DOCSLIB.ORG

1 Suction Trapping of Selected Small Grain Aphids in Colorado, 1988-1998 Robert W. Hammon1, Terri L. Randolph2, J. Scott Armstro

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
1 Suction Trapping of Selected Small Grain Aphids in Colorado, 1988-1998 Robert W. Hammon1, Terri L. Randolph2, J. Scott Armstro Suction Trapping of Selected Small Grain Aphids in Colorado, 1988-1998 Robert W. Hammon1, Terri L. Randolph2, J. Scott Armstrong3, Cynthia B. Walker4, Jeffrey B. Rudolph2, Michael D. Koch5, Wendy L. Meyer6, and Frank B. Peairs2 1 Fruita Research Center, 1910 L Rd., Fruita, CO 81521 2 Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins CO 80523 3Plant and Soil Science, Texas Tech University, Lubbock TX 79409 4Colorado State University, 1001 S. Main, Lamar CO 81052 5 USDA Central Great Plains Research Station, P.O. Box 400, Akron CO 80720 6TREC, 18905 SW 280th St., Homestead FL 33031 1 Aphids are serious pests of small grains climactic conditions. Eggs are much less worldwide because of direct feeding damage and vulnerable to climactic extremes than living the ability to transmit plant pathogens. In aphids, so Russian wheat aphid populations are Colorado, the major cereal aphid pests are the more stable from year to year in areas where Russian wheat aphid, Diuraphis noxia there is no sexual reproduction. Males have never (Mordvilko), greenbug, Schizaphis graminum been found in North America so all reproduction (Rodani), and bird-cherry oat aphid, is assumed to be asexual. Russian wheat aphids Rhopalosiphum padi (L.). The Russian wheat spend the winter as living aphids, feeding on host aphid, introduced into the United States in 1986, plants when climactic conditions permit causes chlorotic leaf streaking, leaf stunting and (Hammon and Peairs, 1992). When winters are rolling, and trapped and distorted heads. Losses very cold or there is extended snow cover, to Russian wheat aphid have exceeded $112 Russian wheat aphid populations decrease or million in damage in Colorado (F.B. Peairs, winter kill (Armstrong and Peairs 1996, Butts unpublished) and $500 million in the USA since and Schaalje 1997). Winter mortality can occur its introduction (Morrison and Peairs, 1998). The over a large region or only within isolated greenbug and bird cherry-oat aphid cause portions of an area. When winter mortality of considerable direct damage to plant growth and aphids occurs over a large area, the region can be yield in both winter wheat and barley (Kieckhefer reinfested by flights of alatae (winged aphids) & Kantack, 1988, Ortman and Painter 1960, from another area. Russian wheat aphid Mallott and Davy 1978) and spring wheat and populations increase in the spring as they barley (Kieckhefer & Kantack 1980, Voss et. al. reproduce on wheat and barley. Local movement 1997). They are also vectors of barley yellow occurs as these aphids move within and between dwarf virus (Gildow 1984, Blackman et al. fields. This is evident in areas where spring 1987), which also causes significant damage to grains are produced, as these fields may be the world’s small grain crops (Burnett 1990). infested by alatae soon after plants emerge. As The three aphid species discussed in this the grain crop matures, many alatae are produced publication have different life histories which which migrate to oversummering host plants. Fall explain, in part, the varying patterns of suction migration occurs as aphids migrate from trap captures. oversummering host plants into the newly Russian wheat aphids feed only on emerged fall planted small grain crop. grasses, with cool season grasses that are Bird cherry-oat aphids have a variety of botanically related to wheat being preferred hosts life cycle phenotypes. Some have an obligate (Hammon et. al.1997, Kindler and Springer heteroecious (host-alternating) holocyclic (with a 1989). In eastern Europe and Asia, Russian sexual stage) life history, while others are mostly wheat aphids reproduce asexually during the holocyclic with a residual anholocyclic (asexual) spring and summer, followed by a sexual population. Some clones are permanently generation in the fall. They overwinter either as anholocyclic. In the heteroecious forms, alate eggs or living aphids, depending on local aphids migrate to chokecherry plants in the fall, 2 where overwintering eggs are produced. Eggs are capture alate aphids (Allison and Pike, 1988) laid after mating of the oviparae (egg producing which are weak flying insects responsible for females) with migrant males. Eggs are more dispersal. Alatae are formed in response to resistant to cold and dessication than living various factors, such as overcrowding and aphids. The eggs hatch in the spring. These decline in host plant suitability. The number of aphids reproduce asexually, and after one or alatae present is determined by the total number more generations on chokecherry, alatae are of aphids, growth stage of host plants, season, produced that migrate to wheat or other grasses, and other factors. Some species, such as bird where many generations of both alatae and cherry-oat aphid produce many alatae to move to apterae (wingless aphids) are produced during