This year could be a pivotal for many Iowa farmers, battling to turn a profit as they plant 23.4 million corn and soybean acres across the state.Financial pressure is beginning to show.Iowa farmers are leaning more on debt, with production loans climbing 39 percent to $8.4 billion over the past five years, federal bank data shows.Loans 30 days or more past due have increased 180 percent to about $84 million since 2011, Federal Deposit Insurance Corp. data shows.Even so, the delinquency rate, while pushing higher, remains near 1 percent, based on loan data provided by Ohio State University.Delinquency rates are rising from record lows to around historic averages, said Chad Hart, an Iowa State University agricultural economist.Record corn and soybean production last year helped blunt the financial drag, but farmers are paying for it this year as the glut of grain depresses prices, he said."There could be a wave of financial issues still coming in the farm sector as we continue to see low prices and the erosion of the farm financial sheet," Hart said.