005to2008,birdcherry-oataphid, Rhopalosiphum padi (L.), rice root aphid, Rhopalosiphum rufiabdominale (Sasaki), and greenbug, Schizaphis graminum (Rondani), were consistently found between October and December. The species of aphids and their timing of appearance in wheat plots were consistentwithflightdatacollectedinNorthAlabamabetween1996and1999.Both R. padi and R.rufiabdominale werefoundtocarryandtransmitBYDV-PAVandCYDV- RPV. Low overall numbers of collected aphids and low proportion of infective aphid madeitdifficulttoconclusivelyidentifytheprimaryvectorofB/CYDVinAlabama. ii The source of summer/fall infection of BYDV and CYDV is not known in Alabama.Pasturegrassesmayprovideameansofsurvivalduringsummermonthswhen wheatisnotavailableinAlabama.Varietyplotsofthreepasturegrassesweresampledin summerbetween2007and2009forB/CYDVandaphids.Ofthethreepasturegrasses surveyed, bahiagrass was found to consistently harbor BYDV-PAV and CYDV-RPV, whilelimpograsswasfoundtoharborBYDV-PAVandCYDV-RPVirregularly.Thisis thefirstreportofBYDVonbahiagrassandlimpograss.Noaphidswerefoundduringthis studyonlimpograssandgamagrasswhiletheaphid Siphaflava (Forbes)wasfoundin twooutofthreeyearsofsurveyonbahiagrass. iii Acknowledgments Itisapleasuretoacknowledgetheencouragement,forbearanceandexpertiseof manythatcarriedthisworktoitscompletion.Iamdeeplyindebtedtotheco-chairofmy advisory committee, Kathy Flanders, for her patience and expertise in guiding me throughthelongandwindingroad,literally,offieldresearchandacademicjourney.Her genuine friendship and mentorship are invaluable for me. Co-chair Kira Bowen and committeememberJohnMurphybothtrainedmeinacquiringnewskillscrucialforthis work.Theirexamplesofcriticalandbroadthinking,andtotakelifewithapinchofsalt (andanextrahelpingofdarkhumor),willsurelyhavetheirprintsinmycareerandlife. SusanHalbertfromFloridaDepartmentofPlantIndustrysetmeoffonmypathinaphid identification,ofwhichIreallyamgrateful.TheworkisfundedbytheAlabamawheat andfeedgraincheck-offcommittee. AspecialthankstoThomasWilliamsoftheNavigators.Hisfriendshipandthe exemplary life that he lived before my eyes are precious forever. Ryan Schumacher, NirmalAndrews,PaulDawson,TrafinaJadhaf,FranklinQuarcoo,MosesNtam,Michael Madan Mohan, Saisree Uppala and Dayton Cook have surrounded me with encouragementsandjoyofsharedlives. MyfamilyinIndonesia,asalways,hasbeenaconstantsourceofstrength and wisdom.Theyespeciallyknowhowtoteachmehumilityandputmyimportantworkin iv perspective,“So,youaregoingtogetadegreeforcrawlingaroundfieldsandcounting insects?” Andasforadedication,I’mtryingstilltoheedanitinerantpreacher’swordslong ago, “ …whether you eat or drink or whatever you do (e.g. do research and write a dissertation),doitallforthegloryofGod.” v TableofContents Abstract...............................................................................................................................ii Acknowledgments..............................................................................................................iv ListofTables.....................................................................................................................ix ListofFigures.....................................................................................................................x ListofAbbreviations.........................................................................................................xi 1 Introduction.................................................................................................................1 2 LiteratureReview........................................................................................................4 2.1 Thehosts..............................................................................................................5 2.2 Theviruses...........................................................................................................5 2.3 Thevectors...........................................................................................................8 2.3.1 Taxonomyandlifecycle...............................................................................8 1.1.1 Aphidmovement.........................................................................................10 1.1.2 BYDVandCYDVvectorsinAlabama......................................................12 2.4 Virus-hostrelationships......................................................................................19 2.4.1 Symptomformation....................................................................................19 2.4.2 Physiologyofyieldreductionininfectedplants.........................................23 2.4.3 Virussystemicmovementinsidetheplant.................................................24 2.5 Host-vectorrelationships....................................................................................25 2.5.1 