New Scientist letter on blighted Sarpos - but was it late blight?

Today's New Scientist has a letter from Andrew Sanderson, Co Durham who grew Sarpo Una and Sarpo Mira. He says that the Sarpo varieties suffered from blight whereas the variety Kestrel was unaffected.  He makes no mention of the crop of tubers he harvested from each variety.

The blight scores recorded in the 'official' database for Kestrel is 5 for foliage blight and 3 for tuber blight (scale 1-9 where 1 is susceptible and 9 is highest resistance). On the same scale, Sarpo Mira scores 7 (foliage) and 9 (tubers); Sarpo Una foliage is 6 and tubers 5.  In our own trials we find similar results except that Sarpo Mira usually scores 8 on foliage.

 Now, what could be going on here?  Have the Sarpo varieties changed in their resistance due to evolution of the blight pathogen? Before we jump to that conclusion there are other possible explanations. The short note does not say if plants were all grown close together in a garden plot or separated spatially. Microclimate varies across even a small plot so that after rain, foliage may dry more  quickly in one microsite and slower in another. This would affect the severity of blight infection.

It is assumed that the blight was the late-blight disease caused by Phytophthora infestans. But dark spots on the leaves can be due to other diseases and pests or even to nutrient deficiency in the soil.  Sarpo Mira often shows deficiency symptoms on lower leaves that are not disease related and do not seem to affect yield.

If Andrew has an experimental bent, he could try growing the same varieties from fresh certified seed and if similar results are obtained, samples could be sent to SRT for positive identification. Even better, he could give half the seed of each variety to a friend and have them grown on a different site and compare results.

Dublin on St Pat's weekend, Potato Day in Leitrim and 6nations win

The invitation to be key speaker at The Organic Centre's Potato Day in Leitrim was the excuse I needed to cross the small pond, renew old potato friendships and develop new. It was good to eat again at Mulligan's in the Stoneybatter.  They supply an amazing range of Irish and foreign ales. Friday was a fine day and ideal for a quick survey of seed potato outlets in Co. Wicklow with Colm.  Had a quick look at Mount Usher Garden and vowed to return at leisure; not a potato in sight.
Copper spray on sale with seed potatoes - gardeners do not know how lethal this stuff is!

Dinner at Podraig Galligher's The Boxty House in Temple Bar. As you would expect, he uses substantial quantities of ware spuds and is keen to put Sarpos on the menu and grow some Sarpos as decoration for outside the restaurant.

Podraig's Potato Scratchings are made from thin slices of Boxty - scrummy.
Turf-smoked salmon with Lumper potatoes

Colm O’Callaghan drove us to Leitrim on Saturday in time for a great potato lunch.  We had a sharp audience for the Sarpo talk although I hear 6-nations game kept some at home. After much potato crack, Colm drove us back via the stunning scenery of Kinlough and Enniskillin, diving in and out of NI Co. Fermanagh – real blight (and famine) country.

Sunday was a grand day. We met farmer John Swabby-Miller at Red Cross, Co. Wicklow to see his part-harvested crop of Axona.  Although planted late, the crop grew away fast and smothered a huge weed population including thistles. The field where the Axonas were still to harvest was totally free of weeds and the test digs yielded excellent samples that Kaethe will offer to the great and the good of the Dublin food scene.  John grows a range of veg for his farmers’ market at Red Cross.  He is offering to grow plots of all the Sarpos for demonstration in the summer.

Axona samples look in excellent condition


Our lenders are due Sarpo Seed Potatoes as part of the interest we pay on the loan.  We are trying very hard to send these out this week and next so that you can get them planted as soon as possible. 

We would appreciate if growers could pay for post and package; we will let you know by e-mail how much that will be.

Crowdfunding Success to Revolutionise Potato Growing

We are delighted to announce that we have completed our Crowdfund on BUZZBNK and managed to raise £42,445.00. 

During the 90-day appeal, we rapidly achieved our first milestone of £20,000 and motored on to get fairly close to our second milestone of £50,000.  This could not have been done without all our supporters who recommended our cause to so many friends and contacts. The Buzz on twitter and Facebook was amazing.  

So, many thanks to all who supported us and especially to those contributing donations and loans. We would also like to thank the team at Buzzbnk for helping acheive our aims and to the A-Team Challenge that match-funded us to the tune of £10,000. We are working hard now to pay Sarpo-seed interest to our lenders so that they can plant the seed as the soil warms up. We wish all our growers good luck with their crops. We would be delighted to hear about your experiences with Sarpo in the field or garden and also in the kitchen.  

The production and sales team are now able to make ready for a new launch of our Sarpo varieties and for sales next winter, in as many outlets as possible.

Apologies for this blog being late.  I was in Dublin and Leitrim attending Potato Events in the run-up to St Patrick's Day.  Of this, more later.

