GEM as a source for disease and insect resistance & Crop Biosecurity Wm. E. Dolezal Pioneer Hi-Bred International, Inc. Johnston, IA GEM Cooperator Meeting Hyatt Regency Hotel Chicago, IL December 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Importance of Maize Genetic Resources in Crop Biosecurity Are we operating our plant breeding programs under an outdated model of genetic susceptibility to a new series of Exotic PESTS and higher introduction risk?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)

Need to identify new source of insect & disease resistance Summary GEM Disease/Entomology Collaborations 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-ARSGA, MO, MS(2), & NC(2) (USDA Support) Countries Argentina, Thailand, USA

SHANE SCOTT Identifying Worldwide Disease Screening Locations - GEM DISEASE NAMEGEM Collaborator Northern Leaf Blight: PHI, Northern Leaf SpotProfessional 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 Identifying Worldwide Disease & Insect Screening Locations - GEM DISEASE/INSECT NAMEGEM 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: AflatoxinLSU, Texas A&M, USDA-ARS-GA,MS FumonisinUniv-IL,USDA-ARS-NC DON--- Insects: CEWTexas A&M CRWPHI, Univ. IL, USDA-ARS-Mo ECBPHI, Univ-IL SWCBUSDA-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 Collaborators Proactive 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 – 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?

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

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 Damage Johnston, IA North Carolina

Cuba164:S 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