CHICAGO (Reuters) - U.S. agriculture groups are pushing for continuing talks with the presumptive Democratic and Republican presidential nominees in an effort to influence their farm policy positions as a slump in crop prices squeezes the sector’s profits. Representatives of about a dozen trade associations, including the American Farm Bureau Federation and the National Farmers Union, met with staffers for Democratic candidate Hillary Clinton on Friday at her New York campaign headquarters. It was the farm coalition’s first meeting with Clinton’s staff and included discussions of issues ranging from agricultural trade and labor to mandatory labels for foods containing genetically modified ingredients, attendees said on Wednesday. The meeting was the start of a push by the sector for more details from Clinton and Republican rival Donald Trump about their stances on issues affecting farmers and agribusiness. The groups are seeking a meeting with Trump’s campaign. “All of us agreed, on both sides of the table, that it is a successful meeting only if it’s the first of a number of exchanges,” said Jay Vroom, the chief executive of pesticide association CropLife America, who attended the session. The candidates’ agriculture policies are crucial, the groups say, because net U.S. farm income is forecast to drop to its lowest since 2002, largely due to a decline in grain prices. If that happens, incomes will be down 56 percent from a recent high of $123.3 billion in 2013. “With that kind of climate, we’re definitely concerned about what farm policy will look like building to the next (congressional) farm bill,” said Tom Bryant, the National Farmers Union’s membership director.     If elected, Clinton will increase agricultural production and profitability for family farms, spokesman Tyrone Gayle said. A Trump spokeswoman did not immediately respond to a request for comment. Matt Paul, a former U.S. Department of Agriculture spokesman working with Clinton’s campaign, participated in the meeting. The gathering came a day after Britain’s surprise vote to exit the European Union, which drew support from some regions with low population densities. Chandler Goule, incoming CEO of the National Association of Wheat Growers, said farm groups drew parallels to Britain’s referendum because “it’s going to be rural America that’s going to turn out for this election, that’s actually going to determine the outcome of this (presidential) election.” Now that Clinton and Trump are the presumed nominees, “it’s time to start making more detailed and more in-the-weeds-type commitments,” he said. 