Identification and utilization of maize germplasm introduced from CIMMYT

132 maize germplasm materials were introduced from CIMMYT in 2008,which included 50 local germplasm collections,21 hybrids and 34 moderate materials from genetic improvement nursery of CIMMYT,and 27 inbred lines.After planting and identification process of two years,most of the introduced germplasm materials showed morphological and floral characteristics similar to CIMMYT.These germplasm materials were characterized by moderate growth period,stout stalk,good grain quality and adoption to planting model of double-cropping in Guangxi.Among them,yellow grain type material CML285 showed excellent high yield and general combining ability,and could be adapted to local climate.White grain type material CML268 also showed good characters,high yield and high heritability of spike characters.Gailiangnan 60-1 showed better grain quality and higher special combining ability than CML268,which was derived from maize inbred line Nan 60-1 and improved by CML204.Through artificial inbreeding of introduced local germplasm,hybrids and moderate materials,168 stable higher generation materials were obtained which showed high yield,good growth vigor and coordination of male and female flowers.After crossing with local elite lines,600 combinations were derived from 168 higher generation materials.Furthermore,the grain quality of local maize inbred lines was improved after hybridization with the introduced materials.These introduced maize germplasm materials enriched our maize germplasm,widened genetic base of maize breeding material and accelerated the breeding of new maize varieties in Guangxi.