International Journal of Horticulture, 2017, Vol.7, No.22, 180-204
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clematis (
Clematis montana
- a climber) and the wild tulip of the Himalayas (
Tulipa stellata
and
T.aitchisonii
).The important native ornamental flowering trees, mentioned in ancient literature are Kachnar
(
Bauhinia variegata
), Amaltas (
Cassia fistula
), Pink cassia (
Cassia nodosa
) Dhak or Flame of the Forest (
Butea
frondosa
), Indian coral tree (
Erythrina blakei
, Pride of India (
Lagerstroemia flos-reginae,L. thorelli
), Lal Lasora
or Scarlet Cordia (
Cordia sebestena
), Yellow silk cotton (
Cochlospermum gossypium
), Karanj (
Pongamia
glabra
), Rugtora or Wavy-leafed Tecomella (
Tecomella undulata
), tulip tree or Bhendi (
Thespesia populnea
),
Crataeva roxburghii
,
Sterculia colorata
, chalta (
Dillenia indica
), Ashoka, Kadamba and rhododendrons. Among
the shrubs and climbers originated from India are the jasmine (
Jasminum sambac
,
J.pubescens
,
J.auriculatum
,
J.humile
,
J.officinale
,
J.grandiflora
) and madhavi (
Hiptage medablota
), which have been mentioned by Kalidasa
in his plays. The other indigenous species are
Bauhinia acuminata
,
Mussaenda frondosa
,
Ixora spp.
(
I. coccinea,
I. parviflora
,
I.barbata
,
I.undulata
),
Hamiltonia sauveolens
,
Holmskioldia sanguinea
,
Clerodendron inerme
,
Crossandra infundibuliformis
,
Plumbago rosea
,
Plumbago zeylancia
,
Tabernaemontana coronaria
,
Trachelospermum fragrans
,
Osmanthus fragrans
,
Passiflora leschenaulti
,
Clitoria ternatea
,
Porana paniculata
,
Gloriosa superba and Clematis montana
.
Globally, most of ornamentals are confined to north-eastern Eurasia. There are about 8000 species of ornamentals
in world trade for commercial purposes. Amongst them
, Gladiolus, Iris, Narcissus, Rosa, Tulipa
are grown over
large areas. Out of 120 perennial plants, paeony, phlox, iris, lily, tulip and daffodil and 100 annual species, china
aster, petunia and marigold showed greater diversity. Basilevskaya (1960) first investigated the geographical
origin of garden plants. Coats (1968) who first traced out the ornamental herbs whereas Hui-Lin Li (1974) wrote
first introduction of woody plants. There are altogether thirteen centres of origin of identified for ornamental
plants as given below.
The Mediterranean Centre
: It covers about 1000 ornamental species i.e. 20% of garden plants and amongst
them, daffodil, hyacinth, cyclamen, stock, iris, garden pansy, oleander, cornflower, windflower, paeony are
common.
The North American Centre
: It envisages about 650 native species or about 13% of garden plants of the world.
Popular ornamentals include white acacia,
Phlox paniculata
, perennial lupin (
Lupinus polyphyllus
), cone flower
(
Rudbeckia hybrida
), coreopsis, evening primrose (
Oenothera
spp.), purple coneflower (
Echinacea purpurea
).
South African Centre
: This is a good source of ornamentals covering 600 species or about 12% of garden plants.
Popular ornamental species originated from this centre are bird of paradise (
Strelitzia reginae
), cape
primrose(
Streptocarpus hybrida
), belladonna lily(
Amaryllis belladonna
), Giant summer hyacinth (
Galtonia
candicans
), geraniums(
Pelargonium
), gladiolus, crassula, gasteria, haworthia, gazania.
The Meso-american Centre
: (Southern Mexico and Central America). There are about 500 ornamental plant
species or about 10% of garden plants of the world available in this centre. Those are cacti (
Opuntia,
Echinocereus, Mammilaria
etc,), orchids (
Odontoglossum, Oncidium, Vanilla
), begonia (
Begonia imperialis
),
Cosmos bipinnatus
, Dahlia,
Gomphrena haageana
, marigolds (
Tagetes erecta
,
T.patula,
T. tenuifolia
), floss
flower (
Ageratum houstonianum
),
Cemmelina tuberosa
and
Zinnia elegans.
Tropical Asian Centre:
(Indo-Malayan Centre). This centre has originated about 450 ornamental species or 8%
of garden plants. Amongst them, orchids, begonias (
Begonia rex
), Indian Rubber Tree (
Ficus elastica
),
Aglaonema, Codiaeum, cockscomb (
Celosia argentea
), globe amaranth (
Gomphrena globosa
), and balsam
(
Impatiens balsamina
).
The European Centre:
There are about 300 ornamental plant species native to Europe. Common ornamental
plants derived from this centre are
Adonis vernalis
, common daisy (
Bellis perennis
), horned violet (
Viola
corunata
) and sweet violet (
Viola odorata
).
