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Hedychiums are multipurpose plants cultivated as ornamentals because of their multicolor and showy and scented flowers and as medicinal plants because of their essential oils that have been found to possess antimicrobial and insecticidal properties. There is often taxonomic and botanical confusion about Hedychium species and cultivars because of the apparent existence of more than one cytotype within several Hedychium species, most likely because of the ease with which these species hybridize. Nuclear DNA content (2C-DNA) was determined for the first time in 23 Hedychium species and hybrids. The 2C-values ranged from 1.70 pg to 3.98 pg. We also determined the chromosome number of one species, Hedychium stenopetalum, which was found to be diploid (2n = 2x = 34), supporting the widely held view that the basic chromosome number in Hedychium is x = 17, and the existence of different cytotypes is most probably attributable to natural hybridization. Our results should be helpful not only in clarifying the botanical and taxonomic confusion in Hedychium but also in paving the way for a sound breeding program for this increasingly important ornamental ginger. [ABSTRACT FROM AUTHOR]

Solanum aethiopicum L.is native to sub-Saharan Africa but is now found in many parts of the world. It is used for food, medicinal, and ornamental purposes. It has also been used as a rootstock for tomato and common eggplant because of its resistance to certain pathogens. However, very little is known about its genetics, so the purpose of this work was to assess intraspecific variability inS. aethiopicumvia morphological and cytomolecular characterization of 12 scarlet eggplant accessions. Cluster analysis was used for grouping the accessions using means of 27 variables. Four separate groups were found, with two groups each consisting of five accessions and two other groups each consisting of only one accession. Variability was high with flower- and fruit-associated descriptors among the accessions. Monoploid genome sizes (Cx-value), average chromosome sizes (C/n-value), and GC content were determined. Haploid genome size of S. aethiopicum ranged from 1.312 pg/1C to 1.538 pg/1C., which is close to the genome size (1.2 pg/1C) of the common eggplant. Only PI 420226 (1.538 pg/1C) was significantly different from the rest, giving credence to the theory that PI 420226 is actually aS. macrocarponaccession. GC content of S. aethiopicum accessions was about 40%. We used 18S-28S rDNA and 5S rDNA probes to study the distribution and physical position of these ribosomal genes in S. aethiopicum. These results help to better understand intraspecific variability in S. aethiopicum and can be important for the breeding and selection of this crop. [ABSTRACT FROM AUTHOR]