DOCSLIB.ORG

Evolutionary Ecology of Diamondback Moth, Plutella Xylostella (L.) and Diadegma Insulare (Cresson) in North America: a Review

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Evolutionary Ecology of Diamondback Moth, Plutella Xylostella (L.) and Diadegma Insulare (Cresson) in North America: a Review Annual Research & Review in Biology 5(3): 189-206, 2015, Article no.ARRB.2015.021 ISSN: 2347-565X SCIENCEDOMAIN international www.sciencedomain.org Evolutionary Ecology of Diamondback Moth, Plutella xylostella (L .) and Diadegma insulare (Cresson) in North America: A Review Sadia Munir 1* , Lloyd M. Dosdall 1 and John T. O’Donovan 2 1Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada. 2Lacombe Research Centre, Agriculture and Agri-Food Canada, 6000 C and E Trail, Lacombe, AB, T4L 1W1, Canada. Authors’ contributions This work was carried out in collaboration between all authors. Author SM managed the literature searches and wrote the first draft of the manuscript. Author LMD supervised and critically reviewed the manuscript and author JTO helped in editing and final revision of manuscript. All authors read and approved the final manuscript. Article Information DOI: 10.9734/ARRB/2015/11834 Editor(s): (1) George Perry, Dean and Professor of Biology, University of Texas at San Antonio, USA. Reviewers: (1) Anonymous, Osmania University, India. (2) Anonymous, Southwest University, China. (3) Isabel Bertolaccini, Department of Plant Production, Facultad de Ciencias Agrarias (U.N.L.), Kreder 2805, (3080) Esperanza (Santa Fe), Argentina. Complete Peer review History: http://www.sciencedomain.org/review-history.php?iid=668&id=32&aid=6211 Received 5th June 2014 th Review Article Accepted 7 July 2014 Published 24 th September 2014 ABSTRACT The diamondback moth (DBM), Plutella xylostella (L.), is recognized as a widely distributed destructive insect pest of Brassicaceae. The frequency and severity of P. xylostella outbreaks has increased in recent years, due to climate changes, high production of host plants (vegetable and oilseed Brassica crops), genetic flexibility of the pest that enables it to develop resistance to almost all known insecticides and establish quickly and easily in new environment. All life stages of P. xylostella are attacked by natural enemies but Diadegma insulare (Cresson) is one of the principal, effective and efficient larval parasitoids in North America. In this review, we synthesize published information on the primary aspects of P. xylostella origin, dispersal, migration, biology, and host plants and mainly focus on evolutionary ecology of bitrophic and tritrophic interactions among P. xylostella , its host plants and natural enemies. _____________________________________________________________________________________________________ *Corresponding author: Email: [email protected]; Munir et al.; ARRB, 5(3): 189-206, 2015; Article no.ARRB.2015.021 Keywords: Evolution; ecology; Diamondback moth; host plant; Diadegma insulare. 1. INTRODUCTION population in an area is regulated by climate, availability and quality of host plants and the Plutella xylostella is not only the most destructive presence of its natural enemies [10]. pest of brassicaceous crops throughout the world but is also among the most difficult to manage 3. BIOLOGY [1,2]. It was first introduced from Europe to North America (Illinois), in 1854. Plutella xylostella now The biology of P. xylostella has been studied occurs throughout North America, wherever its extensively in both laboratory and natural host plants are cultivated [3]. Its management conditions in relation to ecological factors. result in a US$4-5 billion annual cost to the However, its biological and developmental world economy [4]. A few review articles on P. parameters vary due to differences in host plant xylostella host-plant interactions, management species, temperature, and geographical and ecology have been published but a focus on population distribution [11]. The moth is detailed evolutionary ecology of tritrophic multivoltine and can produce four to 20 interactions among P. xylostella , its host plants generations per year in temperate and tropical and its principle parasitoid are lacking. The main regions, respectively [12,13]. In North America, it objective of this review paper is to address the can produce three to five generations per year gaps in the knowledge and understanding of P. [14]. At constant temperature, development can xylostella and D. insulare evolutionary ecology occur from 8-32ºC and under fluctuating and tritrophic interactions. It is believed that the temperature from 4 to 38ºC [15]. Plutella information presented here will encourage xylostella development has been studied by researchers to work on important aspects of P. Bahar et al. [16] at different constant (7,22,30ºC) xylostella and its natural enemies and help and fluctuating temperatures (0-14,15-29ºC, and designing appropriate management strategies 23-37ºC). The development was very slow at involving complete and in depth awareness of lowest constant (7ºC) and fluctuating tritrophic interactions in a particular agro- temperatures (0-14ºC) while fast development of ecosystem. P. xylostella was recorded at highest constant (30ºC) and fluctuating temperatures (23-30ºC). 