title: Evidence of superclones in Australian cotton aphid Aphis gossypii Glover (Aphididae: Hemiptera).
abstract: BACKGROUND
  Aphis gossypii is an important pest of cotton that has developed resistance to many chemicals used for its control. Any lack of understanding of its genetic structure, resistance status and host plant specialisation hampers effective management.
  
  
  RESULTS
  Eight microsatellite markers were genotyped for a collection of Australian A. gossypii field isolates from 55 plant species from major Australian cotton-producing regions. The aphid's pirimicarb resistance status linked to the ACE1 (acetylcholinesterase) S431F mutation was determined by PCR-RFLP. Overall, the genetic diversity was low and there were only 13 multilocus genotype (MLG) groups found in a total of 936 aphids, suggesting asexual reproduction. Three MLGs (Aust-01, Aust-02 and Aust-04) represented 78% of all aphids tested. MLGs Aust-01 (41%) and Aust-02 (18%) were linked to the ACE1 S431F mutation and found on cotton and a range of hosts. Aust-04 (19%) hosted mainly on cotton (but also Asteraceae and Malvaceae) was predominantly susceptible to pirimicarb. Given their abundance and widespread occurrence, these three clones were considered to be superclones.
  
  
  CONCLUSIONS
  The study demonstrated that any strategy to control A. gossypii and manage pirimicarb resistance should target A. gossypii strains of all MLG types residing on any plant species and not just cotton
authors.affiliation: NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Narellan, NSW 2567, Australia. yizhou.chen@.dpi.nsw.gov.au
authors.forename: Yizhou
authors.initials: Y
authors.lastname: Chen
authors.forename: Flavie
authors.initials: F
authors.lastname: Vanlerberghe-Masutti
authors.forename: Lewis J
authors.initials: LJ
authors.lastname: Wilson
authors.forename: Idris
authors.initials: I
authors.lastname: Barchia
authors.forename: Martin O
authors.initials: MO
authors.lastname: McLoon
authors.forename: Tanya
authors.initials: T
authors.lastname: Smith
authors.forename: Grant A
authors.initials: GA
authors.lastname: Herron
mesh_terms: D000110:Acetylcholinesterase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001042:Aphids / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics*; D001315:Australia; D002219:Carbamates / Q000494:pharmacology; D014644:Genetic Variation; D003368:Gossypium / Q000469:parasitology*; D019476:Insect Proteins / Q000235:genetics; D007305:Insecticide Resistance; D007306:Insecticides / Q000494:pharmacology*; D018895:Microsatellite Repeats; D009154:Mutation; D010935:Plant Diseases / Q000469:parasitology*; D011743:Pyrimidines / Q000494:pharmacology
chemical_list: D002219:Carbamates; D019476:Insect Proteins; D007306:Insecticides; D011743:Pyrimidines; C011994:pirimicarb; D000110:Acetylcholinesterase
keywords: Aphis gossypii; cotton; host races; insecticide resistance; population structure