Aphidreproductiononhealthyhosts..........................................................25 vi 2.5.2 Aphiddispersalandhostfindingstrategy...................................................26 2.6 Virus-vectorrelationships..................................................................................28 2.7 Virus-vector-hostrelationships..........................................................................30 2.7.1 Aphidpopulationdynamicsandalataeproductiononinfectedhost..........30 2.7.2 Aphidattractiontoinfectedhosts...............................................................31 2.7.3 Aphidfeedingbehavioroninfectedhosts..................................................32 2.8 Environmentalrelationships...............................................................................33 2.8.1 Temperatureandrainfall.............................................................................33 2.8.2 Cropmanagementpractices........................................................................35 2.8.3 Otherfieldcharacteristics...........................................................................38 2.8.4 Naturalenemies..........................................................................................39 2.8.5 Plantresistanceandtolerance.....................................................................40 2.8.6 Chemicalcontrolandforecastingschemes.................................................46 3 Long-TermGoal,ObjectivesandHypothesis...........................................................60 4 Species Composition of the Aphid Vectors of Barley Yellow Dwarf Virus and CerealYellowDwarfVirusinAlabamaandWesternFlorida.................................61 4.1 Introduction........................................................................................................61 4.2 Methodology......................................................................................................62 4.3 Results................................................................................................................65 4.4 Discussion..........................................................................................................67 4.5 Conclusion..........................................................................................................75 5 Perennial Pasture Grasses as Hosts of Barley Yellow Dwarf Virus and Cereal YellowDwarfVirus..................................................................................................81 vii 5.1 Introduction........................................................................................................81 5.2 Methodology......................................................................................................83 5.3 Results................................................................................................................87 5.4 Discussion..........................................................................................................88 5.5 Conclusion..........................................................................................................92 References.........................................................................................................................95
Load more

Recommended publications
  • Russian Wheat Aphid
    Fact sheet Russian wheat aphid What is Russian wheat aphid? Russian wheat aphid (Diuraphis noxia) is a soft bodied insect that feeds mainly on wheat and barley, but can attack most cereal crops. If this pest enters Australia, it has been estimated that it could cause significant damage to crops, resulting in up to 75% yield losses. è è What does it look like? The aphid is small (up to 1.8 mm long), has a ‘needle-like’ mouthpart, and is light green in colour. The body is elongated compared with other cereal Bugwood.org Frank Peairs, Colorado State University, Wingless adult Russian wheat aphid, showing lack of aphid species. Adults can be winged or wing-less. siphuncles (‘exhaust pipes’ – circled) and presence of a Juveniles (nymphs) look similar to adults but lack ‘double tail’ end (cauda – arrowheads) wings. Characteristic features include dual structures at the rear (cauda) of the insect giving it a ‘double-tail’ appearance (see arrowheads in image top right) and lack visible siphuncles (‘exhaust pipes’ – circles in images on right) that are characteristic for most aphids. What can it be confused with? If it were present, Russian wheat aphid could be found with other cereal aphids on crops. The elongated body shape and lack of ‘exhaust SARDI pipes’ distinguish this aphid from common cereal Adult Oat aphid, with siphuncles (‘exhaust pipe’) structures species (compare top image to middle image). (circled) and no double tail What should I look for? Whilst feeding, the aphid injects salivary toxins into the plant tissue causing the leaves to roll up and white, purple or yellowish streaks to form.
