Tree Breeding for Forest Health Current Successes

Transcription

1 Tree Breeding for Forest Health Current Successes How can Biotechnology Help? Richard A. Sniezko USDA Forest Service Dorena Genetic Resource Center Cottage Grove, OR Western white pine & White pine blister rust Port-Orford-cedar & Phytophthora lateralis

2 Information Brief Requested Overview: my work in breeding trees to address forest health concerns What gaps, if any, exist in traditional breeding that may be addressed by biotechnology What are the logistics of apply biotechnology tools in the content of tree breeding

3 Invasion Phytophthora austrocedrae CLIMATE CHANGE Chestnut blight Rapid ohia death White pine blister rust Phytophthora cinnamomi 1000 canker disease Sudden oak death WHO ARE YOU GOING CALL? USDA Forest Service -Genetics & FHP & partners Solution Healthy Dec 12, 2017 webinar

4 Saving the Forests ACTION NEEDED! Exclude new pests or pathogens! Confine spread or eradicate Biocontrol Silvicultural management Harness Genetic Resistance Restoration/Reforestation needed Early detection Rapid Response more tools needed! Healthy Dec 12, 2017 webinar

5 Envision the Future How to help shape the future for society? Do nothing Do something Genetics is the key or Dying forest Healthy forest

6 GOAL Want trees to be on the landscape for 100 s of years And be progenitors of future generations Don t want start massive restoration effort with temporary resistance (e.g., any non-durable major gene resistances) Use all available types of resistance

7 Using Genetics for Forest Health - The road to success Research Reforestation or Restoration SUCCESS Tree Improvement Management Commitment over Time Time Successful program takes several components all must be present Partnerships, public support and time also essential Continuity essential long-term commitments can be vital

8 BACKGROUND 26 years* in Applied/Operational Development of Resistance - For Restoration or Reforestation EXISTING PROGRAMS WHITE PINE BLISTER RUST 8 western N.A. species of 5-needle ( white ) pines WWP & SP since 1991 PHYTOPHTHORA ROOT DISEASE Port-Orford-cedar (since ~1993, designed/initiated operational program in 1997) KOA WILT koa (designed/initiated in 2003) POSSIBLE NEW PROGRAMS? Sudden oak death (SOD) tanoak Rapid Ōhi a death (ROD) - Ōhi a *Dorena GRC program has been active for 51 years Healthy Dec 12, 2017 webinar 7

9 Solution: GENETIC RESISTANCE Green, natural solution to a disease problem Is there genetic resistance? Is there tolerance? Resistance vs. tolerance What types and levels of resistance are available? What level is needed? What level is achievable? Correlations with other adaptive traits? Impacts of climate change on resistance? Is it durable resistance? Tree Improvement producing seed

10 RESISTANCE: North American Examples Major Gene Resistance Sugar pine* (Kinloch) Western white pine* (Barnes/Sniezko/Kinloch) Southwestern white pine & limber pine (Kinloch/Sniezko) Port-Orford-cedar (Sniezko) Quantitative Resistance (partial resistance) All 9 N.A. white pine species? (Hoff/Sniezko/Kinloch ) Port-Orford-cedar (Sniezko) Other/unknown Koa (Dudley/Sniezko) R.Sniezko- NAS Biotechnology for *virulence in pathogen (vcr1, vcr2) now limits utility in some areas Forest Healthy Dec 12, 2017 webinar 7

11 Resistance Types and Levels (Note: generally no 100% resistant orchard mixes) % MORTALITY (family means) in Resistance Trial* Major Gene Resistance (Single dominant gene) Partial Resistance (quantitative resistance) *greenhouse root dip test Healthy Dec 12, 2017 webinar

12 The fate of Major Gene Resistance in forestry???? FIELD TRIALS ARE ESSENTIAL Region 6 has largest array of field trials of any program in N.A. (for resistance to non-native pathogen-native forest trees). Long-term field trials are essential part of resistance program.

