Friday, 2 October 2015
An Organic Potato Seed Production and Potato Breeding Day at Duane Falk`s Farm
On Tuesday, Mr Ferdzy and I went to an afternoon workshop on potato breeding and potato seed production sponsored by the Ecological Farmers of Ontario and The Bauta Family Initiative on Canadian Seed Security. It was held at the farm of Duane Falk, near Hillsburgh. About 10 enthusiastic and waterproof people attended.
As a "backyard breeder" I was interested to see that this major project in developing new varieties of potatoes suitable for medium to large scale (mechanized) organic growing actually requires a relatively small amount of space. The garden above is where Duane grows the parents of his seed lines, and the potatoes being grown out from their seeds. Parents are in one row (originally two rows but one came up when his grain projects in the next section were harvested) on the right hand side.
Duane Falk (centre, holding the white umbrella) is a very interesting fellow. Originally from a farm in Montana, he acquired a PhD at the University of Guelph on the subject of wheat breeding. He began his career in New Zealand, where he spent 4 years working with barley breeding. Ultimately his career brought him back to Guelph, where he continued working with barley and wheat. In 1999 he bought this farm, and 4 years ago he retired to it. The farm consists of 85 acres, some of it in bush, much of it now in hay. He knew when he bought the farm that it would be good for potatoes, as he found an old horse-drawn potato harvester in a fencerow. When he pulled it out, he found it was still working, and he used it for several years. Currently, he has 4 small field plots he uses for his work with potatoes, with a fifth being developed this year.
Through his work at Guelph, Duane came to know Gary Johnston, the man who developed the Yukon Gold potato, amongst a number of others, including the excellent but never fully commercialized Ruby Gold. Today Yukon Gold is the second most popular potato in the world, only after the Russet Burbank. Gary Johnston continued to breed potatoes in his backyard after he retired from Agriculture Canada, and eventually Duane inherited his personal breeding collection. For a few years, Duane continued to work with this material on a hobby basis.
In 2014, the Bauta Family Initiative on Canadian Seed Security asked him if he knew anyone who could start a potato breeding program. The person he knew... was himself (I should think so!) They pay him a much more modest salary than the University of Guelph, and make sure he can attend all the potato breeding events that he needs. Anything released by this project will belong to the organic growers who will be doing the actual selection and evaluation, and likely be in the public domain, unlike most potato breeding efforts.
Mind you, Duane compared potato breeding to buying lottery tickets. At what point, he mused, do probabilities become so small that they are effectively zero? Both lottery ticket purchases and potato breeding efforts fall into that category, he concluded. I conclude that he doesn't buy lottery tickets but he does breed potatoes... well human beings just aren't completely rational, it's true.
Here he is holding a few lottery tickets, I mean potato seed balls, which contain true seed. As I've noted before, they look like miniature unripe tomatoes or maybe eggplants, to both of which potatoes are related. Duane commented that a good clump of large seed balls are probably self-fertilized, while when a plant produces few and small seed balls, the odds that it has been out crossed go up. Both are likely to be useful, as even self-fertilized potatoes may contain quite a lot of diversity. Duane doesn't usually attempt to make manual crosses, although in some special circumstances this may be necessary. He lets the bees do it and takes pot luck. The first trait Duane is looking for is fertility. You can`t breed plants if your parent material is infertile, and that is currently the case with a lot of potato varieties.
Duane prepares his potato seed by whizzing a few preferably rather soft and squishy seed balls in a bullet blender with some water and a pinch of dirt, the bacteria from which help break down the gelatinous seed coatings which may inhibit germination. The mixture is left to ferment for a week or so, then rinsed clean and dried on paper coffee filters, then stored in paper envelopes. He soaks them for an hour before planting them.
A note for anyone wanting to try this at home - now is the time to collect your seed balls and get planting. Duane says that the mini tubers resulting from the first planting need 4 to 6 months cold treatment before being planted out again, so if you want them to be going out next June you will need to get going as soon as possible so they can spend late winter and spring in the fridge.
