GEM as a source for disease and insect resistance & Crop Biosecurity

1. GEM as a source for disease and insect resistance & Crop Biosecurity Wm. E. Dolezal Pioneer Hi-Bred International, Inc. Johnston, IA GEM Cooperator Meeting - 2003 Hyatt Regency Hotel Chicago, IL December 10, 2003

2. 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

3. 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 • 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

4. 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. Importance of Maize Genetic Resources in Crop Biosecurity Unintentional Pest Introduction through Worldwide Trade Example: CRW introduction into Europe

5. Importance of Maize Genetic Resources in Crop Biosecurity Are we operating our plant breeding programs under an outdated model of genetic susceptibility to a new series of Exotic PESTS and higher introduction risk?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)

6. Countries • Argentina, Thailand, USA 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)

7. Identifying Worldwide Disease Screening Locations - GEM DISEASE NAME GEM Collaborator Northern Leaf Blight: PHI, Northern Leaf Spot Professional Seed Southern Leaf Blight: Prof. Seed, PHI, NCSU Southern Rust: PHI Eyespot: Prof. Seed Common Rust: PHI Tropical Rust: --- Stewart’s Wilt: Prof. Seed Goss’ Wilt: --- Gray Leaf Spot: Prof. Seed, NCSU, OSU Head Smut: --- Common Smut: --- Corn Stunt Spiroplasma: --- MDMV: --- MDMCPX: OSU? HPV: --- MRDV/MRFV: Nidera, PHI Maize Stripe Virus: --- CLN: --- SHANE SCOTT 021397

8. Identifying Worldwide Disease & Insect Screening Locations - GEM DISEASE/INSECT NAME GEM Collaborator Bacterial Stalk Rot --- Sorghum Downy Mildew (S.macro.) --- Philippine Downy Mildew (S. phil.): AgriSource Diplodia Stalk Rot: --- Anthracnose Stalk Rot: Cornell, Univ.-Del Fusarium 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,MS Fumonisin Univ-IL,USDA-ARS-NC DON --- Insects: CEW Texas A&M CRW PHI, Univ. IL, USDA-ARS-Mo ECB PHI, Univ-IL SWCB USDA-ARS-MS SHANE SCOTT 021397

10. GEM as a “target rich” source for identifying new sources of resistance to major crop performance traits Stalk Lodging – Premature death and standability

11. Solicit New Members/Cooperators? • Public • Agricultural Universities. • NGO Research Centers / CGIAR • Government Agricultural Research Units • Multinational Maize Breeding Companies • Additional Opportunities to enlist other Worldwide Collaborators • Proactive effort by USDA-APHIS • Collect pest information before before pest arrival • Africa • Asia • Central & South America

12. 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

13. Southern Corn Rust (Puccinia polysora) Central Brazil – March 2003 Susceptible hybrid – foreground Resistant 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?

14. 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

15. 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

16. 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

17. Insure that a well developed ear has formed when collecting late season traits (foliar, ears & stalk traits) Data collected from GEM Screening locations Top Quality • Insure adequate disease & insect pressure • measure against an appropriate • maturity & trait check (B73, SX19, etc). • be aware of gene insertions (B73Ht1)

18. Other Testing Complications:Sensitivity to common herbicides 2003 Herbicide Damage Johnston, IA North Carolina • GEM Cooperators: Earlier generation screening for lethals? • Systematic screening of common herbicide chemistry? • Compiling data on any reports of injury?

19. Cuba164:S1517-163-1-B • Ramosa gene? • Displayed both at • Johnston, IA • Woodland, CA Both locations experienced heat and drought stress

20. 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?

21. SHANE SCOTT 1/97 Thank you for this opportunity to participate & for your attention!