Understanding resistance to cabbage seedpod weevil in yellow mustard
Download
1 / 21

Understanding resistance to cabbage seedpod weevil in yellow mustard xcanola hybrids - PowerPoint PPT Presentation


  • 113 Views
  • Uploaded on

Understanding resistance to cabbage seedpod weevil in yellow mustard x canola hybrids. Sanford Eigenbrode Plant , Soil and Entomological Sciences University of Idaho, Moscow, 83844- 2339 [email protected] Idaho Oilseed Conference 12 Feb 2009. Insect pests in canola.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Understanding resistance to cabbage seedpod weevil in yellow mustard xcanola hybrids' - caron


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Slide1 l.jpg

Understanding resistance to cabbage seedpod weevil in yellow mustard xcanola hybrids

Sanford Eigenbrode

Plant, Soil and Entomological Sciences

University of Idaho, Moscow, 83844-2339

[email protected]

Idaho Oilseed Conference

12 Feb 2009


Insect pests in canola l.jpg
Insect mustard pests in canola

  • 10% - 40% yield reductions from all insects.

  • One persistent insect problem is the cabbage seed pod weevil (CSPW)

  • A crucifer specialist

  • Can reduce rapeseed yields up to 35% (McCaffrey et al., 1986)

Ceutorhynchusobstrictus

CSPW



Mustard l.jpg
Mustard mustard

  • Condiment yellow mustard, Sinapis alba

  • High glucosinolate concentrations

  • Resistant or tolerant to most insects

Sinapis alba

A ‘non-host’ for CSPW


Mustard6 l.jpg
Mustard mustard

Two approaches

  • Breed for oilseed quality mustard that retains resistance

  • Introduce resistance from yellow condiment mustard into B. napususing interspecific crossing


Mustard7 l.jpg
Mustard mustard

Two approaches

  • Breed for oilseed quality mustard that retains resistance

  • Introduce resistance from yellow condiment mustard into B. napususing interspecific crossing


Slide8 l.jpg

Canola mustard x yellow mustardhybrids

cross-pollination between S. alba and B. napus followed by a combination of ovule culture and embryo rescue (Brown et al., 1997)

X


Slide9 l.jpg

Parental mustard Species

Glucosinolate Profiles (μmol/g)


Slide10 l.jpg

Hybrid mustard Glucosinolate Profile

R = ‘Resistant’ to CSPW

= eggs 17% to 25% of control

S

R

R

R

S = ‘Susceptible’ to CSPW

= eggs 40 to 70% of control

µmol/g

S

Ross et al. 2003

R

S


Conclusions from prior work l.jpg
Conclusions from prior work mustard

  • Resistance varies widely in S. alba x B. napus hybrids

  • The best lines tested so far are not as resistant as the resistant parent, S. alba

  • The mechanism is unknown, but appears to be unrelated to glucosinolate profiles


Objectives of this project l.jpg
Objectives of this project mustard

  • Screen additional interspecific hybrids, seeking additional hybrids resistant to oviposition by CSPW

  • Having identified resistant hybrids

    • Employ detailed behavioral bioassay to ascertain weevil responses

    • Conduct a wider survey of metabolites potentially responsible for resistance

    • Characterize pod morphology


Screen canister choice tests l.jpg
Screen: Canister mustard Choice Tests

  • 25 entries:

    • 5 parents + 20 hybrids

  • choice test:

    • each entry against Cyclone

    • excised ripe pods placed in cages with 1 ovipositing female weevil.

    • Count punctures, oviposition holes, eggs deposited (by dissection)

    • N = 10

Canisters for insect choice tests


Canister choice tests l.jpg
Canister Choice Tests mustard

After 1 day ofoviposition:

dissect under a light microscope

Count feeding punctures and eggs.

Cabbage Seedpod Weevil Eggs


Observations l.jpg
Observations mustard

  • Selected lines, based on resistance and phenotype will be tested in no-choice setting

  • Individual ovipositing female weevils will be observed continuously for 1 hour

  • Behavior on susceptible and resistant types compared for number of events and time spent engaged in:

    • Pod exploration

    • Preliminary feeding

    • Egg cavity formation

    • Turning

    • Ovipositing

    • Retracting

    • Pod brushing

      Following Kozlowski et al. (1983)


Observations16 l.jpg
Observations mustard

  • Resistant and susceptible reactions will be compared statistically

  • Noldus ‘Observer’ behavioral software

  • Key behaviors correlated with different types of resistance will be noted

  • N = 40 individual weevils x 8 selected lines


Characterization l.jpg
Characterization mustard

  • Measure pod size, toughness, hairiness and correlate these features with observed resistance.

  • Conduct a broad metabolic screen of the most resistant pod tissues to identify chemical profiles other than glucosinolates that could confer resistance.


Chemical characterization l.jpg
Chemical characterization mustard

  • Ongoing project on host relationships of Ceutorhynchuscardaria(hoary cress biological control)

  • Employs metabolic profiling (≈ 200 metabolites included).

  • Samples of most promising S. alba x B. napus hybrids can be included.


Years 1 and 2 l.jpg
Years 1 and 2 mustard

  • Year 1

    • bioassay, focus on the initial screening using choice tests (using live collected weevils)

    • characterize pod material morphologically and chemically (winter)

  • Year 2

    • bioassay, focus on direct observational studies (live collected weevils)

    • Select lines for additional development


Slide20 l.jpg

  • Special notes mustard

  • Project initiated by Joe McCaffrey (UI Entomology)

  • Long experience and expertise includes CSPW and other pests of oilseed Brassicacrops

  • My credentials for this project

  • M.S. and Ph.D. on aspects of Brassica entomology

  • Background in Host Plant Resistance to insects

  • Expertise in chemical ecology, plant defenses, glucosinolates

  • Veteran collaborator with Jack Brown


Questions l.jpg
Questions ? mustard


ad