Peru will not agree to the system on patents for plants and animals that the United States proposed in a bilateral free trade agreement, ''because it does not adequately protect the wealth of Peruvian biodiversity, nor does it guarantee the ancestral rights of indigenous communities.'' This official position was expressed last week by the president of the National Institute for the Defense of Competition and Protection of Intellectual Property, Fernando Arrunátegui.

''The system proposed by the United States would allow any citizen from another country to legally appropriate the traditional pharmacological knowledge of indigenous Peruvian communities,'' he said.

''What is needed is a system of special protection, which must also protect our biodiversity,'' said Arrunátegui. Treaty negotiations have been taking place in the southeastern U.S. city of Atlanta.