Plant Propagation Techniques

Proper alignment of cambium tissues of stock and scion is required for a successful graft.

Callus formation takes place in micropropagation technique.

These are synonymous to runners but have longer internodes.

Male sterility is extremely useful in hybrid seed production because it prevents self-pollination, ensuring cross-pollination between desired parent lines. This technique allows breeders to produce large quantities of hybrid seeds efficiently and economically. It's not primarily used in pure line selection (which maintains homozygosity) or general crop improvement (which is broader in scope).

The tissue culture method of plant propagation, known as 'clonal propagation or micropropagation', utilises the culture of apical shoots, apical buds and meristems on suitable nutrient medium.

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Bolting is the rapid elongation of the stem followed by flowering, typically seen in biennial plants like cabbage when exposed to cold (vernalization). It's an adaptation for rapid reproductive growth. Splicing, hardening, and cloning are unrelated processes.

A piece of detached twig or shoot. The scion usually contains two or three buds, although it may contain more. When the scion is only a single bud, the form of grafting is known as budding.

Division, is a method of asexual plant propagation, where the plant (usually an herbaceous perennial) is broken up into two or more parts. Both the root and crown of each part is kept intact.

Grafting is the act of joining two plants together. The upper part of the graft (the scion) becomes the top of the plant, the lower portion (the understock) becomes the root system or part of the trunk. Although grafting usually refers to joining only two plants, it may be a combination of several.

Another type of  vegetative reproduction is the production of bulbs. Plants like onion (Allium cepa), hyacinth (Hyacinth), narcissus (Narcissus) and tulips (Tulipa) reproduce by forming bulbs.

Hardening is the acclimatization process where tissue-cultured plantlets are gradually exposed to normal environmental conditions to develop tolerance before transfer to soil.

A valuable tool for plant breeding and improvement of crop plants is hybridisation.

Tissue culture, specifically meristem culture, is the technique used to produce virus-free plants. The meristem (apical meristem) is typically free of viruses, and when cultured in vitro, it develops into a virus-free plant. This method has been successfully used for potatoes, tulips, sugarcane, orchids, and many other crops to eliminate viral infections.