    [Show full text]
  • Neonicotinoid Insecticide Seed Treatments in Soybean: an Indirect Means of Reducing CMV Incidence in Processing Green Beans
    Neonicotinoid insecticide seed treatments in soybean: an indirect means of reducing CMV incidence in processing green beans 2018 Wisconsin Agribusiness Classic January 11, 2018 Russell L. Groves1 and Brian A. Nault2 1Department of Entomology, 537 Russell Laboratories 1630 Linden Drive, Madison, WI 53706 2Department of Entomology, 525 Barton Laboratories 630 W. North Street, Geneva, NY 14456 Presentation Outline – New Project • Chronology of green bean viruses in Wisconsin • Dynamics of virus spread • 2017 – 2018 Research Objective – Determine whether low populations of soybean aphid, Aphis glycines, correspond with low infection rates of recent virus infections (Cucumber mosaic virus) • Future directions and new steps Total Impact of Specialty Crop Production and Processing (Economic activity in $ millions per year) Keene and Mitchell, 2010 Processing Snap Bean: Pest Phenology in Wisconsin European corn borer Potato leafhopper Seed corn maggot Harvesting Planting 5/5 5/19 6/2 6/16 6/30 7/14 7/28 8/11 8/25 9/8 9/22 10/6 Date Biology and Distribution of the Soybean aphid (Aphis glycines Matsumura) © Merle Shepard, Bugwood.org North Central Region – Aphid Suction Trap Network Weekly captures of dispersing aphid species. Dr. David Voegtlin, Illinois Natural History Survey Acyrthosiphon pisum "Pea aphid" Aphis craccivora "Black legume aphid" Aphis glycines "Soybean aphid" Aphis gossypii "Cotton- melon aphid" Aphis helianthi "Sunflower or dogwood aphid" Aphis nasturtii "Buckthorn - potato aphid" Aphis spiraecola "Spiraea aphid" Brachycaudus
    [Show full text]
  • Areawide Pest Management of Cereal Aphids in Dryland Wheat Systems of the Great Plains, USA
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Panhandle Research and Extension Center Agricultural Research Division of IANR 2008 Areawide Pest Management of Cereal Aphids in Dryland Wheat Systems of the Great Plains, USA Kristopher Giles Oklahoma State University, [email protected] Gary L. Hein University of Nebraska-Lincoln, [email protected] Frank Peairs Colorado State University - Fort Collins Follow this and additional works at: https://digitalcommons.unl.edu/panhandleresext Part of the Agriculture Commons Giles, Kristopher; Hein, Gary L.; and Peairs, Frank, "Areawide Pest Management of Cereal Aphids in Dryland Wheat Systems of the Great Plains, USA" (2008). Panhandle Research and Extension Center. 33. https://digitalcommons.unl.edu/panhandleresext/33 This Article is brought to you for free and open access by the Agricultural Research Division of IANR at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Panhandle Research and Extension Center by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 19 Areawide Pest Management of Cereal Aphids in Dryland Wheat Systems of the Great Plains, USA KRISTOPHER GILES, 1 GARY HEIN2 AND FRANK PEAIRS3 1Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, Oklahoma, USA 2Department of Entomology, University of Nebraska Panhandle R&E Center, Scottsbluff, Nebraska, USA 3Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, Colorado, USA Introduction: Description of the Problem and Need for an Areawide Pest Management Approach In the Great Plains of the USA from Wyoming to Texas, dryland winter wheat either is regularly grown continuously or is followed by a year of fallow in semi-arid locales (Royer and Krenzer, 2000).
    [Show full text]
  • Early Season Population Dynamics and Residual Insecticide Effects on Bird Cherry-Oat Aphid, Rhopalosiphum Padi in Arkansas Winte
    University of Arkansas, Fayetteville ScholarWorks@UARK Theses and Dissertations 5-2012 Early Season Population Dynamics and Residual Insecticide Effects on Bird Cherry-oat Aphid, Rhopalosiphum padi in Arkansas Winter Wheat Beven McWilliams University of Arkansas, Fayetteville Follow this and additional works at: http://scholarworks.uark.edu/etd Part of the Entomology Commons, and the Plant Pathology Commons Recommended Citation McWilliams, Beven, "Early Season Population Dynamics and Residual Insecticide Effects on Bird Cherry-oat Aphid, Rhopalosiphum padi in Arkansas Winter Wheat" (2012). Theses and Dissertations. 246. http://scholarworks.uark.edu/etd/246 This Thesis is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of ScholarWorks@UARK. For more information, please contact [email protected], [email protected]. EARLY SEASON POPULATION DYNAMICS AND RESIDUAL INSECTICIDE EFFECTS ON BIRD CHERRY-OAT APHID, RHOPALOSIPHUM PADI IN ARKANSAS WINTER WHEAT EARLY SEASON POPULATION DYNAMICS AND RESIDUAL INSECTICIDE EFFECTS ON BIRD CHERRY-OAT APHID, RHOPALOSIPHUM PADI IN ARKANSAS WINTER WHEAT A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Entomology By Beven McWilliams Rhodes College Bachelor of Science in Biology, 2008 May 2012 University of Arkansas ABSTRACT Bird cherry-oat aphid is a common pest of Arkansas winter wheat. This aphid vectors barley yellow dwarf virus which may cause extensive crop damage and yield loss when wheat is infested by virulent aphids in the fall. Some suggest this damage may be avoided using insecticide seed treatments if growers are unable to delay planting, as is recommended.
