Insect Vectors of Phytoplasmas - R
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Morphology and Adaptation of Immature Stages of Hemipteran Insects
© 2019 JETIR January 2019, Volume 6, Issue 1 www.jetir.org (ISSN-2349-5162) Morphology and Adaptation of Immature Stages of Hemipteran Insects Devina Seram and Yendrembam K Devi Assistant Professor, School of Agriculture, Lovely Professional University, Phagwara, Punjab Introduction Insect Adaptations An adaptation is an environmental change so an insect can better fit in and have a better chance of living. Insects are modified in many ways according to their environment. Insects can have adapted legs, mouthparts, body shapes, etc. which makes them easier to survive in the environment that they live in and these adaptations also help them get away from predators and other natural enemies. Here are some adaptations in the immature stages of important families of Hemiptera. Hemiptera are hemimetabolous exopterygotes with only egg and nymphal immature stages and are divided into two sub-orders, homoptera and heteroptera. The immature stages of homopteran families include Delphacidae, Fulgoridae, Cercopidae, Cicadidae, Membracidae, Cicadellidae, Psyllidae, Aleyrodidae, Aphididae, Phylloxeridae, Coccidae, Pseudococcidae, Diaspididae and heteropteran families Notonectidae, Corixidae, Belastomatidae, Nepidae, Hydrometridae, Gerridae, Veliidae, Cimicidae, Reduviidae, Pentatomidae, Lygaeidae, Coreidae, Tingitidae, Miridae will be discussed. Homopteran families 1. Delphacidae – Eg. plant hoppers They comprise the largest family of plant hoppers and are characterized by the presence of large, flattened spurs at the apex of their hind tibiae. Eggs are deposited inside plant tissues, elliptical in shape, colourless to whitish. Nymphs are similar in appearance to adults except for size, colour, under- developed wing pads and genitalia. 2. Fulgoridae – Eg. lantern bugs They can be recognized with their antennae inserted on the sides & beneath the eyes. -
Asian Citrus Psyllid, Diaphorina Citri Kuwayama (Insecta: Hemiptera: Psyllidae)1 F
EENY-033 Asian Citrus Psyllid, Diaphorina citri Kuwayama (Insecta: Hemiptera: Psyllidae)1 F. W. Mead and T. R. Fasulo2 Introduction In June 1998, the insect was detected on the east coast of Florida, from Broward to St. Lucie counties, and was The Asian citrus psyllid, Diaphorina citri Kuwayama, is apparently limited to dooryard host plantings at the time of widely distributed in southern Asia. It is an important pest its discovery. By September 2000, this pest had spread to 31 of citrus in several countries as it is a vector of a serious Florida counties (Halbert 2001). citrus disease called greening disease or Huanglongbing. This disease is responsible for the destruction of several Diaphorina citri is often referred to as citrus psylla, but this citrus industries in Asia and Africa (Manjunath 2008). is the same common name sometimes applied to Trioza Until recently, the Asian citrus psyllid did not occur in erytreae (Del Guercio), the psyllid pest of citrus in Africa. North America or Hawaii, but was reported in Brazil, by To avoid confusion, T. erytreae should be referred to as the Costa Lima (1942) and Catling (1970). African citrus psyllid or the two-spotted citrus psyllid (the latter name is in reference to a pair of spots on the base of the abdomen in late stage nymphs). These two psyllids are the only known vectors of the etiologic agent of citrus greening disease (Huanglongbing), and are the only eco- nomically important psyllid species on citrus in the world. Six other species of Diaphorina are reported on citrus, but these are non-vector species of relatively little importance (Halbert and Manjunath 2004). -
UNIVERSITÀ DEGLI STUDI DEL MOLISE Department