2. DISTRIBUTION AND ORIGIN OF P. xylostella Plutella xylostella has four life stages: egg, larva, pupa and adult. Oviposition mainly occurs at Plutella xylostella is believed to be the most night in the first 24 to 48 hours of mating and widely distributed species of Lepidoptera, then declines gradually. Egg laying reaches zero occurring universally wherever Brassicaceae are in 10 days after adult emergence [11]. Each grown [1]. Six economically important species of female can lay more than 200 eggs either singly the Genus Plutella (Schrank) have been or in small clusters [17,18]. Oviposition is greatly recorded worldwide but only P. xylostella is influenced by host plant species. For instance, cosmopolitan in distribution [5]. It has been oviposition on brassicaceous host plant (Brassica recorded throughout tropical and temperate napus L.) is reported to be higher than non- zones, as far north as Iceland (60°N) and as far brassicaceous hosts (Cleome hassleriana Chod. south as New Zealand (45ºS) [6]. The and Tropaeolum majus L.) [19]. geographical origin of P. xylostella is uncertain. Some have speculated its origin in Europe [7], Eggs are oval and pale to strong yellow in color the Mediterranean area [8] or China [9]. It is also [11]. Egg hatching occurs in 4-8 days [14]. assumed to have evolved in South Africa, based Larvae are pale yellow in color having a dark on the diversity of endemic Brassica plants and head in early instars, and are light to dark green its indigenous diverse parasitoid fauna [5]. North colored in later instars. The larva has V-shaped American populations are most probably of anal legs. First-instar larvae are leaf miners, European origin and were introduced about 150 feeding in the spongy mesophyll tissue of leaves. years ago [7]. Recently, some climatic models Other larval instars feed on all tissues of leaves, have been developed to predict P. xylostella buds, flowers, stems, and siliques [11,20]. The distribution and seasonal phenology in areas of average development time from first to fourth its occasional occurrence. However, the instar is reported as 4.0, 3.6, 3.4, and 4.2 days abundance and distribution of the P. xylostella respectively, under Canadian field conditions; pupation takes place over 7.8 to 9.8 days [14]. 190 Munir et al.; ARRB, 5(3): 189-206, 2015; Article no.ARRB.2015.021 The adult moth is slender and greyish [21]. The 5. EVOLUTIONARY ECOLOGY OF mean longevity of females is significantly INTERACTIONS AMONG P. xylostella reduced relative to males [11]. Development and AND ITS HOST PLANTS survival vary greatly depending on quality of food, quantity of adult feeding, difference in host Plutella xylostella has a wide ecological host plant cultivar and sources of carbohydrate range. The genetic and phenotypic flexibility of P. [22,11]. xylostella , and its ability to modify traits of its life history according to environmental conditions 4. DISPERSAL AND MIGRATION during development enables the pest to survive throughout the year in areas where Migration may evolve as a mechanism that environmental conditions are favorable and host permits individuals to avoid probable failures in plants are easily available, in the absence of survival [23]. Insects may develop migratory other ecological and evolutionary pressures characteristics when their habitat deteriorates [28,37]. The moth feeds almost exclusively on [24]. Plutella xylostella possesses a high plants of the family Brassicaceae , particularly the migratory ability to disperse over long distances genus Brassica , which are widely distributed in a very short time. This can explain why it gets geographically, and include 338 genera and easily established in novel environments and 3709 species [38] (Table 1). newly planted Brassica crops [7,25,26]. Plutella xylostella does not diapause; therefore long- Plutella xylostella is commonly considered a distance immigration through aerial currents is a specialist on Brassicaceae . However, evidence major process affecting population outbreaks of its occasional occurrence on sugar snap peas [27,28]. Plutella xylostella migration and (Pisum sativum L., Fabaceae) in Kenya [70], population seasonality is well documented [1]. Taiwan and the Philippines [55,64], the Similar seasonal migrations have been reported chenopodiaceous vegetable Salsola kali L. in Japan's south western islands [29], in the (prickly saltwort, Russian thistle) in Russia [71], United Kingdom [7,30], New Zealand, South and okra in Ghana [72] have been recorded.