    [Show full text]
  • Population Growth and Damage Caused by Rhopalosiphum Padi (L.) (Hemiptera, Aphididae) on Different Cultivars and Phenological Stages of Wheat
    Neotrop Entomol (2013) 42:539–543 DOI 10.1007/s13744-013-0158-9 PEST MANAGEMENT Population Growth and Damage Caused by Rhopalosiphum padi (L.) (Hemiptera, Aphididae) on Different Cultivars and Phenological Stages of Wheat 1 1 2 1 1 1 MSAVARIS ,SLAMPERT ,JRSALVADORI ,DLAU ,PRVSPEREIRA ,MASMANIOTTO 1Embrapa Trigo, Lab de Entomologia, Passo Fundo, RS, Brasil 2Univ de Passo Fundo, Fac de Agronomia e Medicina Veterinária, Passo Fundo, RS, Brasil Keywords Abstract Aphids, damage, Triticum aestivum,yield Among the aphids associated with wheat and other winter cereals, Correspondence Rhopalosiphum padi (L.) is currently the predominant species in the wheat PRVS Pereira, Embrapa Trigo, Lab de growing region of southern Brazil. The damage caused by this aphid occurs Entomologia, Caixa Postal 451, CEP by direct feeding and/or by the transmission of pathogenic viruses, such as 99001-970, Passo Fundo, RS, Brasil; [email protected] the Barley/Cereal yellow dwarf virus. In order to estimate the direct damage caused by R. padi on wheat, we evaluated the population growth Edited by Jorge B Torres – UFRPE of this aphid during the tillering and elongation stages and its effects on Received 22 June 2012 and accepted 29 July grain yield components. The experiment was conducted in a screenhouse 2013 with three wheat cultivars (BRS Guabiju, BRS Timbaúva, and Embrapa 16). Published online: 29 August 2013 The effect of a period of 16 days, starting from an infestation of 40 aviruliferous aphids/plant, was evaluated and compared to non-infested * Sociedade Entomológica do Brasil 2013 plants. In both stages, the population growth of R.
    [Show full text]
  • Hippodamia Variegata (Goeze) (Coleoptera: Coccinellidae) Detected in Michigan Soybean Fields
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by ValpoScholar The Great Lakes Entomologist Volume 38 Numbers 3 & 4 - Fall/Winter 2005 Numbers 3 & Article 8 4 - Fall/Winter 2005 October 2005 Hippodamia Variegata (Goeze) (Coleoptera: Coccinellidae) Detected in Michigan Soybean Fields Mary M. Gardiner Michigan State University Gary L. Parsons Michigan State University Follow this and additional works at: https://scholar.valpo.edu/tgle Part of the Entomology Commons Recommended Citation Gardiner, Mary M. and Parsons, Gary L. 2005. "Hippodamia Variegata (Goeze) (Coleoptera: Coccinellidae) Detected in Michigan Soybean Fields," The Great Lakes Entomologist, vol 38 (2) Available at: https://scholar.valpo.edu/tgle/vol38/iss2/8 This Peer-Review Article is brought to you for free and open access by the Department of Biology at ValpoScholar. It has been accepted for inclusion in The Great Lakes Entomologist by an authorized administrator of ValpoScholar. For more information, please contact a ValpoScholar staff member at [email protected]. Gardiner and Parsons: <i>Hippodamia Variegata</i> (Goeze) (Coleoptera: Coccinellidae) D 164 THE GREAT LAKES ENTOMOLOGIST Vol. 38, Nos. 3 & 4 HIPPODAMIA VARIEGATA (GOEZE) (COLEOPTERA: COCCINELLIDAE) DETECTED IN MICHIGAN SOYBEAN FIELDS Mary M. Gardiner1 and Gary L. Parsons2 ABSTRACT Since its initial detection near Montreal, Canada in 1984, the variegated lady beetle Hippodamia variegata (Goeze) (Coleoptera:Coccinellidae) has spread throughout the northeastern United States. In 2005, this immigrant Old World species was detected in Michigan for the first time. Twenty-nine adults were found in soybean fields in 4 counties: Ingham, Gratiot, Kalamazoo, and Saginaw.
