GEM as a source for disease and insect resistance & Crop Biosecurity Wm. E. Dolezal Pioneer Hi-Bred International, Inc. Johnston, IA GEM Cooperator Meeting.

GEM as a source for disease and insect resistance

& Crop Biosecurity

Wm. E. DolezalPioneer Hi-Bred International, Inc.

Johnston, IA

GEM Cooperator Meeting - 2003Hyatt Regency Hotel

Chicago, ILDecember 10, 2003

Topics to discuss today

• Importance of Maize Genetic Resources in Crop Biosecurity

• Need to identify new source for disease and insect resistance

• Screening/pathogen population monitoring opportunities worldwide

• The difficulty in screening material that is not crossed onto a locally adapted tester

• Suggestions in the use of these GEM germplasm in breeding programs

Importance of Maize Genetic Resources in Crop Biosecurity

The events of September 11, 2001 has changed our world.• What was not considered possible is now plausible

• Economic disruption – crop bioterroristic targets – Corn & soybean?• Relatively “low tech” effort needed.• Historical efforts during the cold war by the super powers

Are we broad enough with our genetic diversity of our major commercial maize germplasm?

Stiff Stalk X Non-Stiff Stalk (Lancaster, Etc)

Importance of Maize Genetic Resources in Crop Biosecurity

Unintentional Pest Introduction through Worldwide Trade

Once major natural barriers to pest movement now easily

overcome by modern transportation

Unintentional Pest Introductions through man’s activities:• Since 1980, over 200+ Non-indigenous species have been intercepted by the USDA. 59 economically damaging.

• Free Trade agreements have allowed more INTERNATIONAL movements of commodities and containerized freight shipments.

Example: CRW introduction into Europe

Importance of Maize Genetic Resources in Crop Biosecurity

Are we operating ourplant breeding programs under an outdated model

of genetic susceptibility to a new series of Exotic PESTS and higher introduction risk?

Some Recent Examples:• Soybean Rust • Soybean Aphid• Russian Wheat Aphid• Sorghum Ergot• Corn Rootworm (Europe)

Microsoft PowerPoint Presentation

Need to identify new source of insect & disease resistance

Summary GEM Disease/Entomology Collaborations - 2003

18 Collaborations• 4 Private Companies: AgriSource, Nidera, Pioneer, (All In Kind Support) & Professional Seed

• 7 Universities (SCA’s): Cornell, LSU, NCSU, Ohio St. Univ.Texas A& M(2), Univ’s of DE & IL

• 6 USDA-ARS GA, MO, MS(2), & NC(2) (USDA Support)

Countries• Argentina, Thailand, USA

SHANE SCOTT 021397

Identifying Worldwide Disease Screening Locations - GEM

DISEASE NAME GEM Collaborator Northern Leaf Blight: PHI, Northern Leaf Spot Professional SeedSouthern Leaf Blight: Prof. Seed, PHI, NCSUSouthern Rust: PHIEyespot: Prof. Seed Common Rust: PHITropical Rust: ---Stewart’s Wilt: Prof. SeedGoss’ Wilt: ---Gray Leaf Spot: Prof. Seed, NCSU, OSUHead Smut: ---Common Smut: ---Corn Stunt Spiroplasma: ---MDMV: ---MDMCPX: OSU?HPV: ---MRDV/MRFV: Nidera, PHIMaize Stripe Virus: ---CLN: ---

SHANE SCOTT 021397

Identifying Worldwide Disease & Insect Screening Locations

- GEMDISEASE/INSECT NAME GEM Collaborator

Bacterial Stalk Rot ---Sorghum Downy Mildew (S.macro.) ---Philippine Downy Mildew (S. phil.): AgriSourceDiplodia Stalk Rot: ---Anthracnose Stalk Rot: Cornell, Univ.-DelFusarium Stalk Rot: ---Gibberella Stalk Rot: ---Diplodia (D. maidis) Ear Rot: PHI,Diplodia (D. macrospora): ---Fusarium Ear Rot: PHI, NCSU,Gibberella Ear Rot: ---

Mycotoxins: Aflatoxin LSU, Texas A&M,

USDA-ARS-GA,MSFumonisin Univ-IL,USDA-ARS-NC DON ---

Insects:CEW Texas A&MCRW PHI, Univ. IL, USDA-ARS-MoECB PHI, Univ-ILSWCB USDA-ARS-MS

GEM as a “target rich” source for identifying new sources of resistance to major crop performance traits

Stalk Lodging – Premature death and standability

Additional Opportunities to enlist other Worldwide CollaboratorsProactive effort by USDA-APHIS Collect pest information before before pest arrival

• Africa • Asia• Central & South America

Solicit New Members/Cooperators?

• Public

• Agricultural Universities.

• NGO Research Centers / CGIAR

• Government Agricultural Research Units

• Multinational Maize Breeding Companies

Screening/pathogen population Monitoring opportunities worldwide

Team Involvement of Pathologist / Entomologist, working with Plant Breeders, to Understand Pest Population Biology

• Determine stability of host resistance by understanding the existing variability in pest population

• Northern leaf blight genes: HT1-3 genes• Anthracnose – MP305, LB31, exotic• Rust genes – Rp1’s, Rpp’s, • Ear molds & mycotoxin production

• Linkages with maize genomic programs

Southern Corn Rust (Puccinia polysora)

Central Brazil – March 2003

Susceptible hybrid – foregroundResistant hybrid - background

What is our current ability to determine races using host differentials?

• A. Roberts (1963) rust collection & host differential sets are mostly gone!

• Rpp9 gene in use but not effective in parts of So. America, Asia and SE USA

• What are the identity of the other races in these regions?• Are specific sources of resistance identified for each race or are there partial resistance sources available?

GEM Collaborators Span the World

Offers unique opportunity for characterizing material study plant pathogen populations

and discover resistant/tolerant germplasm

Example: Race, strain or biotype differentiation • Puccinia polysora

• Asian, So. American & USA isolates

• Maize Rio Cuarto Virus / Maize Rough Dwarf Virus

Yield without yield stability (disease/insect resistance) It is just as bad!

•Big Advantage of GEM – Yield is a major selection component

• Must avoid the “Greeny Winnies”

• Resistance without yield is NOT a winner!

• Balance: ear size (yield) & pest resistance

Microsoft PowerPoint Presentation

The difficulty in screening material that is not crossed onto a locally adapted tester

Difficult to measure assigned disease/insect trait when you have poor plant development due to choice of non - adapted tester.

Makes the job much more difficult to utilize other worldwide screening locations to test GEM material.

• cross onto adapted tester that is good for other key agronomic traits but poor for the trait of interest

Top Quality

Data collected from GEM Screening locations

Insure adequate disease & insect pressure• measure against an appropriate maturity & trait check (B73, SX19, etc).

• be aware of gene insertions (B73Ht1)

Insure that a well developed ear has formed when collecting late season traits (foliar, ears & stalk traits)

Other Testing Complications:Sensitivity to common herbicides

GEM Cooperators: Earlier generation screening for lethals?• Systematic screening of common herbicide chemistry? • Compiling data on any reports of injury?

2003 Herbicide DamageJohnston, IA

North Carolina

Cuba164:S1517-163-1-B

Ramosa gene?

Displayed both at• Johnston, IA• Woodland, CA

Both locations experienced heat

and drought stress

Suggestions in the use of these GEM germplasm in breeding programs

• Making GEM cross onto locally adapted tester that is resistant/tolerant to most diseases but susceptible to specific trait

• Other suggestions?

Thank you for this opportunity to participate & for your attention!

SHANE SCOTT 1/97