Chestnut Blight Case Study 1: American chestnut - Specialty Crop Regulatory Assistance
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
Case Study 1: American chestnut
American Chestnut Research & Restoration project
SUNY College of Environmental Science & Forestry
Chestnut Blight
(not-for-profit, restoration program with TACF since 1990)
Current research team: Andy Newhouse (PhD grad student)
Bill Powell (Director) Tyler Desmarais (MS grad student)
Chuck Maynard (Co-Director Emeritus) Dakota Matthews (MS grad student)
Linda McGuigan (TC lab Manager) Vern Coffey (MS grad student)
Allison Oakes (Post doctoral fellow) Yoks Bathula (MS grad student)
Kaitlin Breda (Admin assistant) Xueqing Xiong (MS grad student)
Vanessa Gravenstone (Greenhouse Man.) Erik Carlson (MS grad student)
Andrew Teller (Research Analyst) Hannah Pilkey (MS grad student)
Masoumeh Khodaverdi (grad student)
Many undergrads, high school
students, collaborators, and
many volunteers…
The work of well over 100 people over 28 years
1
Public engagement (from beginning)
• in 1989, founders of TACFNY, Herb Darling and Stan & Arlene
Wirsig, asked us to try GE
– Annual meetings, tours, and reports
• ~20 public presentations per year with Q&A
– Given by team members and myself
– Flower shows and Garden clubs, landowner groups, libraries, fairs, schools K-
12, NASA, etc.
• Many articles - The Conversation >88K reads
– PBS TV and radio, CBC TV and radio, WIOX community radio, The Atlantic,
The Wall Street Journal, National Geographic, Scientific American, The
Economist, Smithsonian, etc.
Public engagement
• Interacted on multiple occasions with Haudenosaunee leaders
in New York State
• Reddit ask me anything (AMA) with 1,240 participants, 89%
up-voted
– unsolicited Reddit open discussion involved 35,415 participants, with
90% up-voted
• engaged non-regulatory governmental agencies
– New York State Department of Conservation (DEC)
– U.S. Forest Service
– Fish and Wildlife Service
– National Parks Service
Public engagement • Webpage: www.esf.edu/chestnut • Two Facebook pages (~2,800 followers ) – facebook.com/americanchestnutgroup/ – facebook.com/groups/esfchestnut/ • Also interact with chestnut growers on TACF- GROWERS@LISTS.PSU.EDU • Workshops • Answer many email questions • And more…
Wood products
Agricultural Social/historical
Chestnuts roasting on an
open fire,
The Christmas Song
(by Torme and Wells in 1946)
1915 William Bray (first Dean of college)
and American chestnut
“It is claimed that in certain
districts the farmers
realized more income from
the sale of chestnuts than
all other farm products.”
Not orchards, but wild trees
Bray, W. L. (1915). The development of the vegetation of New York State (Vol. 16, No. 2). The University.
Keystone forest species (environmental benefits)
Ecosystem restoration goals different
than agricultural goals
European chestnut
American chestnut
(Chinese similar)
Other differences:
Restoration – tall canopy trees
Agriculture – short orchard trees
Restoration – diversity
Agriculture - consistency
Forest History Society
Invasive fungal specie: Cryphonectria parasitca
Chestnut blight in the U.S.
~50 years spread through natural range
killing ~4 billion American chestnut trees Chestnut blight on related species:
Allegheny Chinkapin, C. pumila var. pumila
Ozark Chinquapin, C. pumila var. ozarkensis
1876 Japanese chestnut
started to be imported
In 1904, discovery
of chestnut
blight in the Bronx
Zoo (Merkel)
Chestnut blight also survives on oaksAfter over a century of unsuccessful
attempts at combating the blight,
what are the choices for
restoration?
Chestnut hybrids are OK for ornamentals or crops,
Not for restoration
Japanese chestnut
C. crenata
American chestnut Chinese chestnut
C. dentata C. mollissima
European chestnut
C. sativaAre hybrids suitable for restoration?
Unlikely to replace the
American chestnut
Lion: Panthera leo Tiger: Panthera tigris
American chestnut
Castanea dentata
Chinese chestnut
Castanea mollissima Liger: Panthera hybrid
Better ways:~38,000 CC genes + ~38,000 AC genes
Unwanted traits
TACF Meadowview
Farm, VA
Dr. Fred Hebard
(started 1983) Unwanted traits
Dr. Jared Westbrook
(current)
Unwanted traits
Goal is for 1/16 What if you
Chinese chestnut didn’t have to
genome to contain select out any
the required 3 to 6 unwanted
more blight traits?