13 Conclusion #1 Tree Breeding is the key Is Biotech useful w/o tree breeding/tree improvement support? NO need integrating, not piecemeal solution More support for Tree Breeding is needed Very precarious status More Support for Tree Breeding (resistance) institutes needed or no need for biotech? One model: Dorena GRC 50 years celebration in 2016

14 Conclusion#2 Tree Breeder s Biotech tool wish list: Help define what is durable resistance Develop biomarkers for rapid resistance evaluation Speed up breeding ( insert genes.?) Use new of genes (chestnut example?), properly vetted Tools to help determine genetic control & mechanisms of resistance are similar phenotypes controlled by same genes/alleles? Develop biocontrols? Utility of endophytes,.. in combination with quantitative resistance And needs to be inexpensive, easy to use,.

15 What is the timeframe for breeding a tree to address pest/pathogen pressures? Depends on the species And level of resistance needed And when serious effort is made Depends on the background research Port-Orford-cedar example Original thought: NO RESISTANCE? Whitebark pine example Originally thought: MOST SUSCEPTIBLE SPECIES? Koa example Sugar pine & western white pine examples

16 How fast can a program proceed?* KOA WILT RESISTANCE Maunawili Trial Percentage Mortality OVERALL for 23 Families/Provenances % mortality a-c a-c cd a-d b-d a a-c a-d a-d a-c a-c a-d a-d a-c ab a-d a-d a-c a-d a-d TIMELINE: 1999: koa provenance trial at Maunawillli 2003: Sniezko, R Potential for selecting for genetic resistance to F. oxysporum (koa wilt) in koa for conservation, restoration and utilization in Hawaii. Trip Report (8/23/2003). Cottage Grove: OR. USDA Forest Service, Dorena Genetic Resource Center. 13 p 2007: First inoculation trial confirmation of Acacia koa family variation in resistance to FOXY, the putative causative agent of koa wilt in Hawaii (Dudley, Sniezko, James, Cannon, unpub) 10 0 d d Maunawili provenance trial Oahu Ko'olau Mts. provenance : Evaluate 100 s of families, setup seed orchards, setup seed zones, produce first seed. PROBLEM SOLVED? *Limitation: Continuity of Funding & staff Healthy Dec 12, 2017 webinar

17 What are the effects of traditional breeding on local genetic diversity and local adaptation in forests? LITTLE OR NONE (if done right and lucky)? Do those effects differ, and if so how, from the effects of genetic engineering on local genetic diversity and local adaptation in forests? POSSIBLY, but minimized if GE efforts fully engaged with tree breeders at a very early stage

18 WHITEBARK PINE (white pine blister rust resistance) OBJECTIVE White pine blister rust resistant whitebark pine seed that is 1) Resistant to WPBR 2) Locally adapted 3) Genetically diverse (seed from parent trees in forest or from orchards) **Make selections from each zone** NOTE: only Oregon & Washington portion of geographic range is shown programs vary somewhat by Region

19 PORT-ORFORD-CEDAR (Phytophthora root disease resistance) OBJECTIVE 1) Phytophthora lateralis resistant seed 2) adapted to planting areas 3) genetically diverse 13 Breeding Zones Selections within each breeding zone - over 14,000 selections Goal: Seed Orchards for each BZ

20 Do you see new or different risks presented by using genetic engineering in trees to address pest/pathogen pressures versus using traditional breeding? MAYBE Do properly no shortcut for commercial or publication expediency Aim for durable resistance Fully integrate with traditional breeding program hopefully from early stage Need to field test over long-term

21 Example: USFS s Dorena Genetic Resource Center Lead role in development of applied resistance USDA Forest Service & Cooperators >50 year history and continuity (50 th in 2016) Interface between Research and Restoration/Reforestation Works closely with Forest Health Protection & partners Examines all types of resistance simultaneously Facilitates the development of resistance in useable form

22 USDA Forest Service -- Dorena Genetic Resource Center Sugar pine WWP limber whitebark

23 Strategy Simultaneously evaluate both MGR and Partial Resistance Aim for long-term effectiveness More difficult and longer term seedling trials Unknown at onset what types exist And may vary geographically in the range of the species Field validation needed! Incorporate both types into orchard production population Breed to increase level and mix of resistances Maintain Genetic Variability Maintain Adaptability

