Evaluation and Mechanisms of Host-Plant Resistance to The

Total Page:16

File Type:pdf, Size:1020Kb

Evaluation and Mechanisms of Host-Plant Resistance to The Mississippi State University Scholars Junction Theses and Dissertations Theses and Dissertations 8-6-2021 Evaluation and mechanisms of host-plant resistance to the wireworm-Diabrotica-Systena complex in sweetpotatoes (Ipomoea batatas) and a commercial kairomone lure in Diabroticites Thomas J. Douglas [email protected] Follow this and additional works at: https://scholarsjunction.msstate.edu/td Recommended Citation Douglas, Thomas J., "Evaluation and mechanisms of host-plant resistance to the wireworm-Diabrotica- Systena complex in sweetpotatoes (Ipomoea batatas) and a commercial kairomone lure in Diabroticites" (2021). Theses and Dissertations. 5282. https://scholarsjunction.msstate.edu/td/5282 This Graduate Thesis - Open Access is brought to you for free and open access by the Theses and Dissertations at Scholars Junction. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholars Junction. For more information, please contact [email protected]. Template B v4.3 (beta): Created by T. Robinson 01/2021 Evaluation and mechanisms of host-plant resistance to the wireworm-Diabrotica-Systena complex in sweetpotatoes (Ipomoea batatas) and a commercial kairomone lure in Diabroticites By TITLE PAGE Thomas J. Douglas Approved by: Fred Musser (Major Professor) Ashli Brown-Johnson Blake M. Layton Stephen L. Meyers Natraj Krishnan (Graduate Coordinator) Scott T. Willard (Dean, College of Agriculture and Life Sciences) A Thesis Submitted to the Faculty of Mississippi State University in Partial Fulfillment of the Requirements for the Degree of Master of Science in Agricultural Life Sciences in the Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology Mississippi State, Mississippi August 2021 Copyright by COPYRIGHT PAGE Thomas J. Douglas 2021 Name: Thomas J. Douglas ABSTRACT Date of Degree: August 6, 2021 Institution: Mississippi State University Major Field: Agricultural Life Sciences Major Professor: Fred Musser Title of Study: Evaluation and mechanisms of host-plant resistance to the wireworm-Diabrotica- Systena complex in sweetpotatoes (Ipomoea batatas) and a commercial kairomone lure in Diabroticites Pages in Study: 54 Candidate for Degree of Master of Science An evaluation of host-plant resistance to the wireworm-Diabrotica-Systena (WDS) complex of root-feeding insects in sweetpotatoes was performed on a total of 15 cultivars and advanced lines over the course of 4 years (2017-2020). It was found that sweetpotatoes varieties can differ significantly in amount of damage incurred. Several mechanisms of resistance were proposed and tested: periderm toughness, dry weight percentage, and volatile organic chemical defenses. No significant difference was found amongst the varieties tested concerning the physical properties. Chemical analysis was limited in scope but did show some differences between a susceptible variety when compared to a resistant variety in the volatile chemical composition of the foliage. Finally, a commercial kairomone lure with sticky card for Diabroticites was tested for efficacy when compared to sweep net sampling throughout the season. No correlation could be found amongst the methods in terms of number and species of insects caught by each. ACKNOWLEDGEMENTS I would like to thank USDA-ARS for funding for this research and providing slips for advanced lines from their breeding program as well as LSU AgCenter and NC State. I would also like to express my gratitude to my advisor, Dr. Fred Musser, for his guidance over the course of the last two and a half years. I would like to thank the other members of my committee: Dr. Blake Layton, Dr. Ashli Brown, and Dr. Stephen Meyers for their assistance in providing feedback on my research ideas and on this thesis. This research would not have been possible without the assistance from the other members of the lab who helped with planting and harvesting: Beverly Catchot, Lauren Sanders, Farrar Misso, Shannon Oswald, Coty Martin, Chance Anderson, and Blaye Brasher. I would like to thank Jessi Collier and other members of the Hand chemistry lab for their assistance with the gas chromotagraphy and mass spectrometry analysis. Thank you to the faculty and staff of the Pontotoc Ridge-Flatwoods Branch Experiment Station for their hard work in replicating the research at their facility and providing slips each year from their plant beds. I am also grateful to Earp Farms, Topashaw Farms, and Ellison Farms for allowing me to put lures out in their fields. Last, but not least, I want to thank my family for their unwavering support during this whole process. iii TABLE OF CONTENTS ACKNOWLEDGEMENTS ........................................................................................................... iii LIST OF TABLES ...........................................................................................................................v LIST OF FIGURES ....................................................................................................................... vi CHAPTER I. INTRODUCTION .............................................................................................................1 Introduction .......................................................................................................................1 Insect Pests of Sweetpotatoes ......................................................................................2 Control of the WDS Complex .....................................................................................6 References .........................................................................................................................8 II. RESISTANCE TO THE WIREWORM-DIABROTICA-SYSTENA COMPLEX IN SWEETPOTATO (IPOMOEA BATATAS) CULTIVARS AND ADVANCED LINES .........................................................................................................................................10 Abstract ............................................................................................................................10 Introduction .....................................................................................................................10 Materials and Methods ....................................................................................................12 Results .............................................................................................................................13 Discussion ........................................................................................................................13 References .......................................................................................................................19 III. PHYSICAL AND CHEMICAL MECHANISMS OF RESISTANCE TO THE WIREWORM-DIABROTICA-SYSTENA COMPLEX IN SWEETPOTATO .............21 Introduction .....................................................................................................................21 Materials and Methods ....................................................................................................23 Results and Discussion ....................................................................................................25 References .......................................................................................................................30 IV. EFFICACY OF KAIROMONE TRAPS FOR CUCUMBER BEETLES IN SWEETPOTATOES .......................................................................................................33 Abstract ............................................................................................................................33 Introduction .....................................................................................................................33 Materials and Methods ....................................................................................................35 Results and Discussion ....................................................................................................36 References .......................................................................................................................42 iv LIST OF TABLES Table 2.1 Cultivars and advanced lines included at each trial site-year .....................................15 Table 2.2 Site-year agronomic details including replications, planting date, and information pertinent to that site-year ........................................................................16 Table 3.1 A list of Volatile Organic Compounds (VOCs) that could play a role in insect resistance identified in the sweetpotatoes tissues tested using Gas Chromotagraphy and Mass Spectrometry ..................................................................27 Table 4.1 Summary of Trap Catches by Sticky Cards\Kairomone Lure and Sweeps ................39 Table A.1 List of VOC’s Identified in Plant Defense .................................................................45 v LIST OF FIGURES Figure 2.1 Mean percent marketable yield (±SEM) of each line when compared to Beauregard; 2017-2020. Any values less than 100 yielded less than Beauregard, any values higher than 100 yielded more than Beauregard (SAS 9.4). .............................................................................................................................17 Figure 2.2 Mean WDS holes (±SEM) per potato by line; 2017-2020. Higher values indicate an increased susceptibility to WDS damage. Large standard error bars are a
Recommended publications
  • Insect Management
    C H A P T E R 5 INSECT MANAGEMENT “change in form.” Pests of field crops undergo either sim- LEARNING OBJECTIVES ple or complete metamorphosis. After completely studying this chapter, you should: Group 1. Simple Metamorphosis I Understand how insects grow and develop. When insects that develop by simple metamorphosis hatch from their eggs, they resemble the adult insects I Understand the difference between simple and com- except that the immatures, or nymphs, do not have plete metamorphosis. wings. Nymphs periodically molt, growing larger. After I Be able to identify general and major insect pests of the final molt, nymphs become adults and generally have alfalfa, corn, dry beans, soybeans, small grains, and wings. Many pests of field crops such as potato leafhop- sugar beets. per, sugarbeet root aphid, tarnished plant bug, and grasshoppers develop by simple metamorphosis. I Be able to describe the life cycles and habitats of the Nymphs and adults are often found together in the crop major field crop pests. and usually eat the same food. Insect damage reduces crop yield or quality, or conta- minates the final product. Insects can also transmit plant diseases. To effectively control insect pests, you should understand how insects grow and develop. Egg Nymphs Adult GROWTH AND DEVELOPMENT A plant bug is an example of an insect with simple Growth metamorphosis. An insect’s body is confined in a protective exoskele- Group 2. Complete Metamorphosis ton. This hard outer covering does not grow continuous- ly. A new, soft exoskeleton is formed under the old one, Insects that develop by complete metamorphosis and the old exoskeleton is shed—a process called molt- make a radical change in appearance from immature to ing.
