THE bottom of the pool glows twilight blue. The water, seven meters deep, serves as extra protection from the cobalt-60, a radioactive isotope. A thick and intricate concrete wall prevents the radioactive particles from escaping the irradiation chamber in which the pool is contained. Researchers from the National Nuclear Agency (Batan) are using the cobalt-60 gamma ray radiation to modify wheat, a native of the subtropicsequatorial Indonesia lies