    [Show full text]
  • The Ecology of the Bird Cherry-Oat Aphid, Rhopalosiphum Padi (L.)
    WÅITT. INSTI]'IjTE t8't,n3 LIIìR,\fiY The Ecology of the Bird Cherry-Oat Àphid, RhopaTosiphun padi (t. ) (Heniptera: Aphididae) in the Low Rainfall llheat Belt of South Australia. By PauI Joseph De Barro B.Ag.Sc. (Hons) The University of Àdelaide A thesis submitted for the Degree of Doctor of Philosophy in the Faculty Agricultural and Natural Resource Sciences at The University of Àdelaide. Department of crop Protection Waite Àgricultural Research fnstitute The University of Adelaide December L99I TO ELIZÀBETH ÀNNE CARTER Table of Contents Page SUI,TII{ÀRY xi DECI,ÀRATION xiii ÀCKNO¡{LEDGT,TENTS xiv INTRODUCTION 1 RESEÀRCH PI-ÀN 3 CTIÀPTER 1 CEREÀL APHIDS IN AUSTRALIÀ 5 CHÀPTER 2 BÀRLEY YELLOI,{ DÍ{ÀRF VIRUS IN AUSTRÀLIA 15 CTIÀPTER 3 A CHEAP LIGHTWEIGHT EFFICIENT VÀCUUM SÀMPLER. 24 Abstract 24 Introduction 24 Materials and Methods 24 Results and Discussion 27 CHÀPTER 4. KARYOTYPES OF CEREAL ÀPHIDS IN SOUTH AUSTRÀLIÀ WTTH SPECIÀL REFERENCE TO R. MATDÏg. 30 Àbstract 30 Introduction 30 Materials and Methods 33 Results 34 Discussion 34 CHÀPTER 5. STUDIES ON THE BIOLOGY OF ÀPTEROUS R. PADI. 38 Àbstract 38 Introduction 38 Materials and Methods 39 Results and Discussion 4I CHÄPTER 6. THE ROLE OF REFUGE AREÀS IN THE PHENOLOGY OF R. PADT IN LOhI RÀINFÀLL CROPPING AREAS OF SOUTH ÀUSTRÀLIÀ. 44 Abstract 44 Introduction 44 Materials and Methods 49 Results 53 Discussion 65 111 CHÀPTER 7 THE ROLE OF TEMPERÀTURE, PHOTOPERIOD, CROWDING ÀND PLÀNT QUALITY ON THE DEVELOPMENT OF THE ÀLATE EXULE FORM OF R. PADÏ. 69 Abstract 69 Introduction 70 Materials and Methods 7L Results 77 Discussion 88 CIIÀPTER 8.