    [Show full text]
  • Organic Options for Striped Cucumber Beetle Management in Cucumbers Katie Brandt Grand Valley State University
    Grand Valley State University ScholarWorks@GVSU Masters Theses Graduate Research and Creative Practice 6-2012 Organic Options for Striped Cucumber Beetle Management in Cucumbers Katie Brandt Grand Valley State University Follow this and additional works at: http://scholarworks.gvsu.edu/theses Recommended Citation Brandt, Katie, "Organic Options for Striped Cucumber Beetle Management in Cucumbers" (2012). Masters Theses. 29. http://scholarworks.gvsu.edu/theses/29 This Thesis is brought to you for free and open access by the Graduate Research and Creative Practice at ScholarWorks@GVSU. It has been accepted for inclusion in Masters Theses by an authorized administrator of ScholarWorks@GVSU. For more information, please contact [email protected]. ORGANIC OPTIONS FOR STRIPED CUCUMBER BEETLE MANAGEMENT IN CUCUMBERS Katie Brandt A thesis Submitted to the Graduate Faculty of GRAND VALLEY STATE UNIVERSITY In Partial Fulfillment of the Requirements For the Degree of Master of Science Biology June 2012 2 ACKNOWLEDGEMENTS Many thanks to my advisors, who helped me plan this research and understand the interactions of beetles, plants and disease in this system. Jim Dunn helped immensely with the experimental design and prevented me from giving up when my replication block was destroyed in a flood. Mathieu Ngouajio generously shared his expertise with organic vegetables, field trials and striped cucumber beetles. Mel Northup lent the HOBO weather stations, visited the farm to instruct me to set them up and later transferred the data into an Excel spreadsheet. Sango Otieno and the students at the Statistical Consulting Center at GVSU were very helpful with data analysis. Numerous farmworkers and volunteers also helped in the labor-intensive process of gathering data for this research.
    [Show full text]
  • Chrysomela 43.10-8-04
    CHRYSOMELA newsletter Dedicated to information about the Chrysomelidae Report No. 43.2 July 2004 INSIDE THIS ISSUE Fabreries in Fabreland 2- Editor’s Page St. Leon, France 2- In Memoriam—RP 3- In Memoriam—JAW 5- Remembering John Wilcox Statue of 6- Defensive Strategies of two J. H. Fabre Cassidine Larvae. in the garden 7- New Zealand Chrysomelidae of the Fabre 9- Collecting in Sholas Forests Museum, St. 10- Fun With Flea Beetle Feces Leons, France 11- Whither South African Cassidinae Research? 12- Indian Cassidinae Revisited 14- Neochlamisus—Cryptic Speciation? 16- In Memoriam—JGE 16- 17- Fabreries in Fabreland 18- The Duckett Update 18- Chrysomelidists at ESA: 2003 & 2004 Meetings 19- Recent Chrysomelid Literature 21- Email Address List 23- ICE—Phytophaga Symposium 23- Chrysomela Questionnaire See Story page 17 Research Activities and Interests Johan Stenberg (Umeå Univer- Duane McKenna (Harvard Univer- Eduard Petitpierre (Palma de sity, Sweden) Currently working on sity, USA) Currently studying phyloge- Mallorca, Spain) Interested in the cy- coevolutionary interactions between ny, ecological specialization, population togenetics, cytotaxonomy and chromo- the monophagous leaf beetles, Altica structure, and speciation in the genus somal evolution of Palearctic leaf beetles engstroemi and Galerucella tenella, and Cephaloleia. Needs Arescini and especially of chrysomelines. Would like their common host plant Filipendula Cephaloleini in ethanol, especially from to borrow or exchange specimens from ulmaria (meadow sweet) in a Swedish N. Central America and S. America. Western Palearctic areas. Archipelago. Amanda Evans (Harvard University, Maria Lourdes Chamorro-Lacayo Stefano Zoia (Milan, Italy) Inter- USA) Currently working on a phylogeny (University of Minnesota, USA) Cur- ested in Old World Eumolpinae and of Leptinotarsa to study host use evolu- rently a graduate student working on Mediterranean Chrysomelidae (except tion.
