Recent advances in maize research an a global scale

Abstract

The serious outbreak of the new "T" race of Helminthosporium maydis in the U.S.A.has emphasized the need to maintain both cytoplasmic and genetic diversity among our commercial varieties. The Comprehensive Breeding System adopted by Eastern African maize breeders is designed to maintain genetic diversity as well as to continually develop improved varieties. The three major phases are: (I) Developing breeding populations from locally adapted material, from germplasm in the centre of origin of maize in Central and South America, and from improved maize varieties developed throughout the world; (2) population improvement by efficient recurrent selection methods; and (3) efficient extraction of improved open-pollinated varieties, varietycross hybrids, or conventional hybrids for release as commercial varieties.