BUENOS AIRES (Reuters) – Thousands of Argentine farmers protested in Buenos Aires on Saturday against President Alberto Fernandez, whose policies to contain food prices to curb rampant inflation have been criticized by the agricultural sector. Argentina is one of the world’s top food exporters and the sector is key to Latin America’s third-largest economy. Protesters waved Argentinian flags and rode tractors onto a road in front of the Casa Rosada presidential palace in the capital. It is rare for farmers to protest in Buenos Aires, as they usually hold such demonstrations in rural areas. Fern…