overwintering hosts, resulting in late season the summer. In the late summer, many bird peaks in aphid captures. Other species, such as cherry-oat aphids infest corn and other grassy Russian wheat aphid, always have a few alatae hosts, where they sometimes become abundant. present with the proportion of the population in Anholocyclic populations of bird cherry-oat the alate form increasing in response to aphids on wheat may survive the winter, feeding environmental stresses and crop maturity. near the base of plants and reproducing asexually In Europe, suction traps are used to if environmental conditions are not too severe. monitor movement of many aphid species, and to Greenbug also has a holocyclic life predict outbreaks resulting from immigrating history in parts of their range, but sexual forms aphids (Turl 1980, Dewar et al 1984). In South are rare in Colorado. The life history of Dakota, Kieckhefer et al. (1974) used suction holocyclic greenbug populations differ from that trap data to show aphid immigration was of bird cherry-oat aphid in that the egg stage is associated with low-level jet winds. Loxdale et al. spent on the same grass species that the asexual (1993) reviewed the evidence concerning short summer and fall generations feed on (monoecious and long-range movement of aphids, and holocyclic). Their life history is similar to that of concluded that while long-range movement of Russian wheat aphid in that only grasses are used aphids (>100 km) certainly occurs, it is as host plants. The host range of greenbug is infrequent. Short-range dispersal (<20 km) is different than that of Russian wheat aphid, as it much more important in the population dynamics is a serious pest of warm season grasses such as of aphid outbreaks. Halbert et al. (1998) corn, sorghum and millet in addition to wheat. presented evidence that suction trap captures Greenbugs may survive the winter by feeding on reflect aphid flight activity within a 30 km radius host plants and reproducing asexually if of the trap. Halbert and Voegtlin (1994) used the environmental conditions are not too severe. capture of host specific aphids to predict the Monitoring of aphid populations is presence of purple loosestrife, a noxious weed. important to document the extent and severity of Halbert et al. (1995) used the aphid species infestations in a particular area and aid in assemblage collected in suction traps as an predicting future infestations. Suction traps have indicator of plant biodiversity in an area. been used to monitor and forecast peak In 1983 the Western regional suction migrations of various aphids. Suction traps trapping system began to monitor barley yellow 3 dwarf virus vector activity in the Pacific Northwest (Pike et al. 1987, Allison and Pike • Akron - USDA Central Great Plains 1988, Quinn et al. 1991). This system now Research Center, 4 mi E of Akron, monitors Russian wheat aphid flight patterns to Washington Co. alert growers of Russian wheat aphid • Fort Collins - 7 mi S of Briggsdale infestations. The earliest yearly collections of (1988-1993), Weld Co.; ARDEC (1994- Russian wheat aphid have generally coincided 1998), 5 mi S of Wellington, Larimer with detectable populations in spring seeded Co. cereal crops, and have occurred before economic • Fruita - Fruita Research Center, 2 mi NE thresholds have been exceeded. Fall collections of of Fruita, Mesa Co. Russian wheat aphids have indicated that they • Walsh - Plainsman Research Center, 0.5 have successfully oversummered, and there was a mi W of Walsh, Baca Co.. potential for infestation of the fall seeded cereal • Yellow Jacket - Southwestern Colorado crop (Halbert et al. 1998). A network of suction Research Center, 1 mi N of Yellow traps was set up in small grain producing regions Jacket, Montezuma Co. of Colorado in 1988 to monitor populations of Russian wheat aphid and other small grain The traps were changed weekly at a aphids. This publication presents the results of minimum. Heavy rains, power outages and this trapping at certain locations for the period of mechanical failures have caused short term 1988-1998. It gives an important historical disruptions in data collection at all sites. Single perspective on small grain aphid abundance and missing data points were estimated by averaging movement during that time period. the two data points surrounding the missing data. If more than two consecutive weeks were METHODS AND MATERIALS missing, the points were not graphed. The data are presented in Figures 4-18 as weekly captures. Suction traps constructed to the Data points greater than zero are plotted with dot specifications of Allison and Pike (1988) were symbols. If no symbol is present, the capture was placed in the field in the spring of 1988. The either zero or missing. If there is no line traps are 28 ft tall, with an opening diameter of connecting two points, there are missing data 12 in. An electric fan pulls air through the traps points. and insects are funneled into a jar containing a Temperature and precipitation data was 50:50 mixture of ethylene glycol and 95% obtained from the Colorado Climate Center ethanol, which kills and preserves the catch.
