US President George W Bush plans on Wednesday to call for halting the growth of greenhouse gas emissions by 2025. The three candidates vying to succeed him have made more ambitious proposals. Here is what they are saying about environmental and energy issues: * CLIMATE CHANGE New York Sen. Hillary Clinton, Democrat - Cut US greenhouse gas emissions to 80 percent below 1990 levels by 2050 through cap-and-trade system; require all publicly traded US companies to file report on climate change risks with the Securities and Exchange Commission.