Northern Nut Research 2003 – John H. Gordon Jr.

 

Thank you for wanting my input on the nut research in 2003.  We need to look over the shoulders of researchers until our many problems are solved.    My research is slow moving year to year, making other research more interesting.

 

Dr. William Powell and Dr. Charles Maynard are engineering chestnut blight resistance in native chestnut.  Herb Darling started the New York Chapter of The American Chestnut Foundation in 1991 to work with the Forestry School located at Syracuse University to put a resistance gene into our hardy timber chestnuts.  One resistant gene into native chestnut for a resistant tree seemed simple at the time.  Not so.  The knowledge gained, and the gene packets made, seem worth the wait.  We hope that a selectable tree is at hand because the knowledge that is ever expanding and pointing toward the best resistant tree seems never to end.

 

Dr. Powell gathers genes, and makes gene packets with a group of resistance genes to permanently defeat blight.  Dr. Charles Maynard puts the gene packets into chestnut tissue, and propagates trees.  The “gene gun” and agro bacteria are used to transform embryo and callus cultures.  Dr. Fernando has recently begun transforming the DNA in pollen with the “gene gun” as a more direct route to transformed trees.  The transformed pollen is used on flowers to get transformed nuts.  I am leaving a lot of steps out which you could ask about as you wonder about them, for instance, that pollination is with sprouted pollen which is seen to fluoresce.  The resistance works even as a single gene packet on a single DNA strand, one chromosome, not needing any partner gene on the partner chromosome to express.  The seedlings from each flowering will have to be tested for resistance and the nonresistant culled. Gregor Mendel says half the offspring from mating of a transformed tree and a typical American will have resistance in half the seed population if controlled pollinating can keep out foreign pollen.  Some other genes in a gene packet are: 1). An illuminator gene to light up the transformed cells under florescent light so they can be seen and excised. 2). A Roundup resistance gene to allow this herbicide to eliminate any non-transformed cells, or trees.

 

Dr. Powell is working with a new gene, which is activated by blight spreading in the tree’s fluid tubes ahead of a canker.  Besides stopping blight in over-stressed trees, this looks like immunity.  Previously, the promoter genes in gene packets needed the formation of a canker to sense blight, and then turn on resistance genes.  The other packet genes, florescent, Roundup, in-tube resistance genes, are always on.

 

Dr. Powell is also seeking release from patents on resistance genes.  We hope to use genes from grain and other food plants.  Food genes are more acceptable to regulators, and the general public, than the frog and moth genes previously used.  Some resistance genes destroy the blight’s cell walls, some interfere with cellular transportation of nutrients and by-products, some change the pH of cankers to most advantage chestnut’s natural resistance as is evidenced in the high pH Chinese chestnut blight resisting cankers, and low pH blight friendly American chestnut cankers.

 

The work at Syracuse was NY State funded at $150,000 per year, but ended in two years when our state budget went into deficit.  Lately TACFNY has had to fund-drive to maintain students, and help buy a necessary new microscope to digitally record transforms.  It helps to see what you are doing.  Before 2003, 30 specks of transform in a mass of tissue were the best the students could achieve.  Now, 70,000 transformed specks are being achieved.  Because probability says 69,999 specks will wink out in about a year to reveal the single stable DNA transform, we finally got up to speed.  Nobody let us in on this information until the 70m spots were achieved.

 

The American Chestnut Foundation has started tens of acres of hybrid chestnut near Meadowview, Virginia.  Dr. Fred Hebard and coworkers are at their third backcross generation with American which is the 15/16 American thought necessary for distribution.  15/16 allows resistance gene cooperation between two Chinese chestnut chromosomes holding them.  31/32 American chestnut is as near native as backcrossing gets because chestnuts have 32 chromosomes, but lacks pairing, and may therefore never yield resistance.  The Pennsylvania chapter of TACF has field trials of these hybrids.  Pennsylvania trees will be culled after given blight in Dr. Hebard’s blight resistance test.  This will bring the chestnut breeding north.  Breeding and testing has to move north because we have found only the high ridge trees from the Smokies are tip hardy in our climate. 

 

The almost immune, 100% NY native chestnut will be brought to the market in the foreseeable future, but not soon.  The resistant, 15/16 hybrid chestnut may be released in a few years.  This delay reveals why breeding is the first choice for today’s nut improvement.  That said, the already-in-use packets at Syracuse in trees of chestnut, poplar, elm, and spruce are also to be tried in butternut and beech.  It is time to somehow preserve blight affected nut trees, which have great qualities, but little resistance.  They should be saved out of the reach of blight.

