The uniform assay of the PCCMCA involves the evaluation of 30 coro hybrids in 20 contrasting environments in Latin America. The results from 1990 prove the consistency of response of come coro hybrids which have remaines in the first places during three years through 51 localities: HB-85, HB-83 and XH-53, with yields up to 6000 kg/ha (27% over the control). The stability parameters confirm the fitness of this response. New hybrids from private companies and national programmes show a continuous progress in plant breeding.