Load more

Recommended publications
  • Analysis of the Evolutionary Relationship and Geographical Patterns of Genetically Varied Populations of Diamondback Moth, Plutella Xylostella (L.)
    Analysis of the evolutionary relationship and geographical patterns of genetically varied populations of diamondback moth, Plutella xylostella (L.) by Shijun You MSc., The University of British Columbia, 2010 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Botany) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) October 2017 © Shijun You, 2017 Abstract The diamondback moth (DBM), Plutella xylostella, is well known for its extensive adaptation and distribution, high level of genetic variation and polymorphism, and strong resistance to a broad range of synthetic insecticides. Although understanding of the P. xylostella biology and ecology has been considerably improved, knowledge on the genetic basis of these traits remains surprisingly limited. Based on data generated by different sets of molecular markers, we uncovered the history of evolutionary origin and regional dispersal, identified the patterns of genetic diversity and variation, characterized the demographic history, and revealed natural and human-aided factors that are potentially responsible for contemporary distribution of P. xylostella. These findings rewrite our understanding of this exceptional system, revealing that South America might be a potential origin of P. xylostella, and recently colonized across most parts of the world resulting possibly from intensified human activities. With the data from selected continents, we demonstrated signatures of localized selection associated with environmental adaptation and insecticide resistance of P. xylostella. This work brings us to a better understanding of the regional movement and genetic bases on rapid adaptation and development of agrochemical resistance, and provides a solid foundation for better monitoring and management of this worldwide herbivore and forecast of regional pest status of P.
    [Show full text]
  • Is Diadegma Insulare Or Microplitis Plutellae a More Effective Parasitoid of the Diamondback Moth, Plutella Xylostella ?
    War of the Wasps: Is Diadegma insulare or Microplitis plutellae a More Effective Parasitoid of the Diamondback Moth, Plutella xylostella ? ADAMO YOUNG 108 Homestead Street, Ottawa Ontario K2E 7N6 Canada; email: [email protected] Young, Adamo. 2013. War of the wasps: is Diadegma insulare or Microplitis plutellae a more effective parasitoid of the Dia - mondback Moth, Plutella xylostella ? Canadian Field-Naturalist 127(3): 211–215. Parasitism levels by Diadegma insulare (Muesebeck) (Hymenoptera: Ichneumonidae) and Microplitis plutellae (Haliday) (Hymenoptera: Braconidae) at various densities of their host, Plutella xylostella (L.) (Lepidoptera: Plutellidae), were assessed. Cages with densities of 10 hosts, 20 hosts, and 40 hosts were set up, with the cage volume (40 500 cm 3) and number of wasps (2 females) remaining constant. The host populations were also exposed to the wasps for two different exposure times: 1 day and 3 days. The study showed that D. insulare was a better parasitoid overall, achieving a level of parasitism equal to or higher than M. plutellae at all densities. Microplitis plutellae performed best at a lower host density (76% ± 9% of 10 hosts vs. 43% ± 3% of 40 hosts). Diadegma insulare performed similarly at all densities tested (75% ± 5% of 10 hosts, 83% ± 4% of 20 hosts, and 79% ± 6% of 40 hosts). This suggests that D. insulare may be the better parasitoid overall and should be applied in severe, large-scale infestations, while M. plutellae may be better for small-scale infestations. Key Words: Diamondback Moth; Plutella xylostella; Microplitis plutellae; Diadegma insulare; parasitoids; biological control Introduction ical control can provide better control than pesticides.
