19 September 1998

SPUDS U LIKE,

SOME U DONT

Many are called, but few are chosen. Gilly Johnson asks which potato varieties are likely to make the grade.

RELENTLESS optimism has to be part and parcel of the psyche of potato breeders. Without it, theyd give up: every year many new varieties go through NIABs trialling system – but few, if any, end up on the supermarket shelves.

Instead its the familiar names which dominate retailing: the 90-year-old King Edward, 35-year-old Maris Piper, 30-year-old Desiree and 25-year-old Estima.

Why? Because although these old favourites can be temperamental and difficult to grow, they provide customers with the flavour they want. Most of the new varieties, however, dont come up to scratch in the taste department. Thats the opinion of Alan Wilson at Waitrose.

Contrary to what potato breeders might imagine, Waitrose doesnt operate a "closed door" policy on new varieties, he says. "But just because a potato looks nice and crops well, isnt a good enough reason for us to change over. Our buzzword is taste, and the breeders havent made the progress that we would like to see."

Waitrose does conduct tasting sessions for new varieties, but this characteristic is notoriously subjective. One persons top potato is bottom of the league for another.

Theres also the rivalry between the big supermarkets; if one buyer likes a new variety, he may negotiate an exclusivity deal. Not surprisingly, companies such as Caithness Potato Breeders find dealing with supermarkets a "a delicate but rewarding business", according to Ian Guindi of Caithness.

The opinions of pre-packers must also be taken into account, he adds. They want improvements in yield, appearance, agronomic features and culinary qualities, as well as taste – a tough task for the breeder.

Even if a variety receives the seal of approval from a supermarket, its no guarantee of market share. Saxon is a case in point. Although backed by Waitrose on grounds of taste, it failed to attract growers, following problems with emergence. "It shows that we cant browbeat people into growing new varieties that they dont want to grow," says Mr Wilson. "Sovereigns another example – it almost made it, but didnt yield well enough."

"I wouldnt blame potato breeders for feeling discouraged. But we should remember that the fresh potato market is declining."

One area of growth is the organic sector. Varieties with good disease resistance, and the ability to perform well under low input conditions, are required. Cara and Santé have been favoured but Mr Wilson is looking forward to welcoming new varieties with better blight resistance, and ones with earlier maturity than Cara.

"But with good management, its possible to avoid many problems. For example, weve had King Edward grown organically. Some would say this would have been impossible, given its susceptibility to blight."

Caithness Potato Breeders has two varieties which may satisfy the organic sector: Valor and Verity. Valor has excellent potato cyst nematode resistance/tolerance and blight resistance, and Verity is noted for good yields under a low input regime. It also offers exceptional blight resistance.

About a hundred potato varieties are described in NIABs 1999 potato handbook. Only a few are likely to attract significant market share – even if they win NIAB recommendation status.

"First and foremost, growers have to choose varieties that their customers will want," says Pete Saunders of NIAB. "So the recommendation system can only be a guide. But it does offer growers an independent view of a varietys characteristics, and that is critical information which they need for crop management."

REGIONAL variation characterises the first early market. The most popular varieties remain Maris Bard, Premiere, Pentland Javelin and Dundrod. Others include Rocket, Minerva, Home Guard, Arran Comet, Ostara, Ulster Sceptre and Colmo.

Although there has been some criticism of Rockets taste, growers shouldnt forget its useful PCN resistance, which includes both golden and white types of eelworm, plus its very early bolting, he says.

No new first earlies have achieved recommendation this year. But further back in the pipeline are some worth watching, says Mr Saunders.

Blush is a parti-coloured tuber bred by Scottish Crop Research Institute (SCRI), which has done well in NIABs south-west trials. But he questions whether the colouring would be acceptable in this market. "Only the consumer can tell us." Dual PCN resistance is present but has yet to be quantified for pallida (white PCN).

Velox from Germany (Solana) is a light yellow-skinned first early, and as with Premiere, has some French fry potential, but is rather susceptible to foliage and tuber blight. It has Ro1 PCN resistance.

Orla from Teagasc, Eire (Irish Potato Marketing) has light yellow flesh and oval to long oval tubers, and good resistance to tuber and foliage blight.

