International Journal of Botany1811-97001811-9719Asian Network for Scientific Information10.3923/ijb.2006.187.192Cucumeropsis mannii Naudin: Implications for Breeding and Germplasm Characterization]]>OsujiJulian O.OkoliBosa E.Heslop-HarrisonJ.S. Pat2200622Cytological and molecular cytogenetic studies were conducted on the two accessions of Cucumeropsis mannii Naudin to establish the true somatic chromosome count, investigate the occurrence and number of ribosomal RNA genes in its genome as well as investigate any cytological and cytogenetic variation in the two cultivars of the monospecific taxon. Chromosomal counts from squashed root tips stained with FLP orcein and DAPI stained mitotic chromosomes showed a somatic count 2n = 24 for this species. The chromosomes were small in size measuring 3-4.5 μm long and mostly varied from submetacentric to subacrocentric in shape. Both 18S-5.8S-25S and 5S rRNA genes were observed in the genome. Four sites, comprising two major and two minor, of 18S-5.8S-25S rRNA genes were present on four of the largest chromosomes (4.5 μm long) while two sites of the 5S rRNA genes were observed on two other individuals of the largest chromosomes. This report establishes the correct somatic chromosome count as well as the ribosomal rRNA features of this taxon. It also shows no cytological variation between the two cultivars of this species.]]>Andres, T.C.,20042004Galasso, I., T. Schmidt, D. Pignone and J.S. Heslop-Harrison,1995Vigna unguiculata (L.) Walp: The physical organization and characterization of 18S-5.8S-25S rRNA genes, 5s rRNA genes, telomere-like sequences and a family of centromeric repetitive DNA sequences.]]>91928935Gbile, Z.O.,19861986pp: 13-29pp: 13-29Gerlach, W.L. and J.R. Bedbrook,1979718691885Gerlach, W.L. and T.A. Dyer,1980848514865Gill, L.S.,1992Pages: 212Pages: 212Jeffrey, C.,19801233247King, R.C.,1974Leitch, I.J. and J.S. Heslop-Harrison,1993Hordeum vulgare).]]>36517523Maluszynska, J. and J.S. Heslop-Harrison,1993Brassica species.]]>36774781Murata, M., J.S. Heslop-Harrison and F. Motoyoshi,1997Arabidopsis thaliana by multicolour fluorescence in situ hybridization with cosmid clones.]]>123137Okigbo, B.N.,197553131150Okoli, B.E.,198438350357Osuji, J.O., G. Harrison, J. Crouch and J.S. Heslop-Harrison,1997Musa L. lines (bananas, plantains and hybrids) using molecular cytogenetics.]]>80787793Osuji, J.O., J. Crouch, G. Harrison and J.S. Heslop-Harrison,1998Musa species, cultivars and hybrids: Location of 18S-5.8S-25S and 5S rDNA and telomere-like sequences.]]>82243248Osuji, J.O.,20032003pp: 70-83pp: 70-83Pearce, S.R., G. Harrison, M. Wilkinson, D. Li, J.S. Hesslop-Harrison, A.J. Flavell and A. Kumar,1996Vicia species: Copy number, sequence heterogeneity and chromosomal localization.]]>250305315Ramchandran, C., U.S. Seshadri and R.A. Pai,19831983pp: 685685Roy, R.P., S. Saran and B. Dutt,19911991pp: 181-199pp: 181-199Schwarzacher, T., A.R. Leitch, M.D. Bennett and J.S. Heslop-Harrison,1989In situ localization of parental genomes in wide hybrid.]]>64315324Sofowora, A.,1986Thompson, H., R. Schmidt, A. Brandes, J.S. Heslop-Harrison and C. Dean,1996Arabidopsis thaliana.]]>253247252Thompson, H., R. Schmidt and C. Dean,1996Arabidopsis thaliana genome.]]>2430173022Whitaker, T.W.,1974Cucurbita.]]>1974pp: 135-143pp: 135-143Willhoeft, U.,1997in situ hybridization of ribosomal DNA to mitotic chromosomes of tsetse flies (Diptera: Glossinidae: Glossina).]]>5262267Zoro-Bi, I.A., K.K. Koffi and Y. Dje,2003Citrullus sp., Cucumeropsis mannii Naudin and Lagenaria siceraria (Molina) Standle.]]>7189199