BEIJING, May 7 (Xinhua) -- Biofuels, derived from crops and once a promising alternative to petroleum, have come under increasing fire in the face of a global food shortage that has spurred chaos in dozens of countries.

    Many argue that by diverting grain and oilseed crops from dinner tables to fuel tanks, biofuels are pushing up world food prices and endangering the poor.

    Moreover, a large proportion of rain forests and wetlands featuring rich biodiversity have been bulldozed and burned to make ay for crops used to produce corn ethanol, soy bio-diesel and palm oil.

    FOOD SHORTAGE, SOARING PRICES

    African Development Bank (ADB) President Donald Kaberuka has said that up to 135 million Africans have been deeply affected by the rise in food prices.

    He said food shortage in Africa now amounts to 36 million tons, and 12 African countries, in particular Guinea, Gambia, Djibouti, Egypt, Sudan and Chad, have been the hardest hit.

    Rice prices in the Asian market have almost tripled this year, with countries like Indonesia and Vietnam imposing curbs on food exports in a bid to secure domestic food safety.

    The food crisis topped the agendas of many recent regional and world gatherings, and even industrialized countries are now feeling the pinch.

    BIOFUELS BEHIND HUNGER THREAT

    Faced with surging oil prices, the United States has long strived to develop alternative energy resources.

    The country's ethanol production has quadrupled from 1.6 billion gallons in 2000 to an estimated 6.4 billion gallons in 2007, with a large part of it coming from corn.

    In December 2007, President George W. Bush signed the Energy Independence and Security Act, mandating an increase in corn ethanol production to 15 billion gallons by 2015 and 36 billion gallons by 2022.

    To ensure smooth implementation of the act, the U.S. government has promised a subsidy of 0.51 dollar per gallon of corn ethanol.

    It is estimated that corn production in the United States will stand at 332 million tons in the 2007-2008 season, with 100 million tons of that going into fuel tanks. This will inevitably cut back on market supply and push the already inflated prices higher.

    However, Washington is not alone in using crops to produce biofuels in a bid to offset pressures from tight energy supplies. Many European countries and developing economies such as Malaysia and Brazil also rely on such energies, once cheered as green and more easily available.

    VOICES AGAINST BIOFUELS

    An adviser to UN chief Ban Ki-moon urged the United States and Europe on Monday to cut down on biofuel production, or risk a worsening of the food crisis affecting millions of the world's poor.

    "We need to cut back significantly on our biofuel programs," Jeffrey Sachs, special adviser to UN Secretary-General Ban on anti-poverty goals, said at a press conference in Brussels.

    "Biofuels were understandable at a time of low food prices and large food stocks but do not make sense now in a condition of global food scarcity," Sachs said.

    In the United States, 24 Republican senators, including presidential candidate Sen. John McCain, sent a letter to the Environmental Protection Agency on Friday, urging that changes be made in last year's energy act.

    "This subsidized (ethanol) program -- paid for by taxpayer dollars -- has contributed to pain at the cash register, at the dining room table, and a devastating food crisis throughout the world," McCain said in a statement.

    Meanwhile, a sturdy fight against biofuels is also being put up by many environmentalists, who believe that they have led to the rapid shrinking of ideal carbon storehouses like rain forests, wetlands and other wildernesses, leading to increased global warming.