    [Show full text]
  • Improving Integrated Crop Management by Conserving Natural Enemies of Insect Pests
    Improving Integrated Crop Management by Conserving Natural Enemies of Insect Pests Dr. Lloyd Dosdall, Department of Agricultural, Food and Nutritional Science, University of Alberta and Doug Moisey, Canola Council of Canada Project Code: CARP 2004-01 Final Report: March 2007 Field studies were undertaken in southern Alberta and Saskatchewan during the 2006 field season to investigate different management strategies for enhancing the effectiveness of natural enemies of cabbage seedpod weevil and diamondback moth in canola. The study showed that the level of parasitism of the cabbage seedpod weevil has increased dramatically in recent years, and the hymenopteran wasp, Diadegma insulare, is capable of causing significant reductions in diamondback moth populations. Canola growers in regions infested with damaging infestations of cabbage seedpod weevil should maintain recommended seeding rates 2.5 to 4.5 lb/acre (3 to 5 kg/ha) for optimal yields and consistent times to crop maturity. However, early seeding (late April) predisposes the crop to greater attack by the cabbage seedpod weevil and should be avoided. Canola insect pests are subject to attack by a wide range of natural enemies, comprising parasitoids, predators, and pathogens, many of which help limit or reduce pest populations. However, in spite of their economic importance, comparatively little is known of their biology and the factors that can enhance their effectiveness. The cabbage seedpod weevil, Ceutorhynchus obstrictus and the diamondback moth, Plutella xylostella are two important insect pests of canola in western Canada that can be subject to considerable population mortality by natural enemies. In this project, field studies were conducted in southern Alberta and Saskatchewan during the 2006 field season to investigate aspects of improved integrated crop management by conserving natural enemies of the cabbage seedpod weevil and the diamondback moth.
    [Show full text]
  • Variation Among 532 Genomes Unveils the Origin and Evolutionary
    ARTICLE https://doi.org/10.1038/s41467-020-16178-9 OPEN Variation among 532 genomes unveils the origin and evolutionary history of a global insect herbivore ✉ Minsheng You 1,2,20 , Fushi Ke1,2,20, Shijun You 1,2,3,20, Zhangyan Wu4,20, Qingfeng Liu 4,20, ✉ ✉ Weiyi He 1,2,20, Simon W. Baxter1,2,5, Zhiguang Yuchi 1,6, Liette Vasseur 1,2,7 , Geoff M. Gurr 1,2,8 , Christopher M. Ward 9, Hugo Cerda1,2,10, Guang Yang1,2, Lu Peng1,2, Yuanchun Jin4, Miao Xie1,2, Lijun Cai1,2, Carl J. Douglas1,2,3,21, Murray B. Isman 11, Mark S. Goettel1,2,12, Qisheng Song 1,2,13, Qinghai Fan1,2,14, ✉ Gefu Wang-Pruski1,2,15, David C. Lees16, Zhen Yue 4 , Jianlin Bai1,2, Tiansheng Liu1,2, Lianyun Lin1,5, 1234567890():,; Yunkai Zheng1,2, Zhaohua Zeng1,17, Sheng Lin1,2, Yue Wang1,2, Qian Zhao1,2, Xiaofeng Xia1,2, Wenbin Chen1,2, Lilin Chen1,2, Mingmin Zou1,2, Jinying Liao1,2, Qiang Gao4, Xiaodong Fang4, Ye Yin4, Huanming Yang4,17,19, Jian Wang4,18,19, Liwei Han1,2, Yingjun Lin1,2, Yanping Lu1,2 & Mousheng Zhuang1,2 The diamondback moth, Plutella xylostella is a cosmopolitan pest that has evolved resistance to all classes of insecticide, and costs the world economy an estimated US $4-5 billion annually. We analyse patterns of variation among 532 P. xylostella genomes, representing a worldwide sample of 114 populations. We find evidence that suggests South America is the geographical area of origin of this species, challenging earlier hypotheses of an Old-World origin.
    [Show full text]
  • The Origins of Infestations of Diamondback Moth, Plutella Xylostella (L.), in Canola in Western Canada L.M. Dosdall1, P.G. Mason
    The management of diamondback moth and other crucifer pests The origins of infestations of diamondback moth, Plutella xylostella (L.), in canola in western Canada L.M. Dosdall1, P.G. Mason2, O. Olfert3, L. Kaminski3, and B.A. Keddie4 1Dept. of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada T6G 2P5 2Agriculture and Agri-Food Canada, 960 Carling Ave., Ottawa, ON, Canada K1A 0C6 3Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK, Canada S7N 0X2 4Dept. of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E9 Corresponding author: [email protected] Abstract Recent evidence that a population of Plutella xylostella (L.) overwintered successfully in western Canada prompted studies to evaluate overwintering survival of diamondback moth under field conditions in Alberta and Saskatchewan. Successful overwintering was not demonstrated at either site for any life stage under a variety of tillage and organic matter treatments, using either laboratory-reared or field-acclimated specimens of diamondback moth. Diamondback moth infestations in western Canada evidently originate primarily from southern U.S.A. or Mexico when strong winds carry adults northward in spring. To provide early warning predictions of infestations, air parcel trajectories into western Canada were investigated for monitoring long-range movement of P. xylostella early in the season. Using wind fields generated by the Canadian Meteorological Centre’s Global Environmental Multiscale model, three-dimensional air parcel trajectories were calculated using time-forward (prognostic) and time-backward (diagnostic) modes for several sites in North America. The model predicted strong northerly airflow in May 2001 which coincided with the occurrence of massive infestations of diamondback moth in canola in western Canada.
