Wide Cross Wheat Landrace Project

[Mike Deyo]

Back around 1990 I became interested in developing a new landrace of winter wheat suitable for where I live in north central Ohio. I requested ~15 historical varieties of Ohio wheat from GRIN, and taught myself how to cross them. My goal was to have strong straw to resist lodging, normal height (not dwarf), strong tillering to allow less dense planting and good weed competition, and hopefully a hard rather than soft wheat. Later, I added to the diversity by crossing in wheats (also from GRIN) from similar climate regions, also macha, durum, turgidum, triticale, and spelt. I backcrossed to wheat to recover 6n, and to get back easier threshing, and good seed set.

After reading about the lack of diversity in the D chromosome, I learned how to cross durum with wild goat grass (Aegilops tauschii) and was successful with one cross. The early generations were not easy to work with, as they had a lot of wild tendencies. The head would break apart on maturity, and the husks around the seed were harder to remove than even spelt. Also low seed yield, many tillers with thin stems, but good vigor. I back crossed it with wheat to hopefully combine new genes from the goat grass into a more agronomic wheat population.

Over the years I have harvested plants individually, weighing the dry stems and measuring the height, computing the "density" of the stem (grams of stem weight divided by how long the stem was in inches). The thought is that plants with denser stems would also be stronger and resist lodging better. Because wheat is grown en masse, and conditions for lodging (high wind and rain when grains are green and full) are unpredictable, I wanted a measure I could do each year. I would discard seed from plants with weaker stems, and make crosses between plants with better stems. I have selected for no awns. I have also discarded the tallest growing plants, as 6 foot tall wheat is going to lodge in this climate, no matter how strong the stems are. 3 1/2 to 4 1/2 feet tall seems to be best.

Over the years, I can tell that the average stem strength of the population has improved. Biggest problems have been birds, and hand threshing a few hundred square feet of grain. I am experimenting with growing winter peas on the wheat. Developing suitable peas is a whole other project I have been working on.

[Tim DH]

Hi Mike,
   Thirty Five years of crossing Wheat! That must be a labour of love!!

   It had not previously occurred to me to cross my own wheat, I just pinned my faith on the natural pollination of the cultivars I started with.

   This pdf on the subject seems fairly comprehensive

https://www.wheat-training.com/wp-content/uploads/Wheat_growth/pdfs/How-to-cross-wheat-pdf.pdf

   The landrace I'm currently growing, derived from 'Wakelyns yq' doesn't strike me (morphologically) as particularly diverse. I suspect that my small area of growing is insufficient to maintain diversity, (And that is on the assumption that the previous growers hadn't 'bottle necked' it either!)

   Hopefully you have some local fellow growers who are committed to keep your landrace going?

Tim DH

[Mike Deyo]

Hi Tim,
 
I've enjoyed the process. I live close to an ag focused branch of Ohio State which has a good library of plant breeding journals.

My crossing technique is similar to the pdf you reference. I snip across the florets first with the scissors, just above the anthers of the main florets. So the anthers of the secondary florets usually get cut off, and I don't bother pulling out the secondary florets. If it appears secondary floret anthers were missed, I either remove the anthers with forceps, or I snip out the secondary floret with scissors.

I use the approach method for pollination. I prepare the female seed head, and put in a bamboo stake next to it. Have a large glass test tube, or small glass jar ready with water in it. I cut off a stem of the pollen parent that will be releasing pollen in the next few days, put it in the jar. If the stem is too long, I trim it shorter. Remove leaves that would be under water level, and the flag leaf. I've found that trimming a few florets like you do for the female parent can help with anthers extending out of the florets, with some genotypes. Tie a string to the top of the jar, and wrap the other end of the string around the top of the bamboo stake, finishing with a few half hitches that will be easy to untie later. Be sure the bottom of the male head is about an inch above the top of the female head. I slip a ~ 8" long piece of dialysis tubing over both heads to keep out pollen from other plants. It's 1" dialysis tubing, which is a clear film made from cellulose, so it lets air and moisture pass through. The male stem is just like a cut flower in water. It will live long enough to produce pollen successfully.