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]
  • 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]
  • 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]
  • 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]
  • The Russian Wheat Aphid in Utah
    Extension Entomology Department of Biology, Logan, UT 84322 Utah State University Extension Fact Sheet No. 80 February 1993 THE RUSSIAN WHEAT APHID IN UTAH Introduction Since arriving in Utah in 1987, the Russian wheat aphid, Diuraphis noxia (Kurdjumov), has spread to all grain growing areas of the state. It is very unpredictable in that at times it becomes an economic pest and at other times it is just present. In some areas it has caused losses in wheat and barley of up to 50 percent or more. It can be a problem in fall or spring planted grains. Biology Russian wheat aphids infest wheat, barley, and triticale, as well as several wild and cultivated grasses. Broadleaf plants such as alfalfa, clover, potatoes, and sunflowers are not hosts. Volunteer grain plays a key role in the life cycle of this pest by providing a food source in the interval between grain harvest and the emergence of fall-seeded crops. Many species of grasses act as reservoir hosts during the late-summer dry season; however, grasses such as barnyard grass and foxtail grass that grow on irrigation ditch banks and other wet waste areas are poor hosts. Most wild desert grasses are normally dormant and unsuitable for aphids during this period. In some cases, winged forms may feed on corn during heavy flights, but no colonization occurs. In the summer, all Russian wheat aphids are females that do not lay eggs but give birth to live young at a rate of four to five per day for up to four weeks. The new young females can mature in as little as 7-10 days.
    [Show 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,
    [Show full text]
  • Russian Wheat Aphid: Natural Enemies, Resistant Wheat Offer Potential Control Rz D
    Russian wheat aphid: natural enemies, resistant wheat offer potential control rz D. Gonzalez a Charles G. Summers o Calvin 0. Qualset u> 2 f Adult Russian wheat aphid. wears. Coordinated research to de- and social costs or the concerns associated velop economically and environ- with COmba~gRwA tati ions with insecticides. At present, insecticides are management the only RWA control tactic available to strategies for this pest is in California farmers. Continued use of these progress. agents will destroy native natural enemies, accelerate dev~opm~tof insecticide re- In March 1986, Russian wheat aphid sistance in RWA and other insect pests, (RWA),Diuruphis noxiu (Mordvilko),was and upset se~ndarypests. The results, first reported present in the United States, short-term, are induced pest outbreaks. causing crop losses in small grains in The results, long-term, are cont~ation Texas. Since then, it has spread, infesting of soil and watert wildlife losses, and gen- View of aphid from above showing characteris- small grains in Oklahoma, Kansas, Ne- eral en~o~ent~degradation. Economi- tic short antennae, double tail, and very short braska and South Dakota and moving cdy, too, the extensive acreage planted cornicles (small tubelike projections on each west to California, Oregon and Washing- with small gains, depressed markets and side of the aphid). ton. Crop losses in 1988 were an estimated decreased prices make unilateral chemical $130 million, 2.4 times greater than in protection a poor option. 1987. Losses since 1986 have exceeded ~u~he~ore,~~ea~edsmall grains $500 million. nonnally host native natural enemiesf pro- Russian wheat aphid is a small, pale viding natural control of potential p~ma~ green insect, often covered with a white and second^ pests in their crops and in powdery coating of wax.