    [Show full text]
  • The Taxonomy of the Side Species Group of Spilochalcis (Hymenoptera: Chalcididae) in America North of Mexico with Biological Notes on a Representative Species
    University of Massachusetts Amherst ScholarWorks@UMass Amherst Masters Theses 1911 - February 2014 1984 The taxonomy of the side species group of Spilochalcis (Hymenoptera: Chalcididae) in America north of Mexico with biological notes on a representative species. Gary James Couch University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/theses Couch, Gary James, "The taxonomy of the side species group of Spilochalcis (Hymenoptera: Chalcididae) in America north of Mexico with biological notes on a representative species." (1984). Masters Theses 1911 - February 2014. 3045. Retrieved from https://scholarworks.umass.edu/theses/3045 This thesis is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Masters Theses 1911 - February 2014 by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. THE TAXONOMY OF THE SIDE SPECIES GROUP OF SPILOCHALCIS (HYMENOPTERA:CHALCIDIDAE) IN AMERICA NORTH OF MEXICO WITH BIOLOGICAL NOTES ON A REPRESENTATIVE SPECIES. A Thesis Presented By GARY JAMES COUCH Submitted to the Graduate School of the University of Massachusetts in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1984 Department of Entomology THE TAXONOMY OF THE SIDE SPECIES GROUP OF SPILOCHALCIS (HYMENOPTERA:CHALCIDIDAE) IN AMERICA NORTH OF MEXICO WITH BIOLOGICAL NOTES ON A REPRESENTATIVE SPECIES. A Thesis Presented By GARY JAMES COUCH Approved as to style and content by: Dr. T/M. Peter's, Chairperson of Committee CJZl- Dr. C-M. Yin, Membe D#. J.S. El kin ton, Member ii Dedication To: My mother who taught me that dreams are only worth the time and effort you devote to attaining them and my father for the values to base them on.
    [Show full text]
  • Surveying for Terrestrial Arthropods (Insects and Relatives) Occurring Within the Kahului Airport Environs, Maui, Hawai‘I: Synthesis Report
    Surveying for Terrestrial Arthropods (Insects and Relatives) Occurring within the Kahului Airport Environs, Maui, Hawai‘i: Synthesis Report Prepared by Francis G. Howarth, David J. Preston, and Richard Pyle Honolulu, Hawaii January 2012 Surveying for Terrestrial Arthropods (Insects and Relatives) Occurring within the Kahului Airport Environs, Maui, Hawai‘i: Synthesis Report Francis G. Howarth, David J. Preston, and Richard Pyle Hawaii Biological Survey Bishop Museum Honolulu, Hawai‘i 96817 USA Prepared for EKNA Services Inc. 615 Pi‘ikoi Street, Suite 300 Honolulu, Hawai‘i 96814 and State of Hawaii, Department of Transportation, Airports Division Bishop Museum Technical Report 58 Honolulu, Hawaii January 2012 Bishop Museum Press 1525 Bernice Street Honolulu, Hawai‘i Copyright 2012 Bishop Museum All Rights Reserved Printed in the United States of America ISSN 1085-455X Contribution No. 2012 001 to the Hawaii Biological Survey COVER Adult male Hawaiian long-horned wood-borer, Plagithmysus kahului, on its host plant Chenopodium oahuense. This species is endemic to lowland Maui and was discovered during the arthropod surveys. Photograph by Forest and Kim Starr, Makawao, Maui. Used with permission. Hawaii Biological Report on Monitoring Arthropods within Kahului Airport Environs, Synthesis TABLE OF CONTENTS Table of Contents …………….......................................................……………...........……………..…..….i. Executive Summary …….....................................................…………………...........……………..…..….1 Introduction ..................................................................………………………...........……………..…..….4