resistance loci
(#genes?)Breeding & Transgenics:
(Both viable options & both have advantages & disadvantages)
Chestnut has ~ 38,000 gene pairs
1/16 Chinese chestnut genes:
vs
CC AC
10 pages or 2,375 words It was very exciting at
that seasonblight
to roam the
resistant
then boundless chestnut
Making very small woods of Lincoln, …
changes, adding Henry David Thoreau, “Walden: or
Life in the Woods,” 1899
only 2 words
100% American chestnut + blight resistanceOxalate oxidase (OxO) from wheat
ubiquitous enzyme in many plants & fungi
(non-gluten enzyme)
Wheat
Rice Goatgrass
Barley Stiff brome
Sorghum Wild einkorn
Banana Perennial
ryegrass
Oil palm
Castor bean
Date palm
Insulin plant
Barrel clover
Spiny amaranth
Strawberry
Beet Azalea
Cacao Mosses (6 spp.)
Fungi
Peanut
Peach & ApricotOxalate oxidase (OxO) from wheat
ubiquitous enzyme in many plants & fungi
(non-gluten enzyme)
Detoxifies oxalate (oxalic acid)
Not a pesticide (more like an antitoxin)
Does not kill the fungus, no ‘cidal’ activity.
Since the fungus survives, less selective
pressure to overcome the oxalate oxidase.
On transgenic American chestnut, changes
the fungal lifestyle from a pathogen
to a saprophyte (coexist).
(like on Chinese chestnut & some oaks)Oxalate oxidase assay
Very important to have
negative controls
without oxalate
Run time:
2 hours for wheat germ
4-12 hours for chestnut
(NRC GE Tree webinar)Examples of OxO leaf disk assays
(- OA left, + OA right)
Ellis 1 (NT) Darling 38 (T) Darling 28 (T)
Darling 11 (T) Darling 311 (T) Darling 18 (T)
Zhang et al. 2013OxO protects plant from oxalic acid (OA)
OA leaf disk assay (no fungus)
Green – living tissues
Brown – dead tissues
Wild type (Ellis 1)
American chestnut
‘Qing’
Chinese chestnut
Chinese chestnut has no
Oxalate oxidase or
Oxalate decarboxylase
So, ?
oxalate-CoA ligase
Oxalyl-CoA Decarboxylase
Formyl-CoA Hydrolase
Formate dehydrogenase
(Dakota Matthew’s assays)Isolation of C. parasitica from small stem assay
cankers
Example of Darling 54 cankers Isolation of C. parasitica 52 DPI
Darling 54 Darling 54
Qing
Tree & fungus co-exist.Inheritance of blight tolerance Pollination with transgenic pollen
Inheritance of blight tolerance
“mother tree”Inheritance of blight tolerance Pollination with transgenic pollen
Inheritance of blight tolerance Pollination with transgenic pollen
Inheritance of blight tolerance
Bags opened in labSmall stem inoculations 21 DPI
D58 T1s from tissue culture
Ellis 1
Canker height
Qing
D58 T1-01
D58 T1-20D58T1s Girdling status 21 DPI
(0.3– 0.5 mm diameter stems – EP155)
Outdoor shade tent,
Note: no-takes were not analyzed not temp controlled
(~30% of total, ~40% T and ~10% NT) greenhouse2.5-year-old Darling T1 seedlings
three D58, one D54, OxO minus siblings
18 DPI (still early), EP155
Initial inoculation
Approximate
area
WxH
2Tests for regulators
SamplesDarling 58 insertion site in
chestnut genome
Darling 54 found to be inserted in an intron of a predicted gene
Set aside pending further testing. Focusing on Darling 58.Transgene did not affect
respiration or photosynthesis of T1
chestnuts in an orchard setting
Light Full light
response response
curves of curves
attached
leaves
P-value of Data at low
Variable transgene light: leaf
(P-value < 0.05 significant difference) effect respiration in
Respiration in the dark 0.2 dark and
light via Kok
Respiration in the light 0.6 method
Light-saturated photosynthetic rate 0.3
Quantum yield 0.7 Rlight
Light compensation point 0.3 Rdark
Light saturation point 0.9
Dr. John Drake and Cindy DuongMany typical comparative studies,
plus additional experiments
for restoration trees
(slide by Andy Newhouse)Tadpole Survival:
Cox Proportional Hazard Model
SM – Sugar Maple
AB – American beech
D4 – Transgenic
NT – WT American chestnut
HY – Hybrid chestnut
CC – Chinese chestnut Increasing Survival HazardTadpole Development
American
chestnut
Goldspiel, HB, Newhouse, AE, Gibbs, JP, and Powell, WA. 2018. Effects of Transgenic
American Chestnut Leaf Litter on Growth and Survival of Wood Frog Larvae.