"In a normal season blight wouldnt be a problem with very early lifted potatoes," comments Mr Saunders. "But this season its been difficult – particularly when crops have been started off under polythene. Resistance is relevant under these conditions; Premiere is good."

THREE new varieties make their debut with provisionally recommended status on the 1999 NIAB List.

Two have high dry matter and crisping potential: Midas (PBI Cambridge) and Sunbeam (R J Cherry), leaving Caesar (ZPC) as the pre-pack and baking entrant.

The two new crispers show useful disease resistance, says Mr Saunders. Midas offers the double benefit of golden PCN resistance and high tolerance of white PCN. It also has excellent resistance to foliage blight – but is very susceptible to spraing.

"Agronomically its a good variety, and we now need to know whether Midas can produce the quality of crisp that the processors are after." Tubers are oval and white with light yellow flesh.

Caesars ware credentials are led by high yields, resistance to damage and bruising, and good skin finish – just whats needed in a pre-pack variety, says Mr Saunders. Good disease resistance is wide ranging, bar a weakness on tuber blight. It produces long oval yellow tubers, with light yellow flesh.

Further back in the trialling system are five new varieties. These include two processing candidates, Donald (Beeson Group), as a high yielding second earlier variety for French fries, and Hermes (Scottish Office Agriculture and Fisheries Department) as a crisping type, resistant to blackleg, powdery and common scab. Hermes has already won significant processor support for crisping.

Cosmos (Agrico) is a light yellow fleshed general ware and baking type, with good disease resistance and skin finish, though susceptible to potato leaf roll virus. It is resistant to damage and bruising. Harmony (Caithness Potato Breeders) has high yields and bold, oval to long white tubers with cream flesh, and good resistance to bruising, common scab and gangrene. Vivaldi (ZPC) shows good skin finish but is somewhat disease susceptible.

A NEW section on speciality use in the 1999 NIAB handbook reflects the growing interest in punnet and salad potatoes.

"The punnet trade is an expanding area, and were seeing varieties such as Maris Peer, Nicola, Charlotte and Carlingford take market share here," says Mr Saunders.

NIAB is now running trials specifically designed for salad types, using higher seed rates and earlier harvesting.

One variety, Anya (Whitworth Foods), is provisionally recommended as suited to salad use. It is compared against two new entrants, Tiffany (Caithness Potato Breeders) and Alex (Nickerson Seeds).

"Alex has blue eyes – which looks attractive although unusual. But some people may be deterred by coloured eyes in a salad type." Tiffany also has potential as an early main crop variety.

"Punnet types need good skin finish and a small tight grade size, so are better suited to land without stone or clod problems, where webs can be kept tight."

A completely different species of potato from the Andes is being used as breeding material. Growers should look out for new speciality potatoes bred from this cross, he adds.

NIAB is evaluating a number of varieties for their suitability to organic production. Blight resistance is likely to be a key asset, says Mr Saunders, and for future virus resistance when growers start using organically produced seed.

On this basis, Cara, Romano and Santé score well. Best foliage blight resistance is from Symfonia, Midas and Stirling. Further back in National List trials are some varieties from the old eastern bloc countries which appear not to suffer from blight at all.

More information on varieties for organic production will be available from NIAB next year.

Varieties for different markets

Earlies

Maris Bard, Pentland Javelin, Premiere, Arran Comet, Colmo, Dundrod, Rocket, Minerva

Crisps

Lady Rosetta, Hermes, Saturna

French fries

Russet Burbank, Pentland Dell, Maris Piper, Shepody, Premiere

Pre-pack and wholesale ware

Anna, Cara, Desiree, Estima, King Edward, Marfona, Maris Peer, Maris Piper, Nadine, Romano, Santé, Saxon, Valor, Wilja

Chip shop

Maris Piper

Bakers

Adora, Cara, Estima, Marfona, Saxon

Punnet potatoes

Maris Peer, Charlotte, Nicola, Carlingford

Salad potatoes

Pink Fir Apple, Belle de Fontenay, Linzer Delikatesse, Charlotte, Ratte, Nicola

Organics

Maris Bard, Pentland Javelin, Cara, Desiree, Remarka, Santé

Source: BPC