24 How much resistance is there? Is it durable? % Infection over time WPBR example **ONLY A SUBSET OF TREES FROM ORCHARDS WILL BE RESISTANT** The proportion of western white pine (Pinus monticola) trees from 12 families with stem symptoms over time in one field trial in western Oregon. Family 4 is a susceptible control, Families 11 & 12 have major gene resistance, but a virulent race of white pine blister rust pathogen is known to be present in this area (graph from Figure 2, Sniezko et al 2012b). Note: not all infected trees will die. Healthy Dec 12, 2017 webinar

25 Port-Orford-cedar (Chamaecyparis lawsoniana) Phytophthora lateralis resistance: Original investigators determined there was no resistance, but turned out wrong Operational breeding program started in ~1996 (FHP proposal) Both MGR and quantitative resistance present (Sniezko) Port-Orford-cedar (a) tree in urban area, (b) large, healthy tree in southern Oregon, (c) dead trees in forest along a creek in southwest Oregon, (d) dead and dying trees along Highway 101 in southwest Oregon, (e) resistant parent tree (510015) surrounded by dead Port-Orford-cedar. (Photo credits: Richard Sniezko, a to d; Chuck Frank, e) [from Figure 1, Sniezko et al. 2012]

26 DURABILITY of P. lateralis Resistance FIELD RESULTS Family variation in %survival over time Extreme genetic variation in field resistance Durability of resistance (survival) to Phytophthora lateralis over time for 16 Port-Orford-cedar families at Foggy Eden trial in western Oregon (graph adapted from Figure 3, Sniezko et al 2012). Healthy Dec 12, 2017 webinar

27 Restoring Port-Orford-cedar using resistance to Phytophthora lateralis PROBLEM Photo: C. Frank SOLUTION SUCCESS 1)Select/breed for resistance 2) Maintain genetic diversity 3) Use adapted seed sources Healthy Dec 12, 2017 webinar

28 WHITEBARK PINE July 2011 status under **Endangered Species Act** U.S. Fish & Wildlife Service agreed that the whitebark pine, a wide-ranging tree species found on mountain tops in much of western North America, faces an "imminent" risk of extinction. The species was found warranted for protection but currently precluded due to limited budgets. Development of genetic resistance at Dorena Genetic Resource Center and elsewhere is a key step to successfully restoring the species in many areas. Healthy Dec 12, 2017 webinar

29 Partnerships in the Pacific Northwest help save an endangered species, whitebark pine (Pinus albicaulis): an example of dynamic genetic conservation Healthy Dec 12, 2017 webinar

30 What level of blister rust resistance is there? Healthy Dec 12, 2017 webinar %Cankering Whitebark pine families in SY2007R3 early data **Large differences among families!

31 Is there GEOGRAPHIC VARIATION in occurrence of Genetic Resistance? Surprisingly high levels of genetic resistance to the non-native rust exist (in some areas). o Example in map below, where parent trees have been inoculated with the disease and given a Grade of A-F, where A indicates higher level of resistance, and F indicates low resistance. Region 6 has the highest levels of resistance in whitebark pine recorded to date. Restoration plantings have begun on FS & NPS lands. Results shown are from SY2007 trial at USFS R6 Dorena Genetic Resource Center (Sniezko, unpublished) v1.0 Draft Contact Richard Sniezko, rsniezko@fs.fed.us, for more information.

32 WHITBARK PINE - Resistance to white pine blister rust Genetic variation among seed sources in percentage of seedlings with early blister rust stem symptoms ~15 months post-inoculation. The number of half-sib families represented in each seed source mean is indicated above the bar (varies from 1 to 42). The 18 Oregon and Washington sources refer to individual National Forest, National Park and Confederated Tribes of Warm Springs boundaries from which the seedlots were collected (Sniezko, unpub) Healthy Dec 12, 2017 webinar

33 GENETICS IN ACTION Whitebark pine restoration at Crater Lake National Park PROBLEM SUCCESS SOLUTION Develop resistant populations Maintain genetic diversity Maintain genetic adaptability Plant seedlings

