Parasitoids by yantingting

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									 Dennise Medina
Arelys Rodriguez
 Has everyone heard of a parasite?
 What is a parasite?
 Has anyone heard of a parasitoid?
 What is a parasitoid?
 The term Parasitoid often becomes confused
  with the term Parasite
 An  organism that lives in a symbiotic
  relationship with a phylogenetically
  unrelated organism over a prolonged
  period of time
 A Parasite lives in or on its host
 It obtains nourishment from its host
 Parasites cannot live independently
 Relationship lasts the lifetime of the host
A  parasitoid is an organism that spends a
  significant portion of its life history attached
  to or within a single host organism
 A parasitoid ultimately kills and often
  consumes its host in the process
 Parasitoids obtain nourishment from host,
  but is not needed to survive
 Parasitoids can live independently
 Relationship lasts the life cycle of its host
 Parasitoids are similar to typical parasites
  except in the certain fate of the host
 In a typical parasitic relationship, the parasite
  and host live side by side without lethal damage
  to the host
 The parasite takes enough nutrients to thrive
  without preventing the host from reproducing
 Parasitoids differ from parasites in their
  relationship with the host
 In a parasitoid relationship, the host is usually
  killed after the full development of the other
  organism
 The host usually dies before it can reproduce
 Thistype of relationship seems to occur only
 in organisms that have fast reproduction
 rates
     Such as insects
     Such as mites
 Parasitoidsare also often closely coevolved
 with their hosts
 Most biologists use the term parasitoids to
  refer only to insects with this type of life
  history
 Some argue the term should be used more
  exclusively to include:
     parasitic nematodes
     seed weevils
     certain bacteria
     Certain viruses (e.g. bacteriophages)
         Due to the fact that they destroy their host
 Idiobiont
 Koinobiont
    Endoparasitoids
    Ectoparasitoids
 Hyperparasite




                       Great Potter Wasp (Delta unguiculata)
 Idiobiont parasitoids are
  those which prevent any
  further development of the
  host after initial
  parasitization
 The host’s life stage would
  be immobile
     An egg
     A pupa

   Almost without exception,
    they live outside the host
                                 Stephanoidea
   Koinobiont parasitoids allow the host to continue its
    development
   Often do not kill or consume the host until:
     The host is about to either pupate
     The host becomes an adult
   This typically involves living within an active, mobile host
 Thereare two types of Koinobiont
 Parasitoids
     Endoparasitoids
     Ectoparasitoids




 Adult Bathyplectes anurus, a parasitoid of alfalfa weevil larvae
 Koinobiont  parasitoids develop completely
 inside of their prey




         Endoparasitoid Ageniaspis citricola
Female Eriborus terebrans a larval endoparasitoid of the European corn borer
Photographs depicting the various life stages of Spodoptera littoralis
       and the larval endoparasitoid Cotesia marginiventris
 Koinobiont parasitoids develop outside the host body
 They are frequently attached or embedded in the host's
  tissues




    An egg of the wasp parasitoid Larra bicolor Fabricius deposited on the ventral side of the
        thorax of a mole cricket. The elongate, pearly white egg is central in the picture.
 Itis common for a parasitoid to itself serve
  as the host for another parasitoid's offspring
 This type of parasitoid is termed a
  hyperparasite
      Biologists believe it is slightly misleading, as both
       the host and the primary parasitoid are killed
A  better term is secondary parasitoid, or
  hyperparasitoid
 Most such species known are in the insect
  order Hymenoptera
Male ichneumonid wasp Mesostenus thoracicus. Parasitoid of
Herpetogramma and hyperparasitoid of Alabagrus.
   About 10% of described insect species are parasitoids
   Below are four groups of parasitoids:
   Hymenoptera
     Chalcid wasps (family Chalcidae)
     Ichneumon wasps (family Ichneumonidae)
   Diptera
       Tachinid flies (family Tachinidae)
   Strepsiptera
       Stylopid flies (family Stylopidae)




