enigmatic potato parents

[richt]

hi all. wonder if anyone here could help me out with something? i've got a bit of a spud breeding project planned for this year, & have been trying to trace the pedigrees of my planned varieties, mostly to try & start with a bit of genetic diversity. one of these is cara, for its blight resistance, which i've read somewhere is multi-gene, & thus potentially more durable than most. what i wondered is where this comes from? ancestry, according to wageningen universitys potato pedigree database, mostly goes back on one side to early rose/pattersons crosses plus a bit of andigena of the accession thats been used for lots of modern potatoes' eelworm resistance, but the parent on the other side is just listed everywhere i look as A 25/19. is there any way of finding out what this could be, or what its likely to be bred from? same applies to all the sarpo varieties, parents are just referred to by number, & i suspect theres a load of potentially useful information hidden in these serial numbers, but i don't know how to get at it. does anyone else?
thanks
rich

[Tom Wagner]

Rich,

First of all, thanks for signing up here at the Tater Mater forum. Glad to see others wanting to breed potatoes. I have no idea where you are located, but if you have the Cara variety of potato, you probably are not in the United States.

Cara may be popular in Europe but being it is a variety from nearly 40 years ago, those varieties are not always still circulating here.

Cara is one of those varieties that throw many red splashed or red eyes progenies. In the right crosses many purple eyes or splashes, too.

Rich, you asked about A 25/19 ....a potato that is the male parent of Cara, which at one time had good late blight resistance. 'ULSTER GLADE' is the female parent of Cara and the write ups on it indicated that it didn’t have late blight resistance at all. The question is: What is the unknown history of A 25/19? That is a good question. I don't even have the information available on the Cara crosses either.

From Wikipedia

Maincrop varieties which are very slow to develop blight include Cara, Stirling, Teena, Torridon, Remarka and Romano. Some so-called resistant varieties can resist some strains of blight and not others, so their performance may vary depending on which are around. These crops have had polygenic resistance bred into them, and are known as "field resistant". New varieties such as Sarpo Mira and Sarpo Axona show great resistance to blight even in areas of heavy infestation.

I was interested in some of the history of Cara and found this site for one:

www.irishscientist.ie/2000/contents.asp?contentxml=062s.xml&contentxsl=insight3.xsl

Contact: Leslie J. Dowley, Crop Protection & Breeding Department,
Teagasc, Oak Park Research Centre, Carlow;
E-mail: [e-mail]

I am sending Dowley an email about the unk male parent.

OAKPARK BEAUTY renamed CARA at one time during it’s history.
Oh, here is a picture of Cara...
www.europotato.org/full_image.php?image=./photos/cara_t_copy2.jpg&variety=Cara

I remember well wanting to get Cara for breeding work myself and had seen a coupe of Cara crosses in California about ten years ago…the main two were Picasso and Divina. These were off limits to me and I could not find anyone who had Cara but during the 2004 season I was able to obtain four new potato clones with Cara as a parent: Kestrel, Merlin, Argos, and Valor. I made crosses with those and the bloodlines are widespread in my TPS lines and a few tuber lines. I have not seed the super blight resistance from these sources, therefore I am not sure if the blight resistance coming from Cara is good enough here where I live.

I was reading the latest from Mr. Dowley about blights (2000) and it appears that the US 8 clone knocked the Cara badly with late blight. This is the same one we have here in Washington.
www.teagasc.ie/research/reports/crops/4148/eopr-4148.asp

The population.... September 2000 is
clearly more diverse than the early 80’s population but not yet as variable as the Mexican population. Isolates corresponding to the US-1 strain were not found and this concurs with the findings of Tooly et al. (1983). This suggests that the old population has been replaced by new fitter strains. However, the RG57 probe showed that the so called ‘super strains’ such as US-6 and US-8 were absent from the 1996 population. US-1 strains from the early 1980’s Irish population have been found to be phenylamide resistant which suggests that resistance arose here andwas present before the new migrations took over. Low levels of A2 in thepopulation suggest that it does not play a significant role

About these late blight strains...

CONCLUSIONS
A new population has completely replaced the old Irish population
Genetic diversity of the Irish population of Phythophthora infestans has
progressively increased but is still less diverse than the Mexican population.
Differences between closely related strains may have arisen from somatic
recombination
A major source of genetic variation is migration of new strains from Europe
and the UK

I visited David Shaw in Wales during October, 2009 and here is an article from him just a few months later….

www.guardian.co.uk/lifeandstyle/gardening-blog/2010/feb/04/potato-blight

If you have not suffered from late blight disease on your potatoes over the last three years, you have been very lucky. A combination of constant wetness favouring blight spread and the replacement of the old blight strains by a sinister new menace called Blue 13 has created the perfect storm. Blue 13 rots faster and worse still, knocks out many of the potato varieties we depended on to resist the blight. Varieties such as Cara, Valor, Remarka and Lady Balfour now have very little resistance left, effective only in drier years and locations. Some people have decided to give up growing their own potatoes entirely, but you can fight the blight.
F-2 families of Sarpo Mira are variable in the late blight resistance. To be expected…a re-shuffling of the genes. But I still think I have better clones for near total resistance in my other material.

