Dry weather, increasing fertilizer costs, and concerns over export rules are pushing farmers in Argentina to plant less wheat.They might plant more soybeans instead.That is causing worries in world markets because the South American nation is the world's number six exporter of wheat.Argentina's production is even more important because of the worldwide wheat shortage.Russia's invasion of Ukraine has greatly increased wheat prices.The two countries are among the world's top wheat producers.Juan Francisco Arregui is an Argentinian farmer.He told Reuters, "The season for wheat is complicated."His fields have not received rainfall in two months.He said the crop needs rain to arrive soon, but weather predictions are not promising.While there was enough water to plant the seeds, "there is not much left," he said.He added, "It means that the wheat crop is not sure by any means. We can get it started, but then we are waiting for rain."Argentina had a record wheat harvest of 22.4 million metric tons in the season that ended.