International Journal of Horticulture, 2017, Vol.7, No.22, 180-204
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overcome seed dormancy by studying the nutritional and physiological aspects of embryo development and by
testing seed viability. It is easy to detect mutations and to raise isogenies pure lines through haploid cultures.
Protoplasts are excellent resources used to improve a species by introducing a gene by mutant induction or by
introducing inter-specific hybrids of incompatible crosses. Nowadays, breeders can introduce genetic variation in
commercial flowers by the application of recombinant DNA technology. This technology is effective for changes
in phenotypic expression encoded by single genes such as corolla and foliage colour and texture, stem length,
scent, temporal regulation of flowering, vase life of cut flowers and resistance to biotic and abiotic stresses.
5 Plant Introduction
Plant introduction is the process of introducing plants from their growing locality. It may be introduced either
from the country of another continent (inter-continental), from another country within the same continent (intra
-continental), from another state with in the same country (inter-state) or in the different states within the country
or from another district within the same state (intra-state plant introduction). The main objectives of introducing
plant materials from outside are for use as food, wood, medicinal or industrial purpose, to study origin and
evolution of crop plants and in case of ornamentals to enrich and fulfill the aesthetic values of gardens, parks,
buildings and bungalows and for genetical improvement of economic crops through direct release, selection, as
donor parent and as breeding materials.
5.1 Organizations for plant introduction in India
National Bureau of Plant Genetic Resources (NBPGR), New Delhi is the central body of our country for
collection, introduction, expeditions, exchange and distribution of seed and propagated materials of
agri-horticultural crops. Other organizations involved in plant introduction are Forest Research Institute,
Dehradun, Botanical Survey of India. The International Board of Plant Genetic Resources (IBPGR), FAO, Rome
was established to introduce and conserve germplasms.
5.2 Different ways of plant introductions
Exploration expedition
: It is done by a team of scientists from an organization for exploratory research to the
unexplored areas within or outside the country.
Exchange
: The material is generally obtained from friendly countries either direct or through FAO offices,
USAID, Ford Foundation, Rockfeller Foundation.
Purchase or gift
: The materials may be purchased or obtained as free gifts from individuals or institutions.
Introduction of different ornamentals in India:
Among the ornamental plants, many species of orchid and
rhododendron, musk rose, begonia, balsam, globe amaranth, gloriosa lily, foxtail lily, primula, blue poppy, lotus,
water lily, clematis and wild tulips are native to India. The Agri-Horticultural Society of India, established in
1820 introduced hundreds of species and cultivars ornamental plants in India including
Bougainvillea, Dahlia,
Mussaendra erythrophylla
, annual flowering plants from different parts of the world apart from many field crops
and vegetables. The exotic flowers have mainly come from Europe, America, Africa, China, Japan and other
countries. During Mughal’s period, many ornamentals were introduced from Persia and Central Asia. The British
and Portuguese introduced various ornamentals in India from Europe and tropical America.
Among ornamental trees, species of
Acer, Acacia, Bauhinia, Brachychylon, Cervilllia, Cryptomeria, Cotoneaster,
Cupressus, Colvillea Erythrina, Eucalyptus, Lagerstroemia, Monodora, Prunus, Pyrus, Spathodera,
Tabebuia
and many other were introduced from Australia, USA, Europe and African countries. Among ornamental shrubs,
Bougainvillea, Calliandra, Nerium, Rosa
etc. have been introduced. In bougainvillea, ‘Allison Devy’, ‘Crimson
Glory’, ‘James Walker’, ‘Lady Hudson’, ‘Orange Glory’, ‘Princess Elizabeth’, ‘Rosenka’, ‘Sandiago’ and ‘Snow
White’ were introduced from Kenya and USA (Singh et al, 1993).
