He told delegates: "I am flabbergasted that they think they do not need to consult with stakeholders."
He said: "Warwick has failed to engage with the horticulture industry to find out where there are opportunities for further work that can still be done."
Bragg added: "As an industry we are really undervalued. Horticulture seems to be seen as an umbrella industry on the side - they forget that horticulture is worth 20% of the total value of agriculture."
The 6th UK Onion & Carrot Conference & Exhibition was sponsored by the British Carrot Growers Association, the British Onion Producers Association, Elsoms Seeds, the Allium & Brassica Centre, Bayer Crop Science and Plant Systems.
A full report on the conference will be published in the 27 November edition of Horticulture Week.
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