The prepared seed looks much like tomato seeds, but is smaller. Duane's is also much browner than mine has ever turned out; I think because he treats his rougher with a pinch of dirt in the processing and a longish ferment.
Seeds are grown out in flats of 32 cells, in a mixture of sterile seed starter and turface. A major local potato grower is going to allow him to store these flats overwinter in his facility for cold treatment, which will reduce the work of managing them quite a bit.
Here, Duane is talking about some of the things that make a good potato. This one is already showing some problems. The tubers are attached to the plant by rather long stolons, which will make hilling and harvesting the potatoes difficult. Conversely, if the stolons are too short, the resulting potatoes will be jammed together at the base of the stem, and are likely to be misshapen.
The list of requirements in a new potato is very long: plant growth habit both above and below ground specifically to be amenable to mechanized farming, resistance to pests and diseases, high tuber production, size and shape of tubers including eye conformation (they need to be neither deep nor with protruberant "eyebrows"), tuber quality (different uses do have different requirements) and storage qualities. Flavour? Yes, that's on the list somewhere.
It is also important that the potatoes be edible. Duane told us a hair-raising story of a variety developed in the U.S. in the 1960s, Lenape. It was a fine chipper with excellent pest resistance. Gary Johnston grew some at the University of Guelph, and one day he took a few home and ate them for dinner (and nothing else - his wife was away and he was batching it). He got very sick, although he made it in to work the next day where he complained about how ill he had been the night before. The thing about working at a university is that you get to complain to some very educated people. One of his listeners was a toxicologist, who asked some pertinent questions and determined that the potatoes were the problem. They were sent for testing, and found to be very high in glycoalkaloids. Potato plants generally are high in them, but usually they are confined to the leaves and stems and other green portions of the plant. (This is why you should not eat potatoes that have been exposed to the light and turned green.) Through this unlikely but ultimately fortunate set of circumstances, Lenape was withdrawn from circulation - after certainly having killed some of it's unlucky consumers - and now all potatoes must be tested for glycoalkaloids before being registered as new varieties.
New varieties are generally developed by growing out seeds, but there are other possibilities. Here Duane holds three potatoes; the first being Ruby Gold. At one point he found a Ruby Gold with a section that had mutated, and had a light pink skin with red eyes. He saved that section and planted it out. It too threw out another sport, mildly different again. Oddly, this last one is up to 20% more productive than the original Ruby Gold. While these potatoes are distinctly different from Ruby Gold, they cannot be registered (by Duane) as new varieties, as they are too closely derived from Ruby Gold, the intellectual property rights to which are held by the University of Guelph. There is, however, no reason he cannot collect seeds from these plants and use them in his breeding work.
On the table you see the progression of growing potatoes from seed. From right to left, you see the (usually) single mini-tuber produced by growing out a true potato seed. When that tuber is planted, it produces a certain amount of tubers, which are stored in red net bags to keep them together. Four of these are planted out the next year, and the results stored in a yellow net bag. Next, 20 of those tubers are planted out, and the year after that a full row 30 metres in length. Selection against defects is practiced at each step and only the best are saved for further evaluation. Assuming that a potato has not been discarded for one reason or another during this process - with each step taking a year - the results will be distributed for multi-location trials. Only a small percentage of the potatoes will make it that far.
Next, we went out into the field and Duane dug up some plants - this one looks rather nice: numerous tubers and clean, even though blight killed the leaves. Many of them have been visited by potato late blight, resistance to which is one of the most important things any breeding program will be looking for. It's not as easy to identify as you might think; just because a potato plant does not die when exposed to it does not mean it has the kind of resistance breeders want. All potatoes are moderately resistant to it until they reach the stage where the plant is flowering and tubers are forming. A plant that is still green now is more likely to be late in breaking dormancy and/or forming tubers than to be resistant to blight.
