President, in Rio, defends his stand on environment.

Says that President George Bush told world leaders at the Earth Summit that he had no apologies for his Administration's environmental record and called for a `prompt start' to carry out the accords that were signed. He also vigorously defended his opposition to a treaty to protect rare and endangered plants and animals . (Excerpts from speech by Bush on `action plan,' page 5; Talks in Rio wrap up principles for preserving the world's forests, by Paul Lewis, page 4.)