    [Show full text]
  • WESTERN SPOTTED CUCUMBER BEETLE Coleoptera: Chrysomelidae Diabrotica Undecimpunctata Undecimpunctata ______DESCRIPTION
    Modified from Ralph E. Berry. 1998©. Insects and Mites of Economic Importance in the Northwest. 2nd Ed. 221 p. WESTERN SPOTTED CUCUMBER BEETLE Coleoptera: Chrysomelidae Diabrotica undecimpunctata undecimpunctata ___________________________________________________________________________ DESCRIPTION Adults are 6 mm long, yellowish-green with distinct black spots on the wing covers. This species is a subspecies of the southern corn rootworm, D. undicimpunctata howardi, which is a serious pest of corn in the central United States. Mature larvae of the western spotted cucumber beetle are 14 to 17 mm long. They are white, except the head and last abdominal segment, which are brown. ECONOMIC IMPORTANCE Larvae of this pest feed on roots of potatoes, corn, Adult snap beans, immature cole crops, and some other vegetables. On potatoes, feeding injury resembles damage caused by flea beetle larvae. Adults feed on corn silk, pollen, bean leaves, blossoms and developing pods, and pollen of cucurbits. This damage causes inadequate pollination resulting in reduced yields, poor seed set, and considerable wastage in beans at processing plants. Processors dock growers and downgrade quality if the damage from cucumber beetle adults exceeds the equivalent of 1.5 scars ("beetle bites") per 100 pods. Larva DISTRIBUTION AND LIFE HISTORY This species occurs throughout western Oregon and W. SPOTTED CUCUMBER BEETLE Washington. This insect overwinters as a fertilized ADULTS female. Adults are active during mild periods in the EGGS EGGS winter, but do not begin laying eggs until early LARVAE LARVAE spring. Eggs are deposited in the soil around the PUPAE PUPAE bases of host plants. Eggs hatch in seven to 10 days ADULTS ADULTS and larvae feed on roots for about three weeks before J F M A M J J A S O N D pupating in the soil.
    [Show full text]
  • CERTAIN INSECT VECTORS of APLANOBACTER STEWARTI ' by F
    CERTAIN INSECT VECTORS OF APLANOBACTER STEWARTI ' By F. W. Poos, senior entomologist, Division of Cereal and Forage Insects, Bureau of Entomology and Plant Quarantine; and CHARLOTTE ELLIOTT, associate pa- thologist, Division of Cereal Crops and Diseases, Bureau of Plant Industry, United States Department of Agriculture ^ INTRODUCTION Bacterial wilt of corn (Zea mays L.) caused by Aplanobacter stewarti (E. F. Sm.) McC. was exceedingly destructive and more widely dis- tributed during 1932 and 1933 than during any previous time in the history of the disease. Since 1897, when it was first described by Stewart, it has been studied by a number of investigators whose work has pointed more and more toward insects as a means of dis- semination of the causal organism. Kand and Cash (7) ^ during 1920-23 found that bacterial wilt could be transmitted from diseased to healthy com plants by two species of flea beetles, Chaetocnema pulicaria Melsh. and C, denticulata (111.), and by the spotted cucum- ber beetle, Diabrotica duodecimpunctata (Fab.). IvanoíF (ö) reported transmission from diseased to healthy plants by the larval stage of the corn rootworm, Diabrotica longicornis (Say), as it attacked the roots of young seedling com plants. He also reported that the bac- teria of A. stewarti entered the corn plants through wounds made by white grubs, the larvae of Phyllophaga sp., feeding upon the roots in infested soil. A summary of this work, together with a brief review of the other literature on this disease, has recently appeared else- where (1), The results of experiments by previous investigators on soil trans- mission of the causal organism indicate that transmission through the soil to uninjured roots of com plants is exceedingly rare, if it ever occurs.