UNIVERSITÀ DEGLI STUDI DEL MOLISE Department of Agricultural, Environmental and Food Sciences Ph.D. course in: AGRICULTURE TECHNOLOGY AND BIOTECHNOLOGY (CURRICULUM: Sustainable plant production and protection) (CYCLE XXIX) Ph.D. thesis NEW INSIGHTS INTO THE BIOLOGY AND ECOLOGY OF THE INSECT VECTORS OF APPLE PROLIFERATION FOR THE DEVELOPMENT OF SUSTAINABLE CONTROL STRATEGIES Coordinator of the Ph.D. course: Prof. Giuseppe Maiorano Supervisor: Prof. Antonio De Cristofaro Co-Supervisor: Dr. Claudio Ioriatti Ph.D. student: Tiziana Oppedisano Matr: 151603 2015/2016 “Nella vita non c’è nulla da temere, c’è solo da capire.” (M. Curie) Index SUMMARY 5 RIASSUNTO 9 INTRODUCTION 13 Phytoplasmas 13 Taxonomy 13 Morphology 14 Symptomps 15 Transmission and spread 15 Detection 17 Phytoplasma transmission by insect vectors 17 Phytoplasma-vector relationship 18 Homoptera as vectors of phytoplasma 19 ‘Candidatus Phytoplasma mali’ 21 Symptomps 21 Distribution in the tree 22 Host plant 24 Molecular characterization and diagnosis 24 Geographical distribution 25 AP in Italy 25 Transmission of AP 27 Psyllid vectors of ‘Ca. P. mali’ 28 Cacopsylla picta Förster (1848) 29 Cacopsylla melanoneura Förster (1848) 32 Other known vectors 36 Disease control 36 Aims of the research 36 References 37 CHAPTER 1: Apple proliferation in Valsugana: three years of disease and psyllid vectors’ monitoring 49 CHAPTER 2: Evaluation of the current vectoring efficiency of Cacopsylla melanoneura and Cacopsylla picta in Trentino 73 CHAPTER 3: The insect vector Cacopsylla picta vertically -
Biodiversa-Project Description-Final Version-110213
1.A. Detailed description of the research area and research plan Context of the proposal Biological invasions (bioinvasions) are defined as the successful establishment and spread of species outside their native range. They act as a major driver of global changes in species distribution. Diverse organisms and ecosystems may be involved, and although not all invasions have a negative impact, the ecological consequences often include the loss of native biological diversity and changes in community structure and ecosystem activity. There may also be additional negative effects on agriculture, forests, fisheries, and human health. National governments, intergovernmental structures like the European Commission and international organizations such as EPPO, CABI and IUCN have therefore mobilized to (i) introduce international laws on invasive species, (ii) organize international networks of scientists and stakeholders to study bioinvasions, and (iii) formalize the cooperation between national environmental or agricultural protection agencies (e.g. the French Agence Nationale de Sécurité Sanitaire, ANSES). Several billion euros are spent annually to address the problems caused by bioinvasions and the scientific community has focused on predicting and controlling future invasions by understanding how they occur. A peer-reviewed journal entitled "Biological Invasions” has been published since 1999. Ecologists have long drawn attention to the negative ecological effects of invasive species, whereas the evolutionary aspects of bioinvasions have received comparatively little attention. This reflects the fact that: i) invasive populations were thought to experience significant bottlenecks during their introduction to new environments and thus possess a limited potential to evolve; and ii) evolution was considered too slow to play a significant role given the relatively short timescale of the invasion process. -
Studies on the Biology of the Sugar-Cane Pest Saccharosydne Saccharivora (Westw.) (Horn., Delphacidae)
Bull. ent. Res. (1968) 59, 393^08 393 With Plates XVII-XVIII Published 1969 Studies on the biology of the sugar-cane pest Saccharosydne saccharivora (Westw.) (Horn., Delphacidae) J. R. METCALFE * Sugar Manufacturer? Association Ltd, Mandeville, Jamaica Introduction Saccharosydne saccharivora (Westw.), commonly known as the West Indian cane fly, is found on sugar-cane throughout the West Indies and neighbouring parts of North, South and Central America, and in Jamaica has been a major pest of sugar-cane for more than two centuries. It may pass almost unnoticed for years, but at irregular inter- vals, shorter in Jamaica than elsewhere, epidemic populations develop and may retard the growth of the crop, on occasion posing a serious threat to the sugar industry. There are many references to its outbreaks and natural enemies, yet its original host-plants are almost unknown and surprisingly little has been written of its life-history and habits. The accounts by Ballou (1905) and Wolcott (1921, 1933) lack developmental details, while that of Guagliumi (1953) contains, as will be shown, serious inaccuracies. Ashby's (1954) unpublished report is the most useful account to date but, being based on investigations lasting less than two months, is necessarily limited in scope. This paper presents an account of laboratory studies and field observations in Jamaica and British Honduras between 1961 and 1967 on the host-plants, life-history and habits of S. saccharivora. Host-plants Sugar-cane, introduced to the West Indies in the late 15th century, has been available to S. saccharivora as a possible host-plant for little more than 450 years. -
