types
Rising trend for specialist
types
New potato varieties continue to become increasingly
specialised and geared to specific end-user suitability. This
trend started in the fresh pre-pack sector, now it continues
to gain importance in other sectors. Edward Long reports
SKIN finish is everything for pre-pack and baking markets and breeders have been striving to reduce the risk of damaging diseases such as black dot and silver scurf.
BPC-funded NIAB work suggests their labours are starting to bear fruit.
"We have found chalk and cheese differences in susceptibility to black dot," says NIABs Simon Kerr. "Saxon is one of the most resistant and Pentland Squire the most susceptible.
"We have also found differences to silver scurf. Our work should lead to a 1-9 score on the Descriptive List."
Blight tolerance has long been tested and Mr Kerr highlights the big differences that exist. New variety Admiral copes as well as Cara with fungal pressure and many other new types have useful tolerance. But nothing has resistance, he stresses.
Recently, highly resistant Hungarian material caused a stir but this appears to have been based on a single gene so could not be relied upon for long-term protection unlike Admiral and Caras "horizontal" and broad-spectrum tolerance, he says.
Indeed, blight has already been seen on varieties using that source of resistance so hopes that at last the fungus had met its match have been dashed.
Admiral is one of a trio of new varieties that have completed three years of independent assessments.
"It is a pre-pack/general ware type with a high yield potential. It does suffer growth cracking and mishapes but is resistant to common scab, gangrene and virus," says Mr Kerr.
"Osprey is a second early/early maincrop that gives a good yield of tubers with a nice skin finish and a moderate level of outgrades. It combines a good disease resistance profile with partial pallida resistance.
"Celine is a pale red type that produces a nice sample of oval tubers with cream flesh. Although susceptible to blight it combines good resistance to common scab with partial pallida resistance."
Two new salad varieties that look interesting are Exquisa and Red Salad, he continues.
Exquisa gives a mass of relatively small oval tubers with yellow skin and flesh with excellent flavour. It is resistant to scab.
Red Salad produces an attractive sample of uniform sized eye-catching bright red tubers. They are small and slightly elongated with creamy flesh.
However, despite breeders producing super new varieties there is still strong demand in the pre-pack and baking market for old favourites such as Maris Piper and Estima.
"Theres even some resurgent interest in one of the oldest of them all, King Edward," he concludes.
New chippers could do job for pre-pack?
NIAB is testing a lot of new chipping varieties, including Markies, Cabaret, and Asterix, some of which could also prove suitable for pre-packing, predicts Mr Kerr.
Markies has three years of independent trials under its belt and is due to appear in the 2002 Potato Variety Handbook. A maincrop with a yield up to Russet Burbank and Pentland Dell levels, but not quite up to Morene levels, it has good dry matter content and promising fry colour. Ro1 nematode resistance and moderate blight tolerance is useful but it is susceptible to powdery scab and leaf roll virus.
Cabaret, in year two of independent testing, has maincrop maturity. It yields up to Piper levels with a high percentage of marketable tubers. Resistance to gangrene, powdery scab and virus Y is good but it is fairly susceptible to blight.
Maincrop Asterix is at the same stage of testing as Cabaret. It is high yielding, has good dry matters and a moderate fry colour but is susceptible to leaf roll and virus Y.
NIAB has two new Fritolay-bred crisping varieties in year three trials, and has finished testing a third, Courlan.
"Courlan is a second early that is suitable for long term storage. The others, all coded, have early maincrop maturity. All have good processing quality but are not particularly high yielding.
"These are the pick of the current bunch but we have a lot more new varieties further back in the trialing system some of which could be the commercial winners of the future."
NIAB NEWCOMERS
• Potential pre-pack: Admiral, Osprey & Celine.
• Osprey & Celine partial pallida resistance.
• Potential chippers: Markies, Cabaret & Asterix.
• Possible pre-pack use too.
Saxon seems set to score highly when BPC-funded work on black dot resistance is incorporated into the descriptive list, says NIABs Simon Kerr.