|
|
Post by gilbert on Jun 30, 2016 15:05:54 GMT -5
How would I go about starting a pea landrace? I really need to do this, because peas are always a bust for me here in Denver. There are no shoulder seasons, just winter and summer, and a period when they alternate days.
Peas don't cross much in my climate. Fooling around making dozens of crosses is too time consuming and does not match with my goals. Does anyone know where I could get hybrid seed to start off with? Seed companies only seem to sell OP seed due to the difficulty and low yield. And I need a lot of seed; at least enough to densely plant 200" of row.
|
|
|
|
Post by templeton on Jun 30, 2016 19:06:08 GMT -5
I think you've got a problem, gilbert. Getting a landrace out of selfing plant like pea where outcrosses are very rare means you will need to plant thousands of plants to get much chance of building up a population of hybrids. I don't know of anyone selling hybrid peas. Perhaps you could look at acquiring some lines that are closer to the original wild peas, in the hope they have outcrossing characteristics. Some years ago i got hold of accessions labelled Tibet and hindu kusch through a source (I no longer have contact  )- I think the John Innes Centre has these, but I don't know how you might get hold of them. Most didn't germinate, and of those that did I didn't check the flower structure. I didn't grow enough to see if they were diverse. Depending on your goal and resources there might be alternative strategies that would give a useful result. You could do a dozen or so wide crosses year 1, grow a few of the F1s from each cross, then cross these F1s in a random sort of way. Not what you wanted to do, I know, but would give rise to a really diverse hybrid swarm. 200 feet or inches? 200 feet at an inch per plant = 2400 plants. My pea seed weighs in at 400g per 1000 seeds so you need around 1 kilo or 2 pounds of seed. You might get 100 seeds off a plant (mine vary wildly, depending on vigour - perhaps others can suggest yields you might get) so 24 plants of the double cross could give you the seed you need. You've got me thinking about digging out those old seed packets, now...  No, too many projects! T |
|
|
|
Post by gilbert on Jun 30, 2016 20:41:06 GMT -5
200 feet. 2 pounds sounds about right. I knew I was facing a difficult project. Is there anyone selling breeding material? I know one can get F1s and F2s of some things, but peas might be hard.
My 200 foot row this year only produced a few gallons and only grew two feet high, should have been 6 feet. The weather is just too crazy.
As an added disadvantage, hand crosses tend to dry up and fall of in a dry climate like this.
|
|
|
|
Post by ferdzy on Jun 30, 2016 20:48:12 GMT -5
I really don't see a pea landrace as a good idea, unless they are for dried peas. The thing I have found with peas is that each variety has its exact moment of perfection, and it is a learning curve to figure it out; what the pods look and feel like, what the peas look like. If you had a bunch of differing peas grown together, how would you ever figure that out? You couldn't. That's why it's actually good that each variety of pea is pretty much homogenous.
I think you are better off looking for heat tolerance varieties of peas.
|
|
|
|
Post by templeton on Jun 30, 2016 23:51:23 GMT -5
200 feet. 2 pounds sounds about right. I knew I was facing a difficult project. Is there anyone selling breeding material? I know one can get F1s and F2s of some things, but peas might be hard. My 200 foot row this year only produced a few gallons and only grew two feet high, should have been 6 feet. The weather is just too crazy. As an added disadvantage, hand crosses tend to dry up and fall of in a dry climate like this. Are you after snows, snaps, shellies or dry? Dwarf or tall? I think Ferdzy makes a good point, a reliable true breeding line might be preferable to a diverse swarm. Finding it/creating it is the problem. You might be able to trade/bargain/contract out the first or second generation, then do the selection yourself. T |
|
|
|
Post by keen101 (Biolumo / Andrew B.) on Jul 1, 2016 13:11:28 GMT -5
Creating a landrace out of a 90% inbreeding plant like peas may be a little hard. However in my experience one of the best places to acquire peas that may still have heterozygous genes and are sometimes still segregating (where one can select from) are the Kapuler bred peas from Peace Seeds in Oregon. Joseph has an interesting project going with tomatoes which are normally inbreeding as well (at least domesticated tomatoes), so he is working on creating tomatoes that are highly attractive to bees and have open flower structures. It would be interesting if the same could be done for a crop like peas, but i'm not exactly sure how. I did have a few pea flower mutations this year that had open flowers where pollinators could easily get to, but i think they were on random plants and the trait was not on every flower on those plants, so probably just an environmental thing and not a true breeding trait. I live about 2 hours north of you gilbert, so our climates are pretty much the same give or take. So i totally