 

I told Tom Molnar who is surveying for good filberts that I made a big mistake in not saving a filbert that had the every node production (often several flowers at each node and along peduncles of catkins for a long bloom season like Ennis), plus the melting kernel of almond or tree hazel. This filbert bore itself all the way out of existence, which seems true of all overly productive filberts grown against blight pressure.  I would guess the ability to pollinate is directly linked with Eastern Filbert Blight susceptibility.  EFB is even taking down most of my young filberts just as they start to bloom.  Because very few productive filberts seem immune to EFB, I have a small hope of recovering this filbert among its seedlings.  Without EFB resistance it must be recovered away from the blight.  I have a bit of hope because some nuts from this filbert must have crossed with the resistance of Faroka, which was grafted only a few feet away, and had many seed started.  If resistance is found, it is likely to be only one gene, which could easily be defeated by EFB.

 

Right now I have a semi resistant filbert with a super-appealing flavor that needs the sense-without-a-canker, in-tube resistance gene.  Unlike chestnut blight EFB invades the wood of filbert, going far beyond where cankers burst from filbert bark.  The Gassaway European variety, and tree hazels may have the mechanical suppression of blight by having tiny fluid tubes where blight gets stopped.

 

The chestnut gall wasp has been working its way up the Appalachians from Tennessee and Georgia.  It has gotten a boost into Ohio from nurseries, which have distributed infected trees.  We see England’s Orchard and Nursery from Kentucky distributing gall wasp resistant trees. Is anyone testing these in a climate like Simcoe’s?  Gall wasp resistance is a mechanical tightness and smallness of bud coevolved at the source of the wasp, Japan.  It has been difficult to get Japanese chestnut to prosper here due to our short growing season and harsh winters where Southwest Injury destroys the freeze prone bark receiving sun-off-snow during a period of sunny days and frigid nights.  Southwest injury is the likely reason oriental chestnuts were not recommended north of Maryland.  The good news is that Japanese hybrids have been around for years due to Japanese’s ability to produce very large nuts in a cool climate like ours.  Many of the hybrids already have small, tight buds, but Southwest Injury remains a problem that we are slowly breeding out.

 

Now that Eastern Filbert Blight has invaded the commercial hazel orchards of Oregon (filbert is called hazel on the West Coast to distinguish it from the Eurasian crop). Dr. Shawn Mehlenbacher of Oregon State University has been bringing out hazels bred for EFB resistance.  The first numbered selections were bred from the resistance of Gassaway, a European variety.  Doug Campbell obtained some of the first numbered OSU selections, which we have found to be EFB resistant.  The bad news is they are very similar to Gassaway, being small nuts, small bushes with small drab leaves, and small crops.  However, these selections from more than ten years ago were not released.  West Coast nurseries are propagating the recent releases.

 

Professor George Slate of the Geneva, NY Agricultural Experiment Station of Cornell University is known for his breeding of strawberries, raspberries, and blue berries.  His mentor was George Darrow who started him on small fruits before moving on to the USDA Experiment Station in Beltsville, Maryland.  Professor Slate stressed that breeding parents should be reused when they had offspring that were superior.  He collected Bixby, Jones, and Rush hybrids, and bred with European selections, many gathered by a nurseryman in Rochester, NY.  We discovered that Slate filberts numbers NY 104, 110, 200, and 398 were EFB resistant; this about ten years after Geneva rouged Slate’s plantings of filbert (as well as persimmon and pawpaw).  The hybrid filbert we find that has resistance and wide distribution is Potomac (another small nut).  However, the resistant Slate filberts are all longer, larger and later ripening nuts due to back crossing with European, probably Luisen (or Loriesen because the tag at Geneva was mangled) that had some resistance at Geneva. 

 

 Tom Molnar is a graduate student at Rutgers in New Jersey who was enlisted by Reed Funk to find and grow nut selections for NJ climates.  Molnar is surveying for all temperate nuts.  He noticed resistance in purple filberts, as have we.  Molnar is trying to breed these to obtain a resistant ornamental yard bush.  He has brought back filberts and Persian walnuts from as far as Uzbekistan and Turkistan.

