14 February 1997

Producers are ignoring basic research data

CLOSER links between all sectors to push the UK industry ahead was a common call at the PMB-sponsored Scottish Potato 1997 conference, New Markets New Technology. But basic research results which should help producers meet stringent market needs are being neglected, it emerged.

According to Eric Allen, director of Cambridge University Farm, too many ware growers still ignore the fundamental connection between seed and target markets. Key aims to allow precise specifications to be met are constant stem populations and minimal disease. "Errors and disease inoculum will damn your best efforts in management thereafter," he warned.

Depending on storage and time of planting, the number of stems and consequently tubers increases over time, explained Mr Allen. This means that similar seed rates can create quite different stem densities both between fields and seasons. "This markedly affects the grading of the crop even without any variation in yield."

Four years work at Cambridge with Estima and Cara shows that consistent populations in crops grown for specific outlets can be achieved – provided the seed is healthy and comes from a similar production cycle and storage regime, he said. "We can get some very uniform populations.

Public perception, in part- icular, makes it increasingly important to use irrigation water efficiently, he added. But compaction, which prevents this, is often overlooked. A stone separator working 40cm (16in) deep in unsuitable conditions can halve the water available to the crop. "And you wont know about it until it is too late to do anything about it." &#42

Two new storage treatments

lNew approval means Fungazil (imazalil) can now be used on ware as well as seed potatoes to control a range of storage diseases. As the first new active ingredient for ware crops since the introduction of thiabendazole, it should be particularly useful in long-term storage, where silver scurf resistance to thiabendazole is well documented, says Rhône-Poulencs Rod Ogden.

lSilver scurf is the main target for Novartiss newly approved broad spectrum seed treatment Gambit (fenpiclonil). Very flexible in application timing it offers 2-3 months in-store control, says the firms Gary Mills-Thomas. "Ask any potato grower what is the most difficult disease to control and they will say silver scurf." Unfortunately the product, to be priced "in the Monceren bracket" will not be available until July, too late for this years plantings, he adds.