    [Show full text]
  • Toxicity of Insecticides and Miticides to Natural Enemies in Australian Grains: a Review
    insects Review Toxicity of Insecticides and Miticides to Natural Enemies in Australian Grains: A Review Kathy Overton 1,*, Ary A. Hoffmann 2 , Olivia L. Reynolds 1 and Paul A. Umina 1,2 1 Cesar Australia, 293 Royal Parade, Parkville, VIC 3052, Australia; [email protected] (O.L.R.); [email protected] (P.A.U.) 2 Pest and Environmental Adaptation Research Group, School of BioSciences, Bio21 Institute, The University of Melbourne, Parkville, VIC 3052, Australia; [email protected] * Correspondence: [email protected] Simple Summary: Controlling invertebrate pests in crop fields using chemicals has been the main management strategy within the Australian grains industry for decades. However, chemical use can have unintended effects on natural enemies, which can play a key role in suppressing and controlling pest outbreaks within crops. We undertook a literature review of studies that have conducted chemical toxicity testing against arthropod natural enemies relevant to the Australian grains industry to examine trends and highlight research gaps and priorities. Most toxicity trials have been conducted in the laboratory, with few at larger, and hence, industry-relevant scales. Researchers have used a variety of methods when conducting toxicity testing, making it difficult to compare within and across different species of natural enemies. Furthermore, we found many gaps in testing, leading to unknown toxicity effects for several key natural enemies, some of which are economically important predators and parasitoids. Through our review, we make several key recommendations for future areas of research that could arm farmers and their advisors with the knowledge they need to make informed decisions when it comes to controlling crop pests.
    [Show full text]
  • Plutella Xylostella (Lepidoptera: Plutellidae) Using Radiation-Induced Sterility
    XA0201546 Field trials in South China to control the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) using radiation-induced sterility R. Yang, D. Xia, W. Gu, Y. Zhang Institute for Application of Atomic Energy, Zheijang Academy of Agricultural Sciences, Hanzshou, China Abstract. This paper discusses the control of the diamondback moth, Plutella xylostella by the sterile insect technique (SIT). Our studies included mating characteristics, sterility of the Fi generation, dispersal and recapture of irradiated moths, as well as control of DBM using SIT and Fx sterility, and an economic evaluation of Fi sterility to protect cabbage. Male DBM mated an average of 16 times and female DBM mated an average of 4 times. However, irradiated male DBM only mated an average of 7.2 times. Seventy percent of matings occurred from 18:00-24:00 h with an average duration of 80 min. Irradiated male moths and untreated male moths exhibited the same attraction to female moths. After 10 days, most (94.2%) of the released, sterile DBM were recaptured within 40 m of the release site. Only one DBM was recaptured at 120 m from the release site. The area of dispersal was calculated to be 696 m2 during the first three days, hi a field study to control DBM by releases of irradiated insects, the ratio of sterile to wild DBM was 4.7:1. During this study, the egg sterility in the Fi and F2 generations was 79.0% and 81.7%, respectively. The developmental times for the Fi and F2 generations were 4 and 12 days longer, respectively, than for DBM in the control area.