    [Show full text]
  • Article-P605.Pdf
    J. AMER. SOC. HORT. SCI. 118(5):605-608. 1993. Potential of Non-chemical Control Strategies for Reduction of Soil Insect Damage in Sweetpotato J.M. Schalk1, J.R. Bohac2, and P.D. Dukes3 U.S. Department of Agriculture, Agricultural Research Service, U.S. Vegetable Laboratory, 2875 Savannah Highway, Charleston, SC 29414 W.R. Martin4 Biosys, 1057 East Meadow Circle, Palo Alto, CA 94303 Additional index words. Ipomoea batatas, parasitic nematode, plant resistance, biological control, wireworms, flea beetles, grubs, cucumber beetles Abstract. This 2-year study was conducted to determine if soil insect damage could be reduced in sweetpotato [Ipomoea batatas (L.) Lam] by treatment with an insecticide (fonofos) and/or a parasitic nematode (Steinernema carpocapsae Weiser), in conjunction with sweetpotato cultivars that differed in susceptibility to soil insect damage. Analysis of field data for the first year showed that the parasitic nematode provided significant damage protection of sweetpotato from wireworms (Conoderus spp.), Diabrotica sp., Systena sp., and sweetpotato flea beetle (Chaetocnema confinis Crotch), but not from grubs (Plectris aliena Chapin; Phyllophaga ephilida Say). In this same test, fonofos used alone provided protection against wireworm- Diabrotica-Systena (WDS complex) damage. In the second test, the nematode did not provide soil insect protection for the WDS complex, but fonofos did reduce damage for these insects. Poor efficacy in the second test with the nematode probably was due to high rainfall, which saturated the soil. Resistant cultivars provided good protection for all three categories of damage. When used with the insect-susceptible check ‘SC 1149-19’, the nematode or fonofos treatments provided better control for all insect categories in the first test.
    [Show full text]
  • Redheaded Flea Beetle Integrated Pest Management Andrew Kness and Brian A
    Redheaded Flea Beetle Integrated Pest Management Andrew Kness and Brian A. Kunkel, University of Delaware, Department of Entomology & Wildlife Ecology, Newark, DE ABSTRACT: Redheaded flea beetle (Systena frontalis) has become a serious pest insect of woody and herbaceous ornamental plants over the last several years. Our research focused on identifying when key life stages of the redheaded flea beetle were active and correlating these stages with growing degree day (GDD) data and plant phonological indicators (PPIs). Choice and no-choice feeding assays were conducted to determine host plant preferences. Entomopathogenic nematodes (epns) were applied to containers in field experiments at two locations to evaluate efficacy against the soil-dwelling larvae. Overwintering eggs hatch with larvae active between 257– 481 GDD50, and the corresponding PPIs were black locust and Chinese fringetree in full bloom. First adult emergence occurred between 590– 785 GDD50, and the PPIs were Magnolia grandiflora in flower bud swell to bloom. The second generation of larvae was found between 1818– 1860 GDD50 and the following plants were in the indicated phenological stage: 1) Hosta in full bloom, 2) Crape Myrtle ‘Hopi Pink’ bloom to full bloom, 3) Crape Myrtle ‘Siren Red’ flower bud swell, 4) Hibisucs in bloom and 5) Cerastigma plumbaginoides in bloom. Field observations and choice tests found S. frontalis feeds on many different hosts and exhibited little preference between host plants tested. Field trials with epns did not provide significant control of S. frontalis larvae in either experiment. Further work with potting media, soil temperatures and irrigation needs to continue in order to improve EPN efficacy.