know what you mean. Spring this year went quick and turned into summer. Especially for peas. So i think selecting for peas that do not have precocious yellowing / heat tolerance might be a better plan. The only peas i have right now that are still green (and have been the last few summers) are the Biskopens and Crown type peas (Salmon-flowered, Mummy White, Mummy-pea). These are older peas though, so they may not be as tasty as the newer bred ones. I am trying hard to outcross biskopens, and i think i have a few F1 peas this year between some of the crown peas which have potential. I will look into seeing if i can send you some seed later at some point that hopefully will be helpful to what you are seeking in peas. True. The first year i attempted pea crosses i had a terrible time trying it. I did learn a few things about what not to do and ideas on what to do to be more successful. 1. Don't plant peas in full sun to begin with, always plant in partial shade if possible. 2. don't do pea crosses at noon in full sun. 3. do crosses early in the morning or in the evening when it is cool. 4. Try the "flower cap method" or whatever one wants to call it that i came up with. In one of the other threads on pea crossing i came up with a method of using the male flower as a "shower cap" type of structure to allow more time for the pollen to collect on the stamen and also provide a covering similar enough to the naturally closed flower to keep the pollen from drying out. Someone made a comment that the two flowers were kissing. Regardless of how funny it looks and what you want to call it, this method seemed to have helped my crossing rate dramatically (especially for me in a climate with very dry air). 5. using crown peas makes crossing peas a lot easier as they produce all their flowers at once. |
|
|
|
Post by steve1 on Jul 1, 2016 20:38:53 GMT -5
I think keen101 (Biolumo / Andrew B.) is on the right track. The only thing I could add is to deliberately encourage pollinators. With increased stresses such as heat, pod/stigma tend to extend outside the keel whilst still fertile increasing the risk of out crosses. Recognizing your crosses and getting some significant diversity in your pea lines are your other challenges. Doing crosses outdoors is painful. Especially with 2 meter tall plants covered in flowers and a breeze blowing. A polytunnel or such if you have the room makes it so much easier. It would probably be easier to start with at least one variety that does ok in your area. keen101 (Biolumo / Andrew B.) are you referring to the stay green trait (which is probably the opposite of precocious yellowing) i.e. green cotyledon peas? |
|
|
|
Post by Joseph Lofthouse on Jul 2, 2016 0:24:34 GMT -5
It seems to me, that merely growing a genetically diverse population of peas, that you will be selecting for higher out-crossing rates... My thinking goes like this: any natural crosses that arise will carry with them some amount of hybrid vigor, therefore they are likely to be more productive, and/or to be selected by the farmer. So their relative abundance in the population should increase over time.
Supposing that there is a genotype of pea that every once in a while has exposed floral parts due to some stray weather conditions. Suppose that there are other genotypes that never have exposed floral parts regardless of weather. Again, it would seem to me that the genotype for sometimes-open would be favored, and would tend to increase in the population.
In my garden, I estimate the out-crossing rate of peas at about 1:200. So if it takes 5 years for new varieties to stabilize, then about 3% of my patch could be expected to be segregating hybrids at any given time. Perhaps more if the hybrids are more productive or more pleasing to the farmer.
I do not maintain one pea landrace. I maintain a number of different pea landraces based on the culinary traits of the landrace. For example: I grow soup peas, shelling peas, snap peas, and snow peas. I keep them separate from one another. Then I also grow a mish-mash of assorted breeding lines that aren't much good for anything other than soup peas, and/or source material for breeding projects.
When I pick shelling peas, they are all picked the same way, regardless of genotype or phenotype: Pod full and smooth. If the pod is getting a textured surface, they are too old to pick for fresh eating. It's as straight forward as can be to pick a mixed population. However!!! I am not planting snap peas, and snow peas, and shelling peas, and soup peas all in the same landrace. The shelling peas go into a landrace all by themselves. That way, picking is trivial.
About the only time I can observe a naturally occurring pea hybrid, is if the pollen donor has colored flowers and the recipient has white flowers. So when a colored flower shows up in a white-flowered landrace it's either a weed, or a cross.
This summer, I am watching my common beans carefully, to see if I can find any crosses with runner beans. The out-crossing rate of runner beans is much higher than of common beans, so if I find a hybrid, I might can select for much higher crossing rates among the offspring.