Effects of Lethal Bronzing Disease, Palm Height, and Temperature On
insects Article Effects of Lethal Bronzing Disease, Palm Height, and Temperature on Abundance and Monitoring of Haplaxius crudus De-Fen Mou 1,* , Chih-Chung Lee 2, Philip G. Hahn 3, Noemi Soto 1, Alessandra R. Humphries 1, Ericka E. Helmick 1 and Brian W. Bahder 1 1 Fort Lauderdale Research and Education Center, Department of Entomology and Nematology, University of Florida, 3205 College Ave., Ft. Lauderdale, FL 33314, USA; sn21377@ufl.edu (N.S.); ahumphries@ufl.edu (A.R.H.); ehelmick@ufl.edu (E.E.H.); bbahder@ufl.edu (B.W.B.) 2 School of Biological Sciences, University of Nebraska-Lincoln, 412 Manter Hall, Lincoln, NE 68588, USA; [email protected] 3 Department of Entomology and Nematology, University of Florida, 1881 Natural Area Dr., Gainesville, FL 32608, USA; hahnp@ufl.edu * Correspondence: defenmou@ufl.edu; Tel.: +1-954-577-6352 Received: 5 October 2020; Accepted: 28 October 2020; Published: 30 October 2020 Simple Summary: Phytopathogen-induced changes often affect insect vector feeding behavior and potentially pathogen transmission. The impacts of pathogen-induced plant traits on vector preference are well studied in pathosystems but not in phytoplasma pathosystems. Therefore, the study of phytoplasma pathosystems may provide important insight into controlling economically important phytoplasma related diseases. In this study, we aimed to understand the impacts of a phytoplasma disease in palms on the feeding preference of its potential vector. We investigated the effects of a palm-infecting phytoplasma, lethal bronzing (LB), on the abundance of herbivorous insects. These results showed that the potential vector, Haplaxius crudus, is more abundant on LB-infected than on healthy palms. -
'Candidatus Phytoplasma Solani' (Quaglino Et Al., 2013)
‘Candidatus Phytoplasma solani’ (Quaglino et al., 2013) Synonyms Phytoplasma solani Common Name(s) Disease: Bois noir, blackwood disease of grapevine, maize redness, stolbur Phytoplasma: CaPsol, maize redness phytoplasma, potato stolbur phytoplasma, stolbur phytoplasma, tomato stolbur phytoplasma Figure 1: A ‘dornfelder’ grape cultivar Type of Pest infected with ‘Candidatus Phytoplasma Phytoplasma solani’. Courtesy of Dr. Michael Maixner, Julius Kühn-Institut (JKI). Taxonomic Position Class: Mollicutes, Order: Acholeplasmatales, Family: Acholeplasmataceae Genus: ‘Candidatus Phytoplasma’ Reason for Inclusion in Manual OPIS A pest list, CAPS community suggestion, known host range and distribution have both expanded; 2016 AHP listing. Background Information Phytoplasmas, formerly known as mycoplasma-like organisms (MLOs), are pleomorphic, cell wall-less bacteria with small genomes (530 to 1350 kbp) of low G + C content (23-29%). They belong to the class Mollicutes and are the putative causal agents of yellows diseases that affect at least 1,000 plant species worldwide (McCoy et al., 1989; Seemüller et al., 2002). These minute, endocellular prokaryotes colonize the phloem of their infected plant hosts as well as various tissues and organs of their respective insect vectors. Phytoplasmas are transmitted to plants during feeding activity by their vectors, primarily leafhoppers, planthoppers, and psyllids (IRPCM, 2004; Weintraub and Beanland, 2006). Although phytoplasmas cannot be routinely grown by laboratory culture in cell free media, they may be observed in infected plant or insect tissues by use of electron microscopy or detected by molecular assays incorporating antibodies or nucleic acids. Since biological and phenotypic properties in pure culture are unavailable as aids in their identification, analysis of 16S rRNA genes has been adopted instead as the major basis for phytoplasma taxonomy. -
Diversity and Abundance of Insect Herbivores Foraging on Seedlings in a Rainforest in Guyana