    [Show full text]
  • Disease and Insect Pest Management in Organic Cucurbit Production Hayley Nelson Iowa State University
    Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2019 Disease and insect pest management in organic cucurbit production Hayley Nelson Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Agriculture Commons, and the Plant Pathology Commons Recommended Citation Nelson, Hayley, "Disease and insect pest management in organic cucurbit production" (2019). Graduate Theses and Dissertations. 17066. https://lib.dr.iastate.edu/etd/17066 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Disease and insect pest management in organic cucurbit production by Hayley Marie Nelson A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Major: Plant Pathology Program of Study Committee: Mark L. Gleason, Major Professor Gwyn A. Beattie Erin W. Hodgson Ajay Nair Alison E. Robertson The student author, whose presentation of the scholarship herein was approved by the program of study committee, is solely responsible for the content of this thesis. The Graduate College will ensure this thesis is globally accessible and will not permit alterations after a degree is conferred. Iowa State University
    [Show full text]
  • Diversity and Abundance of Pest Insects Associated with Solanum Tuberosum L
    American Journal of Entomology 2021; 5(3): 51-69 http://www.sciencepublishinggroup.com/j/aje doi: 10.11648/j.aje.20210503.13 ISSN: 2640-0529 (Print); ISSN: 2640-0537 (Online) Diversity and Abundance of Pest Insects Associated with Solanum tuberosum L. 1753 (Solanaceae) in Balessing (West-Cameroon) Babell Ngamaleu-Siewe, Boris Fouelifack-Nintidem, Jeanne Agrippine Yetchom-Fondjo, Basile Moumite Mohamed, Junior Tsekane Sedick, Edith Laure Kenne, Biawa-Miric Kagmegni, * Patrick Steve Tuekam Kowa, Romaine Magloire Fantio, Abdel Kayoum Yomon, Martin Kenne Department of the Biology and Physiology of Animal Organisms, University of Douala, Douala, Cameroon Email address: *Corresponding author To cite this article: Babell Ngamaleu-Siewe, Boris Fouelifack-Nintidem, Jeanne Agrippine Yetchom-Fondjo, Basile Moumite Mohamed, Junior Tsekane Sedick, Edith Laure Kenne, Biawa-Miric Kagmegni, Patrick Steve Tuekam Kowa, Romaine Magloire Fantio, Abdel Kayoum Yomon, Martin Kenne. Diversity and Abundance of Pest Insects Associated with Solanum tuberosum L. 1753 (Solanaceae) in Balessing (West-Cameroon). American Journal of Entomology . Vol. 5, No. 3, 2021, pp. 51-69. doi: 10.11648/j.aje.20210503.13 Received : July 14, 2021; Accepted : August 3, 2021; Published : August 11, 2021 Abstract: Solanum tuberosum L. 1753 (Solanaceae) is widely cultivated for its therapeutic and nutritional qualities. In Cameroon, the production is insufficient to meet the demand in the cities and there is no published data on the diversity of associated pest insects. Ecological surveys were conducted from July to September 2020 in 16 plots of five development stages in Balessing (West- Cameroon). Insects active on the plants were captured and identified and the community structure was characterized.
    [Show full text]
  • Flea Beetles
    E-74-W Vegetable Insects Department of Entomology FLEA BEETLES Rick E. Foster and John L. Obermeyer, Extension Entomologists Several species of fl ea beetles are common in Indiana, sometimes causing damage so severe that plants die. Flea beetles are small, hard-shelled insects, so named because their enlarged hind legs allow them to jump like fl eas from plants when disturbed. They usually move by walking or fl ying, but when alarmed they can jump a considerable distance. Most adult fl ea beetle damage is unique in appearance. They feed by chewing a small hole (often smaller than 1/8 inch) in a leaf, moving a short distance, then chewing another hole and so on. The result looks like a number of “shot holes” in the leaf. While some of the holes may meet, very often they do not. A major exception to this characteristic type of damage is that caused by the corn fl ea beetle, which eats the plant tissue forming narrow lines in the corn leaf surface. This damage gives plants a greyish appearance. Corn fl ea beetle damage on corn leaf (Photo Credit: John Obermeyer) extent of damage is realized. Therefore, it is very important to regularly check susceptible plants, especially when they are in the seedling stage. Most species of fl ea beetles emerge from hibernation in late May and feed on weeds and other plants, if hosts are not available. In Indiana, some species have multiple generations per year, and some have only one. Keeping fi elds free of weed hosts will help reduce fl ea beetle populations.