In any case, this year, I am growing at least 7 families of beans that are descended from natural crosses among common beans. I figure that by growing high numbers of offspring that are descended from naturally occurring crosses, that I am also inadvertently selecting for more promiscuous pollination.
|
|
|
|
Post by fliver on Aug 9, 2017 21:56:26 GMT -5
I think you are better off looking for heat tolerance varieties of peas. I have read that Wando is a heat resistant cultivar of pea. |
|
|
|
Post by steev on Aug 10, 2017 1:37:08 GMT -5
Very logical, Joseph; one hopes that logic prevails in natural processes; certainly would make things more manageable.
|
|
|
|
Post by gilbert on Aug 10, 2017 7:29:06 GMT -5
Thanks everyone!
I definitely don't have the patience necessary for careful pea crossing. I do, however, have a strong and diverse population of native pollinators. So I may try Joseph's suggested approach. I never thought about the fact that hybrids might have enough hybrid vigor to dominate a population over time.
|
|
|
|
Post by ferdzy on Aug 10, 2017 11:30:44 GMT -5
I think you are better off looking for heat tolerance varieties of peas. I have read that Wando is a heat resistant cultivar of pea. I tried growing Wando early in my gardening career. What I got was a whole bunch of very different peas. Pink blossoms, white blossoms, tall, short, early, late, tasty, not tasty... at the time I indignantly discarded them with the idea that I had been sent miscellaneous floor-sweepings. In retrospect, they had probably crossed with other peas like nobody's business. So if you want to cross up some peas with heat tolerance, it looks like Wando might be a good place to start. |
|
|
|
Post by imgrimmer on Aug 10, 2017 15:25:27 GMT -5
The german genebank IPK Gatersleben has some accessions of wild peas. They might be more outcrossing types than cultivated ones. But it is just a guess. e.g.Pisum elatiusI found this article saying Pisum is to 99% a inbreeding genus although there has been found a high gene flow between different subspecies. contradictory.... |
|
|
|
Post by keen101 (Biolumo / Andrew B.) on Aug 10, 2017 16:00:25 GMT -5
I got a pretty good pea harvest this year. That giant "forest" of peas that i planted may have done the trick. I also had put a soaker hose around them when i started, so keeping them hydrated may have done it too. Plus i had many segregating crosses. Would be interested in continuing to generate a good pea seed collaboration network. I was finally able to share some red-podded snaps back to Joseph. I was very happy to do so especially after his red-podded pea seeds failed and/or got left behind. I think i still owe some seeds to galina and robertb in the UK. Please send me a pm reminding me and what peas you were interested in (or minus any that you already have). I got a very interesting phenotype this year that i called "heavily-branched". I believe it was a cross between Salmon-flowered and Mummy-White. It was heavily branched and very productive. gilbert, send me a pm and i can try to send you some of the varieties i'm working with. I say go ahead and try out Wando, but it was not heat tolerant for me. I've had better luck with Virescens Mutante (originally obtained from IPK Gatersleben seed bank), Biskopens, and the Mummy types for heat tolerance. Though in the case of Biskopens and the mummys i'm wondering if that is just because they are slightly longer season peas or what. I still have some purple and yellow peas that i need to grow that templeton sent me from AU! I guess i will have to wait until next spring or something as i just ran out of pea space and time this year. Any pea varieties you want? I'm willing to try and evade the AU restrictions if you are. But that's just how i roll. In the case of true landrace peas and/or highly outcrossing peas.... I found a trait in the JIC database that supposedly has an open keel structure. This would facilitate high outcrossing, but could result in lower fertility because pollen would dry out. I saw several pollinators trying to pollinate my peas this year with frustration. Who is particularly interested in this trait?? data.jic.ac.uk/cgi-bin/pgene/Default.asp?ID=486www.seedstor.ac.uk/search-infoaccession.php?idPlant=23534 (request from JIC in UK) training.ars-grin.gov/gringlobal/AccessionDetail.aspx?id=1800646 (request from GRIN from USDA) |
|
|
|
Post by imgrimmer on Aug 11, 2017 16:11:25 GMT -5
is this trait available somehow? Could not find the purchase button |
|
)- I think the John Innes Centre has these, but I don't know how you might get hold of them. Most didn't germinate, and of those that did I didn't check the flower structure. I didn't grow enough to see if they were diverse.
No, too many projects!