    [Show full text]
  • A Study of the Biology of Rhopalosiphum Padi (Homoptera: Aphididae) in Winter Wheat in Northwestern Indiana J
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Faculty Publications: Department of Entomology Entomology, Department of 1987 A STUDY OF THE BIOLOGY OF RHOPALOSIPHUM PADI (HOMOPTERA: APHIDIDAE) IN WINTER WHEAT IN NORTHWESTERN INDIANA J. E. Araya Universidad de Chile John E. Foster University of Nebraska-Lincoln, [email protected] S. E. Cambron Purdue University, [email protected] Follow this and additional works at: http://digitalcommons.unl.edu/entomologyfacpub Part of the Entomology Commons Araya, J. E.; Foster, John E.; and Cambron, S. E., "A STUDY OF THE BIOLOGY OF RHOPALOSIPHUM PADI (HOMOPTERA: APHIDIDAE) IN WINTER WHEAT IN NORTHWESTERN INDIANA" (1987). Faculty Publications: Department of Entomology. 543. http://digitalcommons.unl.edu/entomologyfacpub/543 This Article is brought to you for free and open access by the Entomology, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Faculty Publications: Department of Entomology by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 1987 THE GREAT LAKES ENTOMOLOGIST 47 A STUDY OF THE BIOLOGY OF RHOPALOSIPHUM PADI (HOMOPTERA: APHIDIDAE) IN WINTER WHEAT IN NORTHWESTERN INDIANAI J. E. Araya2, J, E. Foster3, and S. E. Cambron 3 ABSTRACT Periodic collections of the bird cherry-oat aphid, Rhopalosiphum padi, dtring two years revealed small populations on winter wheat in Lafayette, Indiana. The greatest numbers were found on volunteer wheat plants before planting. In the autumn, aphids were detected on one-shoot plants by mid-October and also early March. The populations remained small until mid-June. We conclude that the aphid feeding did not significantly affect the plants, but helped spread barley yellow dwarf virus.
    [Show full text]
  • Full Article
    CZECH MYCOLOGY Publication of the Czech Scientific Society for Mycology Volume 48 August 1995 Number 2 Natural occurrence of entomopathogenic fungi on Aphids at an agricultural field site TOVE STEENBERG and J0RGEN E il e n b e r g Department of Ecology and Molecular Biology Royal Veterinary and Agricultural University Biilowsvej 13, 1870 Frb. C., Denmark « Steenberg T. and Eilenberg J. (1995): Natural occurence of entomopathogenic fungi on Aphids at an agricultural field site. - Czech Mycol. 48: 89-96 The occurrence of insect pathogenic fungi on cereal aphids (Sitobion avenae, Rhopalosiphum padi and Metopolophium dirhodum) and other aphid species was studied at an agricultural field site over two years. Aphids were sampled from crops (Tricitum sativum, Avena sativa and Secale cereale) and weeds (Chenopodium album, Polygonum spp., Lamium sp., Capsella bursa-pastoris and others) and the following fungal species were documented: Erynia neoaphidis, Entomophthora planchoniana, Conidiobolus obscurus, Conidiobolus thromboides, Neozygites fresenii and Verticillium lecanii. Epizootic development from mid July onwards occurred in a population of S. avenae. The dominant fungus species in 1993 was E. neoaphidis, and in 1994 E. planchoniana. It was possible to infect S. avenae with E. neoaphidis originating from other aphid species. K ey words: Entomopathogenic fungi, cereal aphids, weeds, Erynia neoaphidis, Entomoph­ thora planchoniana Steenberg T. a Eilenberg J. (1995): Přirozený výskyt entomopotogennich hub na mšicích v polních podmínkách. - Czech Mycol. 48: 89-96 Po dobu dvou let byl v polních podmínkách sledován výskyt hub patogenních pro hmyz na mšicích na obilninách - kyjatce osenní (Sitobion avenae), mšici střemchové (Rhopalosiphum padi) a kyjatce travní (Metopolophium dirhodum) a dalších druzích mšic.
    [Show full text]
  • Maize Aphid (330)
    Pacific Pests and Pathogens - Fact Sheets https://apps.lucidcentral.org/ppp/ Maize aphid (330) Photo 1. Colonies of the maize aphid, Rhopalosiphum maidis, on the tassles of maize. Photo 2. Maize aphids, Rhopalosiphum maidis, Photo 4. Colony of maize aphid, Rhopalosiphum maidis, with numerous 'mummies', swollen parasitised individuals. The papery skin of some has collapsed after Photo 3. Adult maize aphid, Rhopalosiphum maidis, the exist of the parasitoid. Common Name Maize aphid, corn leaf aphid, green corn aphid Scientific Name Rhopalosiphum maidis Distribution Worldwide. In tropical, subtropical and temperate regions. Asia, Africa, North, South and Central America, the Caribbean, Europe, Middle East, Oceania. It is recorded from Australia, Cook Islands, Fiji, New Caledonia, New Zealand, Northern Marianna Islands. Papua New Guinea, Solomon Islands, Tonga, and Wallis and Futuna. Hosts Maize, sorghum, barley, millet, and many grasses. Symptoms & Life Cycle Aphids suck the sap of plants, often occurring in large numbers, causing plants to yellow and wilt. Sooty mould fungi develop on honeydew discharged by the aphids that falls onto the leaves. Large numbers of aphids occur on maize 'tassels' (the male flowers) preventing the development of pollen (Photo 1). Male aphids are very rare, and females give birth to living young without mating. Nymphs are light green, darkening to bluish or olive green adults, with black antennae and legs, and purple areas at the base of the two upright, backward-pointing tubes ('cornicles') at the rear of the body (Photo 2). The adults are somewhat rectangular, about 2 mm long, mostly without wings (Photo 3). Nymphs become adults within 7-14 days, depending on temperatures.