    [Show full text]
  • Thesis Template
    TAXONOMY, DISTRIBUTION AND PEST STATUS OF PLUTELLA SPECIES (LEPIDOPTERA: PLUTELLIDAE) IN AUSTRALIA AND NEW ZEALAND Kariyawasam Haputhanthri Kankanamge Tharanga Niroshini Submitted in fulfilment of the requirements for the degree of Master of Applied Sciences (Research) School of Earth Environmental and Biological Sciences Science and Engineering Faculty Queensland University of Technology 2018 Keywords Adults, ANOVA, Bayesian analysis, CO1 barcode gene, crops, DNA, genitalia morphological features, host plant, larvae, light trap, maximum likelihood, measurements, PCR, phylogenetic analyses, Plutella australiana, Plutella xylostella, R statistical analyses, Sanger sequencing, taxonomy. i Abstract The diamondback moth (DBM), Plutella xylostella L. (Lepidoptera: Plutellidae), is the most destructive agricultural pest in the word causing damage to brassica crops such as cabbage, kale, broccoli, and cauliflower. Its global distribution, movement over long distances and rapid evolution of insecticide resistance make this a key pest of international importance. P. xylostella was introduced to Australia in 1882 and has become widely distributed in Australia. Despite reports of low levels of genetic variation in the Australian population (Endersby et al., 2006), more recent molecular studies indicated the presence of variants within the Australian Plutella population. A study of allozymes in P. xylostella populations from 14 locations worldwide included specimens from 5 different locations in Australia (Adelaide, Brisbane, North Queensland, Melbourne
    [Show full text]
  • Volatile DMNT Directly Protects Plants Against Plutella Xylostella By
    RESEARCH ARTICLE Volatile DMNT directly protects plants against Plutella xylostella by disrupting the peritrophic matrix barrier in insect midgut Chen Chen1†, Hongyi Chen1†, Shijie Huang1†, Taoshan Jiang1, Chuanhong Wang1, Zhen Tao1, Chen He1, Qingfeng Tang2, Peijin Li1* 1The National Key Engineering Lab of Crop Stress Resistance Breeding, the School of Life Sciences, Anhui Agricultural University, Hefei, China; 2Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, the School of Plant Protection, Anhui Agricultural University, Hefei, China Abstract Insect pests negatively affect crop quality and yield; identifying new methods to protect crops against insects therefore has important agricultural applications. Our analysis of transgenic Arabidopsis thaliana plants showed that overexpression of pentacyclic triterpene synthase 1, encoding the key biosynthetic enzyme for the natural plant product (3E)-4,8-dimethyl- 1,3,7-nonatriene (DMNT), led to a significant resistance against a major insect pest, Plutella xylostella. DMNT treatment severely damaged the peritrophic matrix (PM), a physical barrier isolating food and pathogens from the midgut wall cells. DMNT repressed the expression of PxMucin in midgut cells, and knocking down PxMucin resulted in PM rupture and P. xylostella death. A 16S RNA survey revealed that DMNT significantly disrupted midgut microbiota *For correspondence: populations and that midgut microbes were essential for DMNT-induced killing. Therefore, we [email protected] propose that the midgut microbiota assists DMNT in killing P. xylostella. These findings may †These authors contributed provide a novel approach for plant protection against P. xylostella. equally to this work Competing interests: The authors declare that no Introduction competing interests exist.
    [Show full text]
  • A Wasp Parasitoid, Diadegma Insulare (Cresson) (Insecta: Hymenotera: Ichneumonidae)1 Andrei Sourakov and Everett Mitchell2
    EENY-124 A Wasp Parasitoid, Diadegma insulare (Cresson) (Insecta: Hymenotera: Ichneumonidae)1 Andrei Sourakov and Everett Mitchell2 Distribution Description Diadegma insulare is found in the United States and South Egg America: New Hampshire west to southern British Colum- The egg is clear, and is hard to distinguish from the host’s bia, south to Florida, Texas, and California; Hawaii, West fat body when it is dissected. Unlike Cotesia plutella, Indies, and Mexico south to Venezuela. another parasitoid of the diamondback moth, the egg is rounded rather than pointed and lacks a projection. These wasps are found in cruciferous crops, overwintering as a cocoon. The number of generations per year cor- responds to the number of generations of its hosts: Hellula undalis (F.), Plutella armoracia Bsk., and P. xylostella (L.), the diamondback moth. Figure 2. Egg of Diadegma insulare (Cresson), a parasitoid wasp. Figure 1. Male Diadegma insulare (Cresson), a parasitoid wasp, and Credits: Guangye Hu , USDA mature larvae of the diamondback moth, Plutella xylostella (Linnaeus). Credits: Andrei Sourakov, Florida Museum of Natural History 1. This document is EENY-124, one of a series of the Department of Entomology and Nematology, UF/IFAS Extension. Original publication date March 2000. Revised November 2005. Reviewed May 2020. Visit the EDIS website at https://edis.ifas.ufl.edu. This document is also available on the Featured Creatures website at http://entnemdept.ifas.ufl.edu/creatures/. 2. Andrei Sourakov, Florida Museum of Natural History; and Everett Mitchell, USDA, Gainesville, FL. The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations.
    [Show full text]