    [Show full text]
  • University of W Isconsin G Arden Facts
    XHT1092 Provided to you by: Cucumber Beetles David M. Lowenstein and Russell L. Groves, UW-Madison, Department of Entomology Striped and spotted cucumber beetles are common pests of vine crops (e.g., cucumber, squash, pumpkin, watermelon) that can cause severe damage to roots, leaves, flowers and fruits, as well as interfere with pollination, leading to reduced fruit set. In Wisconsin, the striped cucumber beetle is the more common of the two insects. In addition to direct damage from their feeding, cucumber beetles can contribute to indirect vine crop damage because they can carry and transmit disease- causing bacteria and viruses. Appearance: Striped cucumber beetle 3 (Acalymma vittatum) adults are between /16 and 1 /4 inches long and yellow-green in color with three black stripes running the length of their bodies. They are often confused with western corn rootworm beetles, which are not vine crop pests, but which are often found feeding on vine crop pollen. You can distinguish between these two insects by examining their undersides. Striped cucumber beetles have black abdomens; western corn rootworms have yellow-green abdomens. Spotted cucumber beetle (Diabrotica undecimpunctata) adults are similar in size to striped cucumber beetle adults and are yellow- green except for their black heads and 12 black spots on their backs. Larvae of both types of cucumber beetle live in the soil and are worm-like, Striped cucumber beetle (top) and spotted are white with a dark head, and have three pairs cucumber beetle (bottom). of legs. Symptoms and Effects: Cucumber beetle larvae feed on roots and stems, and they can stunt or kill seedlings and transplants when present in large numbers.
    [Show full text]
  • Key Plant, Key Pests: Baldcypress (Taxodium Distichum)1 Juanita Popenoe, Caroline R
    ENH1293 Key Plant, Key Pests: Baldcypress (Taxodium distichum)1 Juanita Popenoe, Caroline R. Warwick, and Roger Kjelgren2 “knees,” a distinct structure that forms above the roots. They will also grow well in upland sites with few to no “knees” (Gilman and Watson 2014). Key Pests: Baldcypress This series of Key Plant, Key Pests publications is designed for Florida gardeners, horticulturalists, and landscape professionals to help identify common pests associated with common Florida flora. This publication, the first in the Key Plant, Key Pests series, helps identify the most common pests found on the Baldcypress (Taxodium distichum). This publication provides information and general Figure 1. Baldcypress trees can often be seen on lake and river shores management recommendations for the cypress leaf beetle, throughout Florida. Credits: Tyler Jones, UF/IFAS fall webworm, cypress twig gall midge, mealybugs, rust mites, and needle blights. For a more comprehensive guide Key Plant: Baldcypress (Taxodium of woody ornamental insect management, download the current Professional Disease Management Guide for Orna- distichum) mental Plants here or the Integrated Pest Management in the Baldcypress (Taxodium distichum (L.) Rich.) are deciduous- Commercial Ornamental Nursery Guide here. needled pyramidal trees that can reach 100 to 150 feet in height. They grow at a moderately fast rate, reaching 40 to Cypress Leaf Beetle: Systena marginalis 50 feet in the first 15 to 25 years. They are commonly found Recognition: Foliage will appear discolored, turning into throughout the state of Florida, particularly near lakes a bright to dark red with small, linear gouges (approx. and rivers (as they are native to wetlands along running 1/10-inch long) in the needles.
    [Show full text]