    [Show full text]
  • Cereal Aphids G
    G1284 (Revised August 2005) Cereal Aphids G. L. Hein, Extension Entomologist, J. A. Kalisch, Extension Technologist, and J. Thomas, Research Coordinator to living young. A female may produce two to three young Identification and general discussion of the cereal per day under warm conditions, and females may mature in aphid species most commonly found in Nebraska small 7-10 days. This tremendous reproduction potential can result grains, corn, sorghum and millet. in rapid aphid population buildup. Males of some species are seldom if ever seen. Cereal aphids can be a serious threat to several Nebraska Both winged and wingless aphids may be present in the crops. Aphid feeding may cause direct damage to the plant or field. Winged forms are produced when the quality of the host result in transmission of plant diseases. Aphids also may cause plant declines, such as at maturity. Other factors, including damage by injecting toxic salivary secretions during feeding. temperature, photoperiod or seasonality, and population density In Nebraska the most serious cereal aphid problems result also may be involved. The ability of aphids to use flight for from Russian wheat aphid infestations on wheat and barley dispersal is an important factor that contributes to the status and greenbug infestations on sorghum and to a lesser extent of these insects as pests. on wheat. Growers must monitor their crops for these aphids. Greenbug, Schizaphis graminum (Rondani) Several other cereal aphid species also may be present, but they seldom cause significant damage. Accurate aphid identi- The greenbug is a light green aphid with a dark green fication is necessary to make the best management decisions.
    [Show full text]
  • Airborne Multispectral Remote Sensing for Russian Wheat Aphid
    AIRBORNE MULTI-SPECTRAL REMOTE SENSING FOR RUSSIAN WHEAT APHID INFESTATIONS Norm Elliott1, Mustafa Mirik2, Zhiming Yang3, Tom Dvorak4, Mahesh Rao3, Jerry Michels2, Vasile Catana2, Mpho Phoofolo2, Kris Giles2, and Tom Royer2 1USDA-ARS-PSRL 1301 N. Western Rd., Stillwater, OK 74074 [email protected] 2Texas Agricultural Experiment Station 2301 Experiment Station Rd., Bushland, TX 79012 [email protected], [email protected] 3Oklahoma State University Stillwater, OK 74078 [email protected], [email protected] [email protected], [email protected] [email protected], [email protected] 4University of Iowa Iowa City, IA 52243 [email protected] ABSTRACT The Russian wheat aphid (RWA) is a severe pest of wheat in the High Plains region of the United States. Remote sensing could be effective for detecting RWA infestations for pest management decision-making. We evaluated an airborne multi-spectral remote sensing system for its ability to differentiate varying levels of injury caused by RWA infestation in winter wheat fields. Two study fields were located in southeastern Colorado in spring 2004, and two fields were located in far western Oklahoma in spring 2005. In each field, RWA density and plant damage were determined for 20-24 3x3 m plots with varying levels of RWA damage. Prior to sampling plots, multi-spectral imagery was obtained using an SSTCRIS® multi-spectral imaging system mounted NADIR in a Cessna 172 aircraft. The multi-spectral data were used to compare with RWA infestation level for each plot. Correlations between vegetation indices and the proportion of RWA damaged wheat tillers per plot were negative for all vegetation indices calculated.
    [Show full text]