Professor Geoff Dixon said the group's roll-call included every prominent crop consultant in Britain, and it must make its collective voice more powerful.
Dixon, who runs GreenGene International, said: "We have the greatest concentration of knowledge in vegetable crops in the UK and to be asked to become chairman is somewhat daunting and a considerable honour."
He added: "I would like to bring to bear consultants' views on political issues and those affecting our industry from the outside."
The association's annual closed conference in Rutland was dominated by the pesticides debate and the EU proposals rumbling through Brussels, he said.
"There has been no appreciation of the practical implications for the industry of halving the availability of pesticides. This affects the economic viability of our industry.
"It will push up food prices and make it harder for growers to produce a decent crop. This is set against a background of enormous strides in reducing or eliminating use of pesticides."
He continued: "I want the profile of the association raised as a forum of substantial knowledge and experience. Our views should be respected by Westminster, Whitehall and Brussels."
Dixon, a senior honorary research fellow at the University of Reading, also said the National Horticultural Forum should "more amply represent" the vegetable sector.
"The vegetable industry is the biggest production sector of horticulture in the country and it produces more than half of horticultural GDP. We wonder whether the National Horticultural Forum has tended to be overbearing on the side of ornamentals. I would like more emphasis on our sector."