    [Show full text]
  • (Aegilops Cylindrica Host.) in Winter Wheat
    Utah State University DigitalCommons@USU All Graduate Theses and Dissertations Graduate Studies 5-1996 An Integration of Tillage and Herbicides to Control Jointed Goatgrass (Aegilops Cylindrica Host.) in Winter Wheat Troy M. Price Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/etd Part of the Plant Sciences Commons Recommended Citation Price, Troy M., "An Integration of Tillage and Herbicides to Control Jointed Goatgrass (Aegilops Cylindrica Host.) in Winter Wheat" (1996). All Graduate Theses and Dissertations. 4602. https://digitalcommons.usu.edu/etd/4602 This Thesis is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Theses and Dissertations by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. AN INTEGRATION OF TILLAGE AND HERBICIDES TO CONTROL JOINTED GOATGRASS (AEGILOPS CYLINDRICA HOST.) IN WINTER WHEAT by Troy M . Price f. thesis submitted in partial fu!fi!lrr.er:t of the requirements for the degree of MASTER OF SCIENCE in Plant Science UTAH STATE UNIVERSITY Logan, Utah 1996 ii ABSTRACT An Integration of Tillage and Herbicides to Control Jointed Goatgrass (Aegilops cylindrica Host.) in Winter Wheat by Troy M. Price, Master of Science Utah State University, 1996 Major Professor: Dr. John 0. Evans Department: Plants, Soils and Biometeorology An integrated management approach for jointed goatgrass control was investigated at two farms in northern Utah using three tillage regimes and three herbicides. The tillage regimes included no tillage, conservation tillage, and conventional tillage. Each regime was composed of different tillage practices common in the Intermountain West.
    [Show full text]
  • Effects of Plant Viruses on Vectors and Non-Vector Herbivores in Three
    Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School March 2019 Effects of Plant Viruses on Vectors and Non-vector Herbivores in Three Different Pathosystems Sunil Paudel Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Entomology Commons Recommended Citation Paudel, Sunil, "Effects of Plant Viruses on Vectors and Non-vector Herbivores in Three Different Pathosystems" (2019). LSU Doctoral Dissertations. 4870. https://digitalcommons.lsu.edu/gradschool_dissertations/4870 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. EFFECTS OF PLANT VIRUSES ON VECTORS AND NON-VECTOR HERBIVORES IN THREE DIFFERENT PATHOSYSTEMS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Entomology by Sunil Paudel B. S., Tribhuvan University, 2008 M.S., University of Idaho, 2013 May 2019 ACKNOWLEDGEMENTS I would like to express my sincere gratitude to my major advisor, Dr. Jeffrey A. Davis for his continuous support throughout my graduate studies, for his patience, encouragement, and guidance that helped me to grow as a researcher and a critical thinker. I am also thankful to my dissertation committee members, Drs. Michael J. Stout, Fangneng Huang, Jeffrey W. Hoy, and Dean’s representative Dr.