R Ecological Entomology (1999) 24, 245±259 Diversity and abundance of insect herbivores foraging on seedlings in a rainforest in Guyana YVES BASSET CABI Bioscience: Environment, Ascot, U.K. Abstract. 1. Free-living insect herbivores foraging on 10 000 tagged seedlings representing ®ve species of common rainforest trees were surveyed monthly for more than 1 year in an unlogged forest plot of 1 km2 in Guyana. 2. Overall, 9056 insect specimens were collected. Most were sap-sucking insects, which represented at least 244 species belonging to 25 families. Leaf-chewing insects included at least 101 species belonging to 16 families. Herbivore densities were among the lowest densities reported in tropical rainforests to date: 2.4 individuals per square metre of foliage. 3. Insect host speci®city was assessed by calculating Lloyd's index of patchiness from distributional records and considering feeding records in captivity and in situ. Generalists represented 84 and 78% of sap-sucking species and individuals, and 75 and 42% of leaf-chewing species and individuals. In particular, several species of polyphagous xylem-feeding Cicadellinae were strikingly abundant on all hosts. 4. The high incidence of generalist insects suggests that the Janzen±Connell model, explaining rates of attack on seedlings as a density-dependent process resulting from contagion of specialist insects from parent trees, is unlikely to be valid in this study system. 5. Given the rarity of ¯ushing events for the seedlings during the study period, the low insect densities, and the high proportion of generalists, the data also suggest that seedlings may represent a poor resource for free-living insect herbivores in rainforests. -
VINEYARD BIODIVERSITY and INSECT INTERACTIONS! ! - Establishing and Monitoring Insectariums! !
! VINEYARD BIODIVERSITY AND INSECT INTERACTIONS! ! - Establishing and monitoring insectariums! ! Prepared for : GWRDC Regional - SA Central (Adelaide Hills, Currency Creek, Kangaroo Island, Langhorne Creek, McLaren Vale and Southern Fleurieu Wine Regions) By : Mary Retallack Date : August 2011 ! ! ! !"#$%&'(&)'*!%*!+& ,- .*!/'01)!.'*&----------------------------------------------------------------------------------------------------------------&2 3-! "&(')1+&'*&4.*%5"/0&#.'0.4%/+.!5&-----------------------------------------------------------------------------&6! ! &ABA <%5%+3!C0-72D0E2!AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!F! &A&A! ;D,!*2!G*0.*1%-2*3,!*HE0-3#+3I!AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!J! &AKA! ;#,2!0L!%+D#+5*+$!G*0.*1%-2*3,!*+!3D%!1*+%,#-.!AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!B&! 7- .*+%)!"/.18+&--------------------------------------------------------------------------------------------------------------&,2! ! ! KABA ;D#3!#-%!*+2%53#-*MH2I!AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!BN! KA&A! O3D%-!C#,2!0L!L0-H*+$!#!2M*3#G8%!D#G*3#3!L0-!G%+%L*5*#82!AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!&P! KAKA! ?%8%53*+$!3D%!-*$D3!2E%5*%2!30!E8#+3!AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA!&B! 9- :$"*!.*;&5'1/&.*+%)!"/.18&-------------------------------------------------------------------------------------&3<! -
Pl Path 502 Phytoplasma
Phytoplasmas Pl. Path. 502 Dr. PN SHARMA Department of Plant Pathology CSK HP Agricultural University Palampur-176 062 (HP State) INDIA What are Phytoplasmas ? Phytoplasmas have diverged from gram-positive eubacteria, and belong to the Genus Phytoplasma within the Class Mollicutes. Mycoplasmas dramatically differ phenotypically from other bacteria by their minute size (0.3 - 0.5 and lack of cell wall. The lack of cell wall was used to separate mycoplasmas from other bacteria in a class named Mollicutes. Due to degenerative or reductive evolution, accompanied by significant losses of genomic sequences, the genomes of mollicutes have shrunk and are relatively small compared to other bacteria, ranging from 580 kb. to 2,200 kb. Phytoplasma •Phytoplasma are wall-less prokaryotic organisms •Seen with electron microscope in the phloem of infected plant •Unable to grow on culture media •Pleomorphic shaped and spiral Phytoplasma •Most phytoplasma transmitted from plant to plant by • leafhoppers, • but some are transmitted by Psyllids and planthoppers •Caused Yellowing, Big bud, Stuntting, Witchbroom •Sensitive to antibiotics, especially Tetracycline group Mycoplasma (Phytoplsma): Doi et al. (1970) are submicroscopic, measuring 150- 300 nm in diameter having ribosomes and DNA strands enclosed by a bilayer membrane but not the cell wall, replicate by binary fission, can be cultured artificially in vitro on specific medium and are sensitive to certain antibiotics (tetracycline not to penicillin). E.g. Little leaf of brinjal, Peach yellow Spiroplasm citri (Fudt Allh et al. 1571) Citrus stubbesh. Classification Class : Mollicutes Order: Mycoplasmatales. Three families, each with one genus: Mycoplasmataceae, genus Mycoplasma, Acholeplasmataceae, . genus Acholeplasma, Spiroplasmataceae . genus Spiroplasma. -