The advantage of the approach method is you don't have to try to find anthers that are just at the right stage to pollinate, the pollination takes place naturally over several day as the florets open on the male parent. You just have to check each morning, and raise or lower the jar, loosening and retying the string on the bamboo stake, to keep the male head about an inch above the female head. The male and female stems often grow at different rates, making this necessary. A string tied tightly to the stake, and loosely looped around the two stems just below the dialysis tubing helps keep everything in place when there are wind gusts.

Your land race is probably diverse in characters that aren't visible. If you are growing several hundred plants or more, and if there is a small amount of natural crossing going on, you are probably maintaining much of the original diversity that came with the seed you started with.

I don't have anyone else growing it. It's taken awhile to get it to a point where the undesirable characters are reduced enough. Because some of the original crosses were so wide, it took multiple generations of back crosses to improve seed set and to recover easier threshing and non-shattering heads. Next was reducing the prevalence of tall and weak straw. Other than that, I've tried to retain as much diversity as possible.

Mike

[A. Pel]

Thank you for describing your breeding technique - very interesting and educational.

[Steph S]

So nice to hear about this project! 
Non lodging wheat would be a great feature for my windy area as well.

I had to put my grain and peas projects on hold this year due to a bad vole year.  I think to grow wheat you might need a cat or two, at least in this area.  I had to harvest everything quite early as the beasts were taking it down before it was ripe. 

Also had some issues with fusarium head blight and other wheat diseases in 2023, and this gave me pause to think about management issues:  seed treatment to avoid carrying it forward,  working to remove host populations like barnyard grass, and of course the possibility of resistance breeding.
Some of the modern wheats are very resistant - I recall reading about Emerson, that's a winter wheat with full resistance to FHB, but I'm not sure if there are restrictions on using these new varieties for backyard breeding.

I haven't tried crossing wheat yet but I did watch a few videos.
Wheat genetics is even more challenging than the crossing process, eh.  So many sets.

Anyway it's great to hear from someone working with wheat. 
Would love to see some pics of your landrace.

[Mike Deyo]

My wheat population is not non-lodging, but it is getting better. I don't have a lot of photos, but I attached one from June 30, 2023. I had bird netting over them. You can see some of the stems the sparrows broke over when I took the netting off to harvest. I get some leaf rust, but it doesn't seem to reduce the yield a lot.

I had a lot of trouble with chipmunks and voles when I was living closer to woods.

[Steph S]

Lovely... they look quite tall.
I had a variable amount of leaf rust on the Blue Tinge Emmer landrace, and am trying to select for less rust, but TBH it did not seem to affect yield at all.   In fact the shortest of those (really short plants less than 2 ft tall)  were really susceptible to rust and shockingly put on heads in spite of having no leaves. 
Yeah, being in the woods is the issue here.  Voles, hares and squirrels, moose, birds - I've encroached on their habitat.  I don't begrudge a share but sometimes they take the big one.

[Mike Deyo]

They are similar in height to what was grown before the semi dwarf wheats came around as part of the green revolution. The old Ohio varieties (pre 1920) I got from USDA were mostly all 4 feet (1.3m) or more tall. Definitely prone to lodging. I'm guessing the straw might have been a more valuable by product earlier, when there were a lot of horses for farmwork and transportation. I find the straw to be valuable in the garden for mulching and increasing soil organic matter. I hope they are also more competitive with weeds in an organic farming context. Increasing the strength of the straw, to reduce lodging, also increases the yield of straw.

[Mike Deyo]

I found some film photos I had taken in 2000 and 2001 which show some of the crossing I was doing then. The first one shows the F-1 plant of a cross between a durum wheat and wild goat grass (Aegilops tauschii). Durum wheat has the genomes AABB, and it is thought that Ae.tauschii contributed the D genome to produce modern wheat with genome AABBDD. I used the durum wheat PI 405906, a landrace from North Macedonia as the female in the cross; and PI 603250 (TA 2377), a wild collected Ae.tauschii from Mazaandaran, Iran, as the pollen parent. Normally that cross would produce a triploid plant ABD, which doesn't produce seed without using sophisticated lab techniques. But I found a paper that had used PI 405906, which can sometimes produce fertile AABBDD seed when crossing it with Ae.tauschii. It did produce a few seeds for me.