 

Persian walnuts do so poorly for me that even NJ seems too tough for Persians.  NJ may have the long hot season that allows them to grow their natural six feet a year.  Buffalo has that growing season once every ten years, or so.  What we also have is walnut blight to the extreme.  Either of these produces too shabby and shrubby a Persian walnut tree to crop, or even look like a nut tree.  Suffering many dead tips and buds from deep cold, frost, or blight, new growth is sent from adventitious and blind buds, thus making a tree look like a bush.  The harvest is death, not nuts.  Often Persians in town in full sun by a brick home will look like a nut tree, but seldom on the farm where weather is harsh and blighted trees are near.  For a while research was making progress with Dr. Loy Shreve at a university near Uvalde, Texas.  He made trips to the old Soviet Union, bringing back Persians from Romania, and nearby states.  However, his work and record seems as lost as Slate’s except we still have his Sylvania and S3 cultivars.  Uvalde is so far from here that we never visited.  I would welcome any recent information on Shreve plantings.  Uvalde is in the hill country of Texas, and a place with fluctuating heat, cold, and many spring frosts.  It might be the ideal place to take the frost resisting steps needed to breed North American Persians.  I have a sinking feeling that commercial Persians were very discouraging at Uvalde due to frost. 

 

The New York Nut Growers Association is contemplating a Persian walnut project due the high value of the nut, and the state's vast lake-moderated acreage.  Anyone trying Persian breeding should start with Shreve selections and Lake.  Identify blight susceptibility by its summer burn of growing tips, brown spots on grafting wood, and cankerous vertical splits of two year and older bark; all in small seedlings.  Get rid of these as seedlings. Do not wait for cropping when most or all of the nuts turn black.

 

The ambition of Rutgers breeding program is to fruit nut generations as fast as Slate’s small fruit generations by expert growing; nuts as fast as raspberries.  Oregon selections are being tried as well as Slate EFB resistant filberts.  I have been cooperating with Rutgers in this project with nuts from EFB resistant filbert, as well as Emma K type black walnut, Iowa pecan, hican, hickory, heartnut, and chestnut. 

 

The 2003 season brought forth a 20-nut crop on a 10-year-old hican graft from Ralph Kreider of Illinois.  The nut is white, 1” by 2”, thin shell, pecan looking kernel with a shellbark flavor, off a small shagbark type tree, 3 inches diameter by 12 feet tall.  I am hoping that Molnar succeeds using his small fruit magic on these.  If he achieves one or two seedlings it will mean to me that the bird predation has not been solved.

 

One reason I am saying the above is to point up the difference between hickory hybrids and heartnut-butternut crosses.  The Kreider hican crop was really 22 nuts; one to a bird pecking, one to me to evaluate (yum, yum), and 20 sound nuts that typically germinate.  By comparison, a 22-nut crop off a heartnut-butternut hybrid is typically 12 aborted, 5 with internal breakdown, and 5 that germinate.  Is it blight, or lack of calcium?  Is the heartnut-butternut cross that wide that the chromosomes are often incompatible (or an RNA problem)?  Is the pecan-hickory that close a cross that chromosomes almost completely match?  Because hickories and pecans have grown with each other over eons, and blend into each other with many crosses I predict nut stability is a close cross phenomenon.   What makes this event rare are weevils and squirrels eating most hicans, so that there are relatively few hicans to choose among?  Certainly we can breed and evaluate many hicans producing many, large kernels in a short season.

 

Another pecan conclusion in this cool short 2003 growing season is that small Iowa pecans, less than an inch, and larger Iowa pecans, longer than an inch and a quarter, will ripen in the same season.  This makes smaller nuts quite disinteresting.

 

I could never see why black walnut has remained a nut of marginal interest.  That may be changing.  New Jersey is trying to reduce shell thickness a bit below the unique thinness of Emma K so that lobster-claw crackers can be used.  This would let blacks crack like Brazil nuts.  There has always been a cottage industry cracking out kernels from black walnuts, and even an industry in Missouri where Hammond’s Products Co. produces kernels and abrasives from walnuts.  Norm Hanson in Iowa, Francis Woodward in New York, and Ernest Grimo in Ontario have been producing cured in-shell walnuts and clean kernels from their own grafted trees.  Whole nuts cost about 0.50usd per pound while cleaned kernels are about $6 per pound.  10 pounds of cured, varietal nuts produce 2 pounds of kernel, so cracking and cleaning your own saves $5.75 per pound of kernels.  However, Ernie says $6 is cheap for his hour picking kernels.  Each grower is trying to mechanize the shelling, and cleaning process.  You can ask Ernie about progress, but not about how much buying and setting up cleaning equipment has currently added to the cost of cleaning.

 

All nut growers are nut researchers, but it is a great help if they are real nut growers as defined by actually producing nuts or seedlings.  Good nuts spread like gossip while nut projects often die out.  Nut interest is in worthwhile nuts rather than the intricacies of research.  Plus, nuts are the fruit, the hard copy of the nut research many people and institutions are doing, and what growers are awaiting.  We need nut production to shell the kernels of information from the fragments of research.