Abstract:Zea diploperennis Doebley (DP) chromosome fragments introgressed to maize ( Zea mays L. ) were identified by genomie in situ hybridization in the stable alloplasmic pure line 540 and its hybrid Fl, Yidan 6 was obtained by crossing with maize inbred line. Diaminobenzidine tetrahydrochloride (DAB) and fluorescence staining systems were utilized for detection of the hybridization signals respectively, and both of them gave almost the same results. The hybridization signals of DP elm)matin were showed on the long arms of two members for each of chromosomes 1, 2, 5, and 8 in pure line 540 and on those of only one member for each of chromosomes 1, 2, and 8 in Yidan 6. Not only located DP chromatin on the same chromosome arms but also their percentage distances from the centromeres to the hybridization sites were close to each other for chromosomes I and 2 between pure line 540 and Yidan 6. The percentage distance of the signal on the long ann of chromosome 8 was notably shorter in Yidan 6 than in 540. The differences of the signal distribution between pure line 540 and Yidan 6 were discussed.