My summary:
I will continue to use Cara grand-offspring and crosses of those to pursue the late blight thing for the coming years. The Sarpo series will be scattered around in more plots as well. But the major push for late blight will be with a growing array of varieites and clones that have little or no documentation provided. My diploid groups with high blight resistance will be used as male pollen parents this summer.

Tom Wagner

[rich]

thanks for setting the forum up tom, i don't think my interest in potatoes would've progressed anywhere near as fast if it wasn't for all the information to be found here. i'm in the uk, & i had no idea cara was that old. its still reasonably popular among allotmenters here, which is what i am. i'd imagine that allotment sites, with their shifting populations of amateur gardeners with diverse ideas about things like crop rotation & hygiene must be a haven for blight,though we probably have less virulent/diverse strains than you what with being smaller & further away from mexico. of the "polygenic" varieties listed, i know teena, torridon & stirling were bred at the scottish crop research institute in a project using s. demissum, phureja & another i forget the name of- i had a link set up to a brilliant article called "potato breeding at scri" but somethings happened to it & springerlink now tries to charge me 30 quid to read it. but i'd understood that demissum was used specifically for major R genes, which only confer resistance to one each of 11 blight races. maybe there is some native resistance in phureja? i 'm intrigued by your mention of blight resistant diploids, are these phureja? or stentonum? will they pollinate tetraploids & produce viable seed?
for the last few years i've mostly been growing sarpos, & their selfed offspring, & they are fantastic but i don't want them to be my only source of blight resistance. anyway, i'd love to hear if you get anything back from leslie dowley.

[markl]

Hi all, I'm often curious about finding the parents of numbered lines. Is it worth the trouble? Going back a generation or two might be difficult to recover the desired genes, and those lines probably are not available anyway. I understand the thinking behind it, I do look too, hoping for some ideas on breeding lines. I've listened to many blight researchers here in the USA, it sounds like there are plenty of blight resistant genes in many of the diploids, it's a matter of taking the time to screen thousands of accessions to find them. The public breeding programs don't have enough time or money to get it all done. What concerns me about late blight discussions is too many people want to use resistance as the only method of control. Even the best blight resistant varieties are only resistant, not immune. Resistant varieties should be a part of an IPM program. Since I formerly grew acres of potatoes, I'm a believer in fungicides. Anyone who doesn't want to spray can consider cultural practices, like wider row spacing to improve air circulation, or grow out and harvest the crop before serious blight weather sets in.

I enjoy reading this site, hope everyone keeps posting.

Mark

[Tom Wagner]

With new members and guests showing up all the time, I am pressed to come up with pertinent research and/or links of outside work that dovetails with my own.

Without addressing each concern....I will just throw out some information that I want to use myself for further articles I want to write.

First of all I did a search for "potato breeding at scri" and I, too, was connected with those sites that wanted money. I refuse to be drawn into that. But I did eventually came up with some nice links....

www.mrsltd.com/potatoes_varieties.asp?menuID=3
Pictures and history of some prominent UK potatoes!

www.scri.ac.uk/research/genetics/GeneticsAndBreeding/potatoes/utilisationcpc
scri research

www.scri.ac.uk/research/genetics/GeneticsAndBreeding/potatoes

www.scri.ac.uk/research/genetics/GeneticsAndBreeding/potatoes/carotenoidspotato

www.scri.ac.uk/research/genetics/GeneticsAndBreeding/potatoes/disrespotato

To identify new and potentially durable forms of resistance we utilise the Commonwealth Potato Collection (CPC) by screening accessions with contemporary and diverse P. infestans isolates. A recent screen of CPC material was conducted with a complex A1 isolate, 01-29 (race 1,2,3,4,6,7,8,10,11) and BPC06_3928A (race 1,2,3,4,5,6,7,9,10,11). Strong resistance was identified in the diploid species S. bulbocastanum, S. okadae (Figure 2, below), S. polyadenium and S. verrucosum.

I am working with those races of resistance. One stood out in the wild species and I was pleased to see okadae. Here is the okadae
www.scri.ac.uk/scri/image/Research/genetics/s_okadae_crosses.png

I have lots of TPS of this okadae that likely is also crossed with other diploids since the flowers were exposed to many other species and many, many selections of orange fleshed phureja/stenotomum multi-generational crosses. I need to get lots of other species crossed into the okadae to make them more cross –friendly parents…note the article below…

www.springerlink.com/content/12j48m33r3743167/
B

oth full compatibility and incompatibility at various sites along the pistil were observed in the S. tuberosum × S. okadae combinations; most reciprocal combinations were incompatible. Compatible genotypes produced 2n pollen. However, only a few seeds were obtained and chromosome counts could not be carried out in the hybrid progeny because seedlings died at an early stage. The pollen-pistil barriers are incomplete and can be circumvented by the appropiate choice of parents. The identification of the post-zygotic barriers will be the focus of further studies.

www.scri.ac.uk/research/genetics/GeneticsAndBreeding/potatoes/blightresistance

Recently researchers in a number of laboratories have found, mapped and cloned new R-genes in species other than S. demissum. There is much interest and debate over whether or not these R-genes will be durable, or can be deployed in a durable way. It can be argued that new R-genes should be combined with high levels of field resistance, so that the near immunity conferred by R-genes is utilised until they are defeated, then the high levels of field resistance come into operation. Our recent research has concentrated on how easily major-gene resistance can be distinguished from field resistance and how to select for high levels of field resistance, of which there is more than one type.

