Dahlia is a genus of bushy, tuberous,
herbaceous perennial plants native mainly in Mexico, but also Central America,
and Colombia. A member of the Asteraceae (or Compositae), dicotyledonous
plants, related species include the sunflower, daisy, chrysanthemum and zinnia.
There are 42 species of dahlia, with hybrids commonly grown as garden plants.
Flower forms are variable, with one head per stem; these can be as small as 2
in (5.1 cm) diameter or up to 1 ft (30 cm) ("dinner plate"). This
great variety results from dahlias being octoploids—that is, they have eight
sets of homologous chromosomes, whereas most plants have only two. In addition,
dahlias also contain many transposons—genetic pieces that move from place to place
upon an allele—which contributes to their manifesting such great diversity.
Dhalia is the national flower of Mexico.(Wikipedia)