Saccharosydne Saccharivora, the West Indian Canefly (Hemiptera: Delphacidae) Blake Wilson, Megan Mulcahy, Forest Huval and Gene Reagan
Saccharosydne saccharivora, The West Indian Canefly (Hemiptera: Delphacidae) Blake Wilson, Megan Mulcahy, Forest Huval and Gene Reagan Description Damage to Sugarcane Saccharosydne saccharivora, known as the West The West Indian canefly is originally from Jamaica Indian canefly, is a true bug belonging to the insect family and other parts of the Caribbean. The species was first Delphacidae. The family belongs to a group referred discovered in Louisiana in 1944. All life stages of the to as plant hoppers. The adult West Indian canefly is a West Indian canefly feed on grasses, such as sugarcane, distinctive bright green insect with red eyes and clear johnsongrass, sudangrass, switchgrass and bushy bluestem. wings. They possess black lines on their yellowish The species has also been introduced to other areas of antennae and a narrow head that protrudes beyond the the southern U.S. from Florida to Texas. eyes, almost like a nose. Adults are usually 3 to 5 mm (one-eighth to one-fifth of an inch) in length. Females are slightly larger than males. Female West Indian caneflies can also be identified by a cottony substance secreted from the end of the abdomen. The immature stage nymphs are smaller than the adults, greenish-yellow, wingless and possess a distinctive tail of waxy secretions. They resemble the adults more with each growth stage. Life History Eggs of the West Indian canefly are laid in ridges on the undersides of host plant leaves. The eggs are then covered in protective webbing, giving them a cottony appearance. The egg stage lasts about 13 to 23 days, depending on temperature, with peak hatching occurring at 15 to 16 days. -
2003Session3.Pdf
THE SITUATION OF GRAPEVINE YELLOWS AND CURRENT RESEARCH DIRECTIONS: DISTRIBUTION, DIVERSITY, VECTORS, DIFFUSION AND CONTROL E. Boudon-Padieu Biologie et écologie des phytoplasmes, UMR 1088 Plante Microbe Environnement, INRA – Université de Bourgogne, Domaine d’Epoisses, BP 86510 – 21065 Dijon Cedex France Grapevine yellows (GY) are known now for 50 years. After the first appearance of Flavescence dorée (FD) in West-South France in the 1950’s, similar diseases have been observed in vineyards of other regions or countries (22) in Europe, North-America, Asia Minor and Australia. Typical symptoms are leaf rolling and discoloration of veins and laminae, uneven or total lack of lignification of canes, flower abortion or berry withering. Eventually, severe decline and death occur with sensitive varieties or with particular GY diseases. All these diseases have been associated with phytoplasmas. Phytoplasmas, discovered in 1967, are wall-less intracellular bacterias restricted to phloem sieve tubes and transmitted only by vector insects in which they multiply and circulate. Recently, comparisons of conserved regions in their genomic DNA, have permitted to classify all known phytoplasmas into about 20 groups and subgroups within a monophyletic clade in the Class Mollicutes, closest to the Acholeplasma clade (57, 78). Numerous DNA probes have been designed that permit diagnosis and identification of phytoplasmas in plant tissues and in insects. This, together with transmission assays, has also permitted the recent identification of new phytoplasma vectors. Though Koch’s postulate cannot be fully satisfied with non-culturable pathogen agents, it is now considered that phytoplasmas are responsible for typical GY symptoms. These conclusions have been reached because of transmission experiments with natural vectors in the case of Flavescence dorée (FD) and Bois noir (BN), of the similarity of symptoms caused world wide by GY diseases on numerous grapevine cultivars and of consistent detection of phytoplasmas in affected grapevines and in infective insect vectors.