Some field resistance is associated with late maturity (Bradshaw et al., 2004) and cannot be utilised in earlier maturing varieties.

That last statement may be very true.

www.scri.ac.uk/research/genetics/GeneticsAndBreeding/potatoes/breedingstrategy

the above link has a neat picture of breeding procedures ….however you may bave to use it as wallpaper to view it well. www.scri.ac.uk/scri/image/Research/genetics/potrecurrentsel.png


www.scri.ac.uk/scri/image/Research/genetics/potatoes.png
shows a picture of various tuberosum x phureja crosses.

To investigate the role flavour and texture characteristics have in general acceptability, we are phenotyping a large group phureja x tuberosum diploid backcross population for volatile and soluble compounds involved in aroma and taste, for texture and appearance, and for a suite of sensory traits.

I have lots of TPS that bouncing around the genes of tuberosum and phureja. Many have the great flavors and aromas of phureja and the yields and shapes of tuberosum. I just found a stash of Orangutan, one of my clones that has orange flesh, thus the name.

I will be featuring in my website catalog these types of breeding clones.

germinate.scri.ac.uk/germinate_cpc/app/core/passport/view_species.pl?page=3&cropname=Potato

has a link to various species. I do not access this because I have the USA Potato Introduction Station for this purpose.

Torridon and Teena have numbered parents that don’t help one much if you are a pedigree nut as I am. I have used some G numbers similar to the parents of the Torridon and Teena, and No...I don't know the pedigree either!

Stirling goes back five generations with just numbered lines, therefore one can be nearly clueless about that heritage until you go back 8 generations or so.

COLORADO is a new variety fromTORRIDON x (DESIREE x PENTLAND DELL) but even then it is 9 years old and I can find no information on it. But at least I have Torridon, Desiree and Pentland Dell crosses in my program.

GALACTICA is a new variety from TORRIDON x PICASSO (Cara x Ausonia) bred in IRLAND released 2003 aka T1399/17 from TEAGASC

Oh, and BTW, I have not heard back from Teagasc...had to resend it because Dowleys email does not work.

I have been lucky enough to have used Torridon, Stirling, Teena, and other European varieties that had at one time good late blight resistance. I am finding that one must have annual evaluations of late blight resistance to in order to constantly breed the most resistant lines together and start anew with TPS seedlings each and every year. Data that is near twenty years old is near obsolete.

www.infoandina.org/system/files/recursos/Bradshaw_and_Ramsay.pdf

Nice resource to read about the R genes. I have a good assortment of the R 0-11 genes in my tuberosum/demissum collection.

I used to put my potato breeding material out with commercial growers who used fungicides, and the like to grow their crop. I have found that they are, as a group, not interested in organic breeding work for resistance to Late Blight and anything else for that matter. I had to request that they did not use chemicals on my plots and sometimes they even obliged. Commercial growers want to cut the vines down in August and I want the vines growing until November or whenever the freezes kill them. Sometimes I get a two-fer, getting frost resistance and late blight resistance at the same juncture of time.

Tom Wagner

[rich]

good bit of winter reading there! john bradshaw is the guy who wrote my lost scri article as well. speaking of which, being a bit of a stone ager in some ways i scribbled a load of stuff from that article on various bits of paper before it disappeared, not comprehensive but it might shed some light on some of those serial numbers. i've got stirling pretty well mapped out as follows;
8204a4 x 8318(6)
8318(6) = (M109-3 x 2182ef7) x (3046(1) x (M109-3 x 2182ef7))
M109s are demissum,
2182ef7 = (not in order)11-79 x (pepo x pepo x dr mcintosh x 885 x 885 x smp x phureja x (epicure x pepo)).
never found out what 3046(1) or 11-79 were, but 885 is gladstone x (demissum x phureja)
smp was, i thought, an abbreviation for simpifolium or something like that, but my computer insists theres no such thing...
i never worked out the background of pepo either, seems to crop up a fair bit in some of the things i'm growing though


on the other side,
8204a4 = M109-3 x 2182ef7 x 2182ef7 x dave

i'm missing some names/numbers, so i've called that one dave to stop things getting to brackety
dave = pentland ace x (1306a2 x (699 x the alness))
1306a2 = 885 x dr mcintosh
the alness is majestic x abundance
699 is 121(2) x (kerrs pink x phureja)
121(2) remains a mystery

there is a site here;

www.plantbreeding.wur.nl/potatopedigree/

thats very good for tracking down named, & occasionally numbered cultivars, if my attempted link doesn't work, a search containing wageningen, potato & pedigree should furnish similar results...i've got a few more scri numbers demystified as well, which i'll gladly put up if anyones interested.