    [Show full text]
  • Field Resistance in Bread Wheat to Russian Wheat Aphid, Diuraphis Noxia Under Flood Irrigation
    Ethiop. J. Agric. Sci. 28(2) 85-98 (2018) Field Resistance in Bread Wheat to Russian Wheat Aphid, Diuraphis noxia Under Flood Irrigation Tebkew Damte and Geteneh Mitiku Ethiopian Institute of Agricultural Research, Debre Zeit Center, P. O. Box 32, Debre Zeit, Ethiopia አህፅሮት የሩሲያ ክሽክሽ (Diuraphis noxia) በዓሇም ሊይ በሰፊው የተሰራጨ ተባይ ሲሆን የስንዴ ምርትን እስከ 93 በመቶ ሉያወድም ይችሊል፡፡ እንዲሁም ይህ ክሽክሽ ቅዉም ሰባሪዎች ስሊሇው ክሽክሹን የሚቋቋሙ ዝርያዎች የሚያገሇግለት ሇተወሰነ አካባቢ ብቻ ነው፡፡ ይህም በመሆኑ ከኢትዮጵያ ውጭ ባለ ስንዴ አብቃይ አገሮች ክሽክሹን የሚቋቋሙ 49 ብዝሀ-ዘሮችን በማስገባት ዯብረ ዘይት ሊይ ሇሁሇት ዓመት (2007 እና 2008 ዓም) መስኖ እና የተፈጥሮ ወረራ በመጠቀም ተፈትሿል፡፡ ሙከራው የተካሄዯው 7 በ 7 በሆነ የሊቲስ ንድፍ ሊይ ብዝሀ-ዘሮችን በመዝራት ነው፡፡ ሙከራ ከተዯረገባቸው 49 ብዝሀ-ዘሮች መካከል ከሩሲያ ክሽክሽ ወረራ ነፃ የሆነ ብዝሀዘር ባይኖርም በክሽክሽ አህዛብ ብዛት ግን ሰፊ ተሇያይነት ነበር፡፡ በሁሇቱም ዓመት ከፍተኛ ቁጥር ባሇው ክሽክሽ የተወረሩና ከፍተኛ ጥቃት የዯረሰባቸው ብዝሀ-ዘሮች ትንሽ ቁጥር ባሇው ክሽክሽ የተወረሩ እና ከፍተኛ ቅውሞሽ ያሳዩ ብዝሀ-ዘሮች ነበሩ፡፡ ቀሪዎች ብዝሀ-ዘሮች ግን መካከሇኛ የቅውሞሽ ዯረጃ ነበራቸው፡፡ ስሇሆነም የሩሲያ ክሽክሽ አህዛብ ዕድገት በተሇያዩ ብዝሀ-ዘሮች የተሇያየ ነበር፡፡ በተጨማሪም በተወረሩ ቀዘባዎች (መቶኛ) እና በአንድ ቀዘባ ሊይ የነበረው የክሽክሽ ብዛት መካከል ቀጥተኛ ግንኙነት አልነበረም፡፡ Abstract The Russian wheat aphid (RWA) (Diuraphis noxia) is cosmopolitan pest and yield losses of up to 93% have been reported in different wheat growing countries. It also has a high degree of biotypic diversity that necessitates the development and utilization of location specific resistant wheat varieties. Thus, 49 wheat genotypes known to be resistant to RWA in other countries were evaluated using natural infestation in 7x7 Simple Lattice for two seasons under flood irrigation at Debre Zeit, Ethiopia.
    [Show full text]
  • Natural Enemies of Russian Wheat Aphid Identified in California
    California cereal crops have suffered massive damage from Russian wheat aphid since 1988. Natural enemies of Russian wheat aphid identified in California J. Bernal o D. Gonzalez o E.T. Natwick o J.G. Loya o R. Leon-Lopez o W. E. Bendixen A survey of natural enemies of Since its detection in Texas in 1986, Recommendations for managing the Russian wheat aphid conducted Russian wheat aphid [Diuraphisnoxia aphid, largely adopted from other (Mordwilko)]has become a major pest countries where the pest is present, rely over several growing seasons re- of small grains in 16 western states and heavily on insecticide use. Management veals a complex of predators and has caused losses cumulatively exceed- strategies being developed in California parasites attacking this pest in ing $500 million. First detected in Cali- involve biological control and crop resis- California cereal fields. Because fornia’s Imperial County in 1988, the tance because unilateral use of insecti- aphid did an estimated $8 million of cides may not be economically, biologi- of environmental and economic damage to the state’s cereal crops in the cally or ecologically sound. Furthermore, considerations, unilateral use of 1988-1989 growing season. extensive planting to small grains, with insecticides is not a sound man- The Russian wheat aphid was first re- depressed market prices, makes chemi- agement strategy against this corded during the early 1900s as a pest cal control too costly. The continued of cereals in areas along the Black Sea’s spread of this pest into new areas pre- pest. A number of promising natu- northern coast (former USSR).
    [Show full text]