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Read this article to learn about the role of plant biotechnology in horticulture.
In vitro culture techniques have had numerous applications to fruit crops beginning nearly 60 years ago with embryo rescue techniques for stone fruits.
Later on, the method has been applied successfully to produce commercially acceptable early-ripening peach and nectarine cultivars.
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The methods have been adapted to other crops as well, e.g. in breeding programmes to produce both early-ripening and seedless grapes.
Historically, the second application of in vitro culture methods to fruit crops was to eliminate disease causing viruses from strawberries. Meristem-tip culture has since become an integral part of virus-indexing programmes for a number of fruit crops, usually in conjunction with thermotherapy. In some cases, it has been necessary to micro-graft the meristem tip into an in vitro- grown seedling as is done for citrus.
Within the past 25 years, micro-propagation of fruit crops has become an important application of in vitro technology (Table 27.2). Strawberry was the first fruit crop for which the method was developed. Now many fruit crops are being micro-propagated commercially. More recent uses of in vitro culture emphasize application for genetic improvement of fruit crops.
These applications include production of hybrid plants from fused protoplasts, somaclonal variation and mutagen-driven changes in regenerated plants, haploids plants from anther culture and transfer of specific genes via Agrobacterium-mediated transformation.
Following methods are used to improve and multiply the horticultural crop plants.
1. Micro propagation
2. Virus elimination
3. Genetic improvement
4. Germplasm conservation
5. Haploid production
The above mentioned methods have been employed for fruit crops (Table 2) plantation crops and vegetable crops. Examples of plantation crops are—Pineapple, palms, banana, cacao (Theobroma cacao), coffee (Coffea sp), tea (Camellia sp.) rubber (Hevea brasiliensis), Vanilla (Vanilla planifolia), clove (Syzygium sp.) ginger (Zingiber officinale), turmeric (Curcuma longa), cardamom (Elleteria cardamomum). Some of these plants are produced in millions by plant tissue culture industry.
In vegetable crops, major emphasis has been given on – cabbage (Brassica oleracea), mustard (B. campestris), artichoke (Helianthus tuberosus), garlic (Allium sativum), onion (A. cepa), tomato, carrot, melon (Cucumis melo), cucumber (Cumis sativus) pepper (Capsicum annum), and watermelon (Citrullus vulgaris). Micro propagation of ornamental plants (foliage and flower plants) has become a major plant tissue culture based industry on developed and developing countries.
