The project found high levels of folia disease and cavity spot, said Barrie Smith, senior technical officer at the Processors and Growers Research Organisation.
"This is down to growing conditions from October to November," he explained. "Mild weather followed by long wet spells and above average temperatures lent themselves to disease.
"Cavity spot is rearing its head this year and I've heard some crops are being taken up early rather than being strawed down for winter."
Growers were restricted on how to minimize problems because we were so far into the season, he added. Unhealthy-looking carrots should be harvested before disease spreads.
The Nantes trials took place in Yorkshire and were hosted by Huntapac. Full results are due in late January, said Smith.
After washing and grading, quality assessments including sugar content were carried out and samples of the produce were sent to the canners for a factory appraisal.
"Disease levels were high this year but indications are showing good varietal differences for both Alternaria and Pythium," said Smith.
"The ranking of cavity spot tolerance of VAC 44, RX 04472269, Carazzo, Nervi, and KXPC 044 is continuing to hold with Brix readings between varieties ranging from 10.2% to 7.4%."
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