The next photo shows it being backcrossed to wheat the next year. Also you can see the wild goat grass (Ae.tauschii). It is a pretty weedy plant. It's thought it contributed winter hardiness and tolerance of poorer soils to modern wheat, which has allowed wheat to be grown in more of the world than it's durum ancestor. The last photo shows how I was crossing wheat then, which is still the way I do it now.

It is thought that modern wheat originated from a relatively few spontaneous crosses in fields of cultivated durum wheat several thousand years ago, with wild goat grass growing as a weed in the field. The large wheat breeding labs have been doing crosses like this, on a much larger scale, to introduce new disease resistance genes and increase the diversity in the D genome of wheat.

[Steph S]

That is awesome, to get a few fertile seeds with the right accession.
I've actually read some work from Europe where they were concerned to deal with Aegilops as a weed, due to the occurrence of unintended crosses!
But doing the crosses that you want manually is a sane approach.  I can't imagine looking for a volunteer in your field, which you might easily have eaten by mistake.  If everything gets planted back, sure you may find some crosses, but this is only going to happen if you're growing a large acreage and conditions just right to produce crosses by chance. 
I planted some grains together, and found a few odd things in the grain that made me hopeful of a cross, but I didn't see any evidence of it in the growout.  Conditions for cross pollination might never be ideal in my climate, perhaps.

What color and shape is your grain?  the heads look dark.  I prefer a dark grain myself, for some reason they are more appealing cw the regular bread wheat.  Well, realistically, bread flour is inexpensive here cw the spelt and whole grain flours which are so much more nourishing and tasty.

[Mike Deyo]

Plus, the unintended crosses would not get harvested with the rest of the wheat, as their seed heads would shatter before harvest. Aegilops itself is a bad weed in wheat, in wheat growing regions. When I requested the Aegilops seed from USDA, you had to say what state you were in, and I think they wouldn't ship it to Washington state, for example.

The heads of my wheat vary from light color glumes, to darker. I would say the seed is red winter wheat, not white winter wheat. Here's a photo of a small sample, you can see some variation.

[William Schlegel]

Aegilops is a really interesting wheat relative. I've encountered I think two different species on rangelands in the Sierra foothills back in 2007 and here in Western MT over the years. I appreciate your wheat breeding efforts. Very cool. I backed off from wheat after some trouble with Hungarian partridge and perhaps ringneck pheasant eating too much of my tiny plantings. Trying some larger plantings this year to see if a larger patch size helps.

[Mike Deyo]

Here's some photos of my wheat I have planted this year. The first picture shows a space about 5 feet wide and 25 feet long. The half of the planted area closest to the camera are winter wheat planted with dwarf winter peas (of my own crossing). The farther end of the row are all F-1 plants from crosses I did last year. The second photo is a closeup the winter wheat growing with winter peas.

The Aegilops tauschii had weedy vigor and hardiness, lots of tillering, weak stems, and really difficult to thresh seeds, worse than spelt. The durums I crossed with had strong stems, and less vigor and hardiness. Over the years I've backcrossed with wheat to improve the ease of threshing, and then crossed promising plants, always selecting for stem strength to reduce lodging, as well as vigor. I don't plant seeds as close together as you do modern semi dwarf wheats. Mine tiller vigourously to fill up the space. I usually plant seeds about 5"X5", or 6"X6". The posts in the first picture are to hold bird netting later, sparrows and cardinals can be a big problem in these small patches.

[reed]

When did you plant your wheat?

[Mike Deyo]

I planted the wheat on 10-1-24 and 10-3-24. It was probably 5-7 days earlier than I should have done, with the warm weather we had in fall and early winter. But it worked out.