Restoration Ecology (in Press)Bumblebee Interactions
with Chestnut Pollen + OxO
Photo:
William PowellBee/pollen with OxO feeding study Cox hazard ratio for bee survival. Higher hazard ratios indicate more hazardous conditions in terms of increased mortality. “Pollen” indicates OxO concentration; “Source” (A, B, C) indicates source colony (hive). Newhouse, AE, Allwine, AE, Oakes, AD, and Powell, WA. 2018. Effects of Oxalate Oxidase enzyme on bumblebees feeding on pollen. Manuscript in preparation for submission to Ecotoxicology and Environmental Safety
Chestnut is not a weed
• As American chestnuts moved west, not considered a weed
• Natural chestnut reproduction rates (Rogstad and Pelikan 2014). :
– zero offspring per year from trees aged 0-7 years
– 0.05 offspring/year from 8-year-old trees
– 0.13 offspring/year from 10-year-old trees
– 0.2 offspring/year from 12-year-old trees
– 0.5 offspring/year from 17-year-old trees,
– 4.9 offspring/year from trees aged 70 to 113 years
• Natural spread of American chestnut would likely be very slow, possibly at
the rate of a few kilometers per century; though after many decades this
could accelerate as the volume of annual seed source increases (Paillet
and Rutter 1989).
Rogstad, Steven H., and Stephan Pelikan. 2014. “Restoring the American Chestnut: Optimizing
Founder Spacing to Promote Population Growth and Genetic Diversity Retention.” Restoration
Ecology 22 (5): 668–75
Paillet, Frederick L., and Philip A. Rutter. 1989. “Replacement of Native Oak and Hickory Tree Species
by the Introduced American Chestnut (Castanea Dentata) in Southwestern Wisconsin.” Canadian
Journal of Botany 67 (12): 3457–69What about crossing with organically
grown chestnut hybrids?
1. Growers already have a
system to deal with this in the
case of Internal kernel
breakdown (IKB)
2. Internal kernel breakdown is
caused when Chinese cultivars
pollenate European hybrids like
Colossal.
3. Recommendation, separate by
at least 1000ft.
Same recommendations can be used.A unique opportunity with the Darling
lines of blight resistant
American chestnut:
Rescuing the surviving
genetic diversity.
18 in. DBH American chestnut
Manlius, NYUnique feature of the ‘Darling’ American chestnut trees:
Rescuing genotypes surviving trees
Supplier of pollen
Genotypes
Regionally
adapted
½ mother & ½ father
Parental
allelic
pollen seed composition
Continue to
maximize
out-crossing
Allows:
Transgenic
Allelic rescue,
American
local adaptation,
chestnut
and increases
genetic diversity
TACFNY LSC “Mother” Trees Offspring
Or surviving wild population 50% OxO & fully blight resistance
Or backcross trees 43Outcrossing Darling 58 American chestnut Lead Event
Progress to Date on USDA Permitted Sites
McCabe R39TA, NY mother tree Darling 58 (D58), Ellis 1 background Fert9T2, NY mother tree
Outcross 1 (OC1) D58+ #16001 T1 D58+ #16020 T1
pollen
American Chestnut mother trees in 2018 (12 new AC lines):
WB275-27 (southern source)
Johnnybrook 40A
Lasdon
Fert2T2 12 new mother tree Pending
H1-12H66 backgrounds from 2 Regulatory
Fert3T1 father trees. approval,
Outcross 2 (OC2) Brag 8G Lasdon
this is what
In progress Crumhorn
Fert9T3
Pollen from the may be
I64-J2 resulting OxO+ distributed for
Pond seedlings can make breeding
(808+ nuts) AC Seedling McCabe Plot OC3 generation. from SUNY-
Fert9T2* (repeat from last year) ESF
Others for experimental use:
B3F3 (Fred’s selected)
F1 Hybrid (Chinese/American)
Allegheny Chinquapin
EC Marron du Var (European chestnut)"We humans are more than consumers,
we have gifts of our own to give to the
earth."
Dr. Kimmerer at the U.N.
Questions?You can also read