                                             Male Diadegma insulare (Cresson)
   The distribution of the
    larval habits given in the
    box were optimized onto
    the phylogeny
       such as insects
   This evolution of larval
    feeding modes tends to
    occur sporadically among
    those groups containing
    both:
       Parasitic Phytophagous
        Lineages
       Secondarily Phytophagous
        Lineages
Male specimen of Denaeostephanus sulcatus (Aguiar et Janzen),
 included in Baltic amber, one of ancient specimen of parasitoid
 Adult parasitoids are free-living and may
  be predaceous
 Most insect parasitoids only attack a
  particular life stage of one or several
  related species
 The immature parasitoid develops on or
  within a pest, feeding on body fluids and
  organs, eventually leaving the host to
  pupate or emerging as an adult
 The life cycle of the pest and parasitoid
  can coincide, or that of the pest may be
  altered by the parasitoid to accommodate
  its development
   In some species, only one parasitoid will
    develop in or on each pest while
   In others, hundreds of young larvae may
    develop within the pest host
   Female parasitoids may also kill many pests
    by direct feeding on the pest eggs and
    immatures




Pre-pupa of diamondback moth, Plutella xylostella
         (Linnaeus), inside the cocoon              Wasp Larvae
 Specialized  in their choice of host
 They are smaller than host
 Only the female searches for host
 Different parasitoid species can attack
  different life stages of host
 Adults are free-living, mobile, and may be
  predaceous
 Eggs or larvae are usually laid in, on, or
  near host
 Immatures remain on or in host
 Immatures almost always kill host
Egg
Larva
Pupa
Adult
 Common    Name: Wasp Parasitoid
 Scientific name: Meteorus autographae
    Class: Insecta
        Order: Hymenoptera
          Family: Braconidae




                                Adult Male, Wasp Parasitoid
 The  egg is clear and
  thin-walled
 Soon after
  oviposition, the
  folded-in-two larva
  can be observed
  inside



                          Egg, Wasp Parasitoid
 The larva is translucent, long and slender, with a
  pronounced sclerotized head
 Often, more than one egg is laid, but the first
  larva to emerge kills its siblings




    Larva Before         Larva After Pupation
      Pupation
 The brown-colored, 5 mm-long cocoon is
  usually suspended from the edge of the leaf
  on a silk string (Actually a Cocoon)




Pupa, Wasp Parasitoid   Cocoon, Wasp Parasitoid
Cocoon of braconid wasp parasitoid Alabagrus texanus
 The adult wasp is orange, with black eyes
  and antennae
 The body does not exceed 6 mm
 The female has a well-defined black
  ovipositor




        Adult Female          Adult Male
 Several studies have shown that parasitoids
  and predators can be efficient biological
  control agents against the different grape
  berry moths
 As much as 50–60% of the moth larvae can be
  naturally controlled (Luciano et al., 1988; Coscolla, 1997; Thiéry
  et al., 2001; Bagnoli and Lucchi, 2005; Thiéry et al., 2006).
 M.autographae was found to be an
 important control agent of soybean looper
     Up to 24% of this pest's larvae were found to
      be parasitized in South Carolina
 InFlorida, it was found emerging from
  cabbage looper larvae
 Many other species of noctuids were
  found to be a suitable host
     All larval instars were parasitized
 Manyother cabbage looper control agents
 (Cotesia marginiventris) attack only
 young larvae
     This limits their effectiveness in control of
      these pests
1.   Superparasitism in mass reared Ashmead
2.   Attraction of Dibrachys cavus to its Host
     Frass
3.   The Biology of Bracon celer as a parasitoid
     of the olive fruit fly
4.   Impact of Host Feeding on Size of Progeny
5.   Whether Host Size Equal to Host Quality
 Superparasitism   frequency and its effects on
  the quality of mass-reared Diachasmimorpha
  longicaudata (Ashmead) parasitoids were
  investigated under laboratory conditions
 Hypothesis: Superparasitism in D.
  longicaudata might be adaptive
 Superparasitism: The oviposition behavior of
  female parasitoids when they lay their eggs
  in a host that is already parasitized
 To determine the frequency and prevalence of
  superparasitism under mass rearing conditions
 To evaluate the effects of different levels of
  superparasitism on:
    Main quality control of parasitoids
    Performance parameters of parasitoids
   discuss the implications of this phenomenon
 To
 under the mass rearing context
 Percentage     of adult emergence
 Sex ratio
 Survival
 Fecundity
 Flight ability of adult parasitoids




