The warning follows dissatisfaction with the way their Agriculture & Horticulture Development Board (AHDB) levy is calculated that they plan to vote themselves out of the organisation during its next five-yearly review.
Barlow said they hope to set up their own research organisation and plans for this were discussed a few weeks ago at an EAP seminar. "There's so much dissatisfaction among apple and pear growers at the moment that it's highly possible that there will be a very considerable vote from them to discontinue their levy," he added.
"We feel very sorry for people at Horticultural Development Company (HDC), in whom we have a great deal of confidence - they have been constrained by the statutory instrument.
"If there were to be a vote against the continuation of the existing arrangements it would be very important that some kind of alternative arrangement is put in place."
From last year, the top fruit levy became based on growers' turnover instead of the size of their orchard areas, to bring the calculation method in line with that of other levy payers.This raised the number of top fruit growers not paying a levy from 17 per cent to 53 per cent, leaving many of those remaining with a larger bill.
Sean Rickard, an agricultural economist at Cranfield University, last year reviewed the new levy calculation methods in a report commissioned by the HDC. He made several recommendations, one of which was to lower the threshold to £20,000 - equivalent to the former orchard size threshold of 2ha.
The AHDB then launched a consultation, which ended in February, asking all levy payers whether Rickard's recommendations should be implemented across the entire horticulture regime.
Barlow said: "There is not, in my view, going to be sufficient time to introduce change before the next review of the whole levy. That review will be one in which the views of all stakeholders are sought."
Kent-based grower Robert Mitchell said: "I have always been a strong supporter of research. But the change to the levy means that most of us are paying a lot more. I am not a happy grower.
"The only way you will get some of these research projects done is through a statutory levy, but the system has been messed about with so much that I really fear that at the next quinquennial review growers will vote on their feet."
Grower Nigel Bardsley, who sits on the HDC tree fruit panel, added: "(The vote) might well happen. We were told when we joined the AHDB that we would have more efficiencies, but all I can see is that it is taking more away from us before we even see the research. Growers are saying their bill is double what it was before - basically the growers will vote on their feet (come 2012)."
Neil Bragg, chairman of the HDC sector board, said in a statement: "The current levy rate calculation was set after a consultation exercise originated by Defra. Adrian Barlow would be the first to say that the industry failed to respond adequately at the time, even though he, through EAP, tried to encourage tree fruit growers to make their views known.
"The current consultation was aimed at finding out what people across all horticulture sectors think of the changes proposed by Rickard and how this might impact on businesses in other sectors if they were generally applied. As soon as the HDC board has seen the breakdown of responses at its meeting on 14 April, we will issue a full statement on the latest findings.
"In any event, no changes, should they be indicated by the consultation, are likely to happen quickly because this would require a change in the statutory instrument governing levy collection by AHDB."