While complete resistance to blight would be ideal, even partial resistance can be helpful. Blight may just kill the leaves, leaving the stems still relatively healthy. This is useful resistance, as the potatoes may still finish ripening and the potatoes may stay sound. Less resistant plants will have the stems die too, and completely unresistant plants will have the potatoes rot in storage as the tubers are also affected by the fungus. This was the case for most of the potatoes grown in Ireland at the time of the famines of the 1840s.
Duane says the above plant is the kind of plant that many organic farmers tell him they want, because it is low and spreading and will suppress weeds. The problem though, is that it is very unsuited to mechanical hilling and harvesting, because that spreading foliage will be hacked to bits. Duane is looking for short, upright but densely foliated plants.
These rows of seedling potatoes were planted out quite closely, with the tubers about 8 to 10 inches apart. Many have already died down, others are just coming up now. Those ones are essentially selecting themselves out of the project, needless to say.
These are some plants from crosses with a northern Chilean variety. In theory, they offer some valuable genetic material, but in practise, potatoes are very day-length sensitive plants. These ones have only just started to flower and form tubers in response to the recent equinox. That's far too late here in Canada, and few flowers and no seeds were produced. Also, they are throwing out numerous very long stolons and just starting to form tubers; as noted, not a trait commercial potato breeders are looking for. Unless Duane can induce these to produce seed, and that seed shows some amenity to adapting to long northern summer days, this will be a genetic dead end for him. He suspects that although potatoes originated in northern Chile and Peru, most European (and now North American) varieties came out of southern Chile and Argentina, where they had already adapted to long day growing seasons.
Duane examines another potato. He has quite a number of Latvian varieties, and in fact he handed out some seed balls from one of them, called Imanta. (Yessss! Score!) Other varieties specifically mentioned include Agria, Island Sunshine, Chieftan, Dark Red Chieftan (apparently no resemblance to Chieftan) Atlantic, a Texas bred russet variety, Kennebec, and a traditional purple skinned variety from the Madeleine Islands, which I coveted something awful. Duane has had access through his professional contacts with a wide range of potato growers both professional and amateur, and has collected some amazing material. He mentioned a wild potato with hairy leaves and stems, which have resistance to leaf hoppers and other insects. I was a bit surprised to hear how much of a problem leaf-hoppers can be, and that much of the insecticides used on potatoes are directed against them specifically. Potato bugs are the other big one; them I know about. My neighbours breeding project is pesticide-resistant potato bugs. Duane deals with potato bugs the same way I do: regular hand picking. That won`t work for commercial growers though, so he is also looking for plants with resistance to potato bugs, possibly ones that don't taste as good to the bugs so they go elsewhere for lunch. There are differences among varieties for this trait.
When we were finished in the primary seed grow-out garden, Duane hauled us off to the field representing one of the next stages, where the full rows of potatoes were being grown.
Here his girlfriend, Vita Gaike, had started a fire and roasted some potatoes for us, in the Latvian harvest tradition (she`s a Latvian barley breeder herself). The potatoes were from his Ruby Gold mutations (Ruby Gold White A, to be precise), and they were delicious and just the thing on a cool rainy afternoon.
Once we were done, Duane fielded some questions. Someone asked about low-glycemic potatoes, and I was interested to hear that it depends more on how potatoes are cooked and served than on the variety. Cold potatoes are lower on the index, as are larger pieces. So potato salad is low on the glycemic index while hot fluffy mashed potatoes are (alas) very high.
Here`s a view of the second potato field, with the bonfire, his harvester, and his storage shed in the distance.
The potatoes harvested here will go on to the 7 or 8 organic farm participants across Canada (half of them in the Prairies) who have agreed to trial them. Duane is hoping that as the project progresses they will find more people willing and able to trial potatoes.
Thanks very much to Duane and Vita for an excellent and informative afternoon. We really enjoyed it, and learned some very helpful ideas for our potato grow-outs. For further information, Duane recommended two books, The Complete Book of Potatoes (de Jong, Sieczka, and de Jong), and The Lost Art of Potato Breeding by my hero, Rebsie Fairholm. I think I shall have to get them.