Somatic chromosome differentiation in Cucumis melo L. and C. metuliferus E.Mey. ex Naudin

Abstract

Fluorescent banding with chromomycin A3 (CMA) and 4’,6-diamidino-2-phenylindole (DAPI), and fluorescence in situ hybridization (FISH) were employed to investigate the chromosome differentiation in C. melo and C. metuliferus. The chromosome number of 2n=24 was counted in the two species. Average chromosome lengths, total chromosome lengths and ranges in chromosome lengths of the two species were very similar to each other. In spite of the karyomorphological similarity, fluorescent chromosome banding pattern was quite different in each other. Unlike the C. melo, C. metuliferus had unexpected chromosomespecific CMA and DAPI bands, especially in prometaphase. In FISH, two 5S rDNA and four 45S rDNA signals were detected at the ends of chromosomes of C. melo, while two 5S rDNA and two 45S rDNA signals were detected at the ends of chromosomes of C. metuliferus.