An ichneumonid parasitoid wasp, Coleocentrus incertus ASHMEAD
 Ashmead   has become the most commonly employed
  biological control agent against fruit flies worldwide
 Has a high capacity to adapt to different
  environments
 Can achieve higher levels of parasitism than other
  parasitoids
 Efficient methods for mass rearing and augmentative
  releases have been developed in several parts of the
  world
 In Mexico, this parasitoid is being mass reared at the
  Moscafrut facility located at Metapa de Dominguez,
  Chiapas, and released in different parts of the
  country
 Over  92% of the sampled pupae had more than
  one scar, indication of superparasitism
 Individuals developing in pupae with moderate
  levels of superparasitism (2-6 scars per pupa):
  Experienced lower mortality
  Had better flight ability
  Showed the highest percentage of emergence
 Superparasitism represents a conditional
  strategy that increases the reproductive success
  in this species
 Hypothesis:  Parasitoid Dibrachys cavus
  uses the larval frass in search of its host
   Frass: Excrement or debris left by insect
    larva
 Goal of our study: To determine which
  components of the host odor attract D.
  cavus from a distance
 The specificity of this attraction and
  whether it varied according to the larval
  food plant was tested
1.        The response of D. cavus females to the
          following were tested:
     1.    to host larvae without frass
     2.    to silk
     3.    to frass alone
     4.    whether it discriminated among different host
           species on the basis of their odor
2.        The influence of the following for
          attractiveness were tested:
     1.    host larval food
     2.    Host frass
Atwo-armed olfactometer was used to
 measure the attractiveness of:
     L. botrana larvae
     L. botrana silk
     L. botrana frass
 after larvae were fed on different host plants
 Frass of two orders of Class Insecta assayed:
     L. botrana (Order Lepidoptera)
     Eupoecillia ambiguella (Order Lepidoptera)
     Sphinx ligustri (Order Lepidoptera)
     Chorthippus brunneus (Orthoptera)
 Larval food of L. botrana did not modify frass
  attractiveness, but that the moth species did
 D. cavus was attracted to frass produced by
  three species of Lepidoptera, but not by
  larvae alone
 D. cavus was not attracted to the silk
  produced by L. botrana larvae
 Larval food did not modify frass
  attractiveness, but that the moth species did
 Bracon   Celer is the parasitoid of the olive
  fruit fly
 B. Celer is the most abundant parasitoid
  attacking the olive fly, Bactrocera oleae in
  commercial and wild olives in the fly’s native
  range in South Africa and Kenya
 B. celer parasitizes at levels as high as 87% in
  South African olive orchards
 Results are based on:
     Insectary production methods
     The potential use of B. celer as a biological
      control agent for the olive fly in California
 Female B. celer preferentially probe and oviposit
  into olives containing late third-instar fly larvae
 The parasitoid develops as a solitary,
  ectoparasitic idiobiont
 The mean longevity of adult female wasps when
  provided honey and water was significantly
  greater than when they were provided water
  alone, or nothing
 Fruit quality influences oviposition decisions by
  B. celer, either through:
   Volatile production
   Tactile cues
 25  female wasps were observed under low
  and high humidity levels
 Is host feeding influenced by the level of
  humidity experienced by wasps?
 Female wasps had no access to water.
 Parasitized eggs were incubated
 Parasitized eggs were classified as:
    host fed
    or not host fed
 One  hind tibia of each individual emerging
  from the eggs was measured
 The number of eggs
 Longevity of resulting progeny
 Size of the spawned progeny
 The male wasps were significantly larger
  than the female wasps
 Especially when host feeding did not occur




           A wasp parasitoid of stink bug eggs
  Two    different strains of host caterpillars
       C. pomonella
       C. molesta
  Were  offered to female wasps in a glass vial
  Eggs and larvae were studied under a
   microscope
  The results of the offspring were examined




C. Pomonella Cocoon
 Host handling time
 Probing time
 Egg deposition to egg hatching time
 Larval development time
 Brood time
 Pupal stage
 Number of average offspring
 Amount of eggs laid in a lifetime
 Offspring size increased with host size for C.
  molesta hosts
 Clutch size increased with host size on C.
  pomonella
 Factors that influenced parasitoid offsprings’
  number and size:
     Nutrient convertibility
     Quality
     Quantity of host tissue
 Host species DO
  NOT affect the
  reproductive
  success of the
  parasitoid
 Host size is NOT
  equal to host
  quality
 Dennise Medina
Arelys Rodriguez

								
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