GEORGETOWN, Guyana — Heavy rains have damaged a 350-mile jungle road that links Guyana and Brazil and threatened to cut off food and fuel supplies to communities in the region, officials said yesterday.Some bus operators have suspended service while others are traveling with heavy wooden planks to build makeshift bridges over flooded areas.The government has sent crews to repair craters on one of the South American country’s main highways, but warned it could take several days because it is raining incessantly.“It is getting crucial,” said Clarendo Lucas, administrative chairman of the peanut-growing and cattle-ranching Lethem region. “We have advised big buses and trucks not to risk it.”He warned that communities could face shortages of rice, sugar and other supplies that normally come from the coast if the rains persist and if repairs are not made.The country’s rainy season runs from April to August.