34 Restoration planting at Crater Lake National Park (also a genetic resistance validation trial) **Opportunity for public outreach & conservation education**

35 NEEDED: Tools to fasttrack resistance development Healthy Dec 12, 2017 webinar

36 The logistics of applying that tool in the context of tree breeding? - need to incorporate genetic diversity & adaptability How does a tree breeder think about environmental risk? What is known about the harm from/risk of traditional breeding? What type of risk analysis is done for trees that result from traditional breeding? What is the federal and state regulatory oversight of traditionally bred trees? To your knowledge, when traditional tree breeding has been used to address a pest or pathogen threat, have there been unintended consequences? Using seeds directly from existing parent trees or their early generation selected progeny no new genes increasing frequency of rare genes - - Field trials help confirm no risk Progeny tests & Provenance trials may give some indications Healthy Dec 12, 2017 webinar

37 IMMEDIATE NEED: Forest Genetics Research and Seedling Production Capacity/Infrastructure To develop & deploy regionally adapted, genetically diverse planting stock with durable resistance Gap: Forest Service genetics and breeding capacity has been declining rapidly for the last 30 years, especially in the East, Midwest, and Rocky Mountain Regions. Less so in South & Pacific Northwest (Wheeler et al., The Evolution of Forest Genetics and Tree Improvement Research in the United States, J. For. 113)

38 Applied Resistance Programs Benefit Sometimes only feasible solution Solution oriented Public support Tool can be combined with silviculture, etc Green solution Organic Sustainable Little or no side-effects.but Sometimes long-term Sometimes uncertain outcome Not Inexpensive Healthy Dec 12, 2017 webinar

39 SUCCESSES* According to the IUCN Red List of Threatened Species, the species status of Port-Orford-cedar which was listed as vulnerable in 2000, has been downgraded to near threatened as of 2013, with anticipation that it will be listed as a species of least concern within 10 years, if current conservation actions, including planting resistant seedlings, are successful and maintained (Farjon 2013). Whitebark pine has been proposed for listing under the U.S. Endangered Species Act. The threats to the species are ongoing, and therefore imminent, and are now moderate in magnitude. The identification of genetic resistance to WPBR is one of the factors that has recently led to a downgrading of listing priority number (LPN) from 2 to 8 for whitebark pine in 2015 (USFS 2015 ). The status of the species is reviewed annually. Restoration with resistant seedlings will increase the level of WPBR resistant whitebark pine *programs are ongoing to increase resistance in all breeding zones, etc, but genetic resistance has been identified and is being used in first restoration and/or reforestation efforts Healthy Dec 12, 2017 webinar

40 Possible discussion topic (Role of Biotechnology) at The 6th International Workshop on the Genetics of Tree- Parasite Interactions: Tree Resistance to Insects and Diseases: Putting Promise into Practice Welcome! Make plans to attend the 6th International Workshop on the Genetics of Tree-Parasite Interactions on August 5-10, 2018 in Mt. Sterling, OH USA. For more information, contact Jennifer Koch or Richard Sniezko.

41 Acknowledgments Funding from U.S. Forest Service Region 6 Forest Health Protection and Genetic Resources Programs All Cooperators, partners & colleagues Co-workers at Dorena GRC Photos: Michael Murray, Molly Oppliger, Chuck Frank, Scott Kolpak, Richard Sniezko Jennifer Koch (USDA FS NRS) for many discussions over the years!

42 References Sniezko, R.A.; Koch, J Breeding trees resistant to insects and diseases: putting theory into application. Biol Invasions 19(11): doi: /s Sniezko, R.A. ; Smith, J.; Liu, J-J; Hamelin R.C Genetic Resistance to Fusiform Rust in Southern Pines and White Pine Blister Rust in White Pines A Contrasting Tale of Two Rust Pathosystems Current Status and Future Prospects. Forests 2014, 5, ; doi: /f Sniezko, RA Resistance breeding against nonnative pathogens in forest trees current successes in North America. Canadian Journal of Plant Pathology. 28: S270 S279