Citizen Science - THE CROW REPORT: buzzbnk CROWdfunders' trials, 2013

Assessment of two Sarpo Clones, 2013
Before submitting a potato clone to the costly UK National Listing process, breeders gather a huge amount of information to ensure the clone they are submitting has the highest chance of being accepted.  This information covers yield, disease resistance, eating and cooking assessments, appearance and every other aspect of the clone’s performance. The National List committee judge each clone by its Value for Cultivation and Use (VCU). It also needs to be Distinct, Uniform and Stable (DUS).
Two Sarpo clones, #12 (Crow “A”) and #32 (Crow “B”), were trialled by 33 growers around the UK.  Sites were widely distributed and covered the north of Scotland to Guernsey and Belfast. A wide range of sites ensured that the two clones were exposed to different soil types, growing techniques, weather and also different strains of the UK blight population (Phytophthora infestans).  Growers were asked for their observations on blight resistance, vigour, maturity, yield, cooking and eating qualities and any other comments.  These findings are summarised below.

Resistance to Late-Blight disease
A much drier summer than in recent years resulted in blight occurring later in many areas.  Comments on blight resistance frequently mentioned that infection occurred at the time of senescence (plants stop growing and foliage turns yellow) for Crow A, which is known to be of earlier maturity than Crow B.  In general, Crow B was more blight resistant than Crow A. This supports previous results from SRT field trials.  No tuber blight was recorded in either clone.  All growers said that the foliage of non-Sarpo varieties was more susceptible to blight.

Crow A grown in Belfast showing multiple blight lesions.  Picture courtesy of Dr Louise Cooke

Yield and Appearance of Tubers
The average yield from two plants was 2.23kg for Crow A compared with 1.66kg for Crow B, based on responses from 11 growers.  Crow A was also the most uniform in shape and size and had the better skin finish according to the majority of respondents. In areas where soils condition were very dry, Crow B was often described as having rough, cracked or netted skin.  Crow A was less affected.

Yield from two plants of Crow A (left) and Crow B (right).  Picture courtesy of Alys Fowler.

Other Observations in the Garden
Common scab was a frequent problem with Crow B, an observation consistent with those in SRT field trials.  Crow A was less affected. Scab is aggravated by dry soil at the time of tuber initiation. Both clones had some reported mis-shapes and green tubers which could be corrected in commercial fields by de-stoning and deeper planting.   Slug damage was reported at low levels in both clones.  There were no reports of soft or dry rots in the harvested tubers.

Crow B showing extremely high levels of common scab and some greening.  Picture courtesy of Dr Louise Cooke

Cooking and Taste
Both clones were judged very favourably for cooking characteristics and taste.  Examples of comments on the two clones are as follows:
Crow A:
“Nice and nutty”; “as good as Kifli”; “smooth and firm and excellent as a salad potato”; “floury and good tasting”
Crow B:
“Earthy, floury and good”; “fluffy and perfect for roasting”; “good shape for chipping”, “a bit dry but good flavour”
The only wholly negative comment from one grower was that Crow B was “horrid, bitter and soapy” when boiled.

Based on the results provided by our Crowd of growers, I would recommend Crow A as the better clone to take on to the National List.  However, I would advise that the trial was repeated, as 2013 was not an ideal year to assess blight resistance in many areas.  I would also advise adding another clone, #25, to the assessment in 2014.
We already have large amount of data for Crow A and Crow B from SRT field trials.  This has been greatly enhanced by feedback from Crowdfunders in 2013.  However, before we can proceed with confidence to National List submission more information is needed for both clones.  To this end it is suggested that a standardised “score sheet” is prepared so that better observations on maturity, crop vigour and cooking qualities can be made.

Simon White, Trials and Seed Manager, SRT
Henfaes Research Centre, February, 2014

A crowd of citizen scientists at Sarpo's Potato Day

St David's Day 2014 at Henfaes Research Centre was special in several ways. Yes, there was plenty of sunshine, plenty daffodils but also a big celebration to mark our Crowdfunding success of reaching £33,000 for Sarpo Potatoes Ltd.   David Shaw welcomed thirty Crowdfunders to Henfaes to learn more about blight, the advantages of our low-input  varieties and plans for the trading company formed to bring Sarpo varieties centre stage.  Simon White told guests about seed production and how the crowd from last year had assessed two potential new varieties. David Gale outlined the structure of the new company and introduced the management team.  James Stroud gave guests a flavour of some of his research on late blight of tomato. He has characterised the strains of blight that attack tomato and those attacking potato. James is breeding varieties for outdoor growing in UK - blight-resistant varieties - in a collaborative project with Bangor University.
The crowd was sustained by potato soup (with leek), potato bread rolls and several kinds of twice baked, stuffed Sarpos (Axona and Blue Danube).  Not a morsel remained!
After lunch we discussed future plans and the crowd offered useful suggestions for branding and funding of the new company.  Simon provided seed to lenders who had earned interest and distributed seed of three potential varieties that members of the crowd will grow, observe, measure and taste.
The crowd resolved to make a final effort to grow the fund in its last 13 days of life to as near as possible to its second milestone of £50k. It was agreed that an efficient way would be for each person to email/phone/write to 10 of their most likely contacts. These would be people most likely to support a project to promote the growing of no-spray, blight-resistant potatoes - an alternative to GM blight resistant potatoes but that are available NOW.

We would like to thank all our Crowdfunders for supporting us in such useful ways.