Nursery and its Importance
|Nursery and its Importance|
Importance of nursery
Wastage of small and expensive hybrid seeds is reduced considerably due to better care and management.
Germination percentage can be improved by providing ideal condition in a comparatively smaller place.
The management of seedlings can be done in a better way with minimum care, cost and maintenance as the nursery area is small. Flowers with very small growth are difficult to grow without first raising the nursery.
By selecting vigorous and healthy seedlings in the nursery for transplanting, better and uniform crop growth can be obtained in the main field through better survival chances.
The duration of the crop is reduced in the main field by at least a month due to the raising of seedlings, which saves land and labour of the main field and also gives enough time for harvesting of the previous crop.
The control of insect pests, diseases and weed is easy in a nursery.
Nurseries offer great opportunities of employment to semi-skilled, skilled and unskilled human resources.
Types of nursery
Nurseries are classified on the basis of duration, plant produce and structure used.
On the basis of duration
This type of nursery is established for an ongoing project of landscaping, forest, hilly regions or in natural garden in a particular season. It may also be called ‘nursery on site’. As the name indicates, it exists for a short period or up to the completion of the targeted project. Temporary nursery fulfils the seasonal requirement of landscaping. Seedlings produced in a temporary nursery are according to target and utilised fully, and not for any type of sale. Seedlings are raised only for a season and as soon as the seedlings are transplanted, the role of nursery is over. Therefore, it is also called ‘seasonal nursery’. There are several advantages with some underlying disadvantages of a temporary nursery. Initial investment in such a nursery is very low. It eliminates transportation, so first of all, the cost of transportation is reduced; secondly, transitional shock to the seedlings is negligible. Creation of extra infrastructure is not required. The prepared plants are according to the task and utilised completely. Wastage of seedlings due to mortality is minimum.
These nurseries are established with a view to supply planting material continuously wherever required. As the name indicates, it consists of a permanent infrastructure with availability of all required inputs. Permanent nursery may also be called ‘commercial nursery’, where quality planting material is produced for sale. The reputation of the nursery depends on the quality planting material produced. Permanent nursery comprises office, store, mother blocks, nursery beds, protected structures, irrigation source, electricity, transportation facilities, packing yard, manure, cattle and machinery shed. It has a record of sale and purchase, history and record of mother plants and record of produced planting material. It requires skilled workers, supervisors or managerial staff permanently. The tools and equipment required for cultivation and propagation of plants and chemicals that are necessary for raising and development of planting material is of prime importance. It is an individual enterprise and serves as a profitable source of income to the owner. Permanent nursery requires a planned outline and management. The initial capital requirement is high.
On the basis of type of plants produced
Seedlings, root stock and scion material of ornamental plants is raised and conserved for further use. This nursery includes mother block of ornamentals, which serve for scion material in layer age, budding and grafting. Raised and flat beds of the nursery occupy seedlings of different annuals, perennials and root stocks of ornamentals. Separate block of nursery consists of vegetative and reproductive phase of bulb and tuber crops. Cuttings of different climbers and creepers are planted for rooting separately. Ornamental nursery also has many indoors and outdoor potted plants. Block of seedlings of cut flowers and loose flowers, seasonal, bonsai, climber and creepers are managed individually.
In this nursery, planting materials, like seedlings of all vegetables, rooted cuttings (asparagus, sweet potato), seedlings raised from rhizomes (ginger) and tubers (potato), bulb (onion, garlic) for seed purposes are raised and conserved.
Fruit plant nursery
In this nursery, seedlings and cuttings of root stocks, budded plants, grafts, layers and cuttings of fruit trees are raised and conserved for further use. This nursery has mother block of different fruit crops used as scion material.
Different species of trees and climbers planted in forests and used in social forestry are mostly propagated by seeds. Seedlings of big trees, like margosa, gulmohar, amaltas, kanchan, tamarind, aonla, prosofis, oak, eucalyptus, etc., are commonly found in a forest nursery.
On the basis of structure used in nursery
Open field nursery
These nurseries are established in open areas without any permanent structures. Usually raised, flat or sunken seed beds are prepared. These are vulnerable to natural environmental conditions.
Such a nursery established under protected structures, can be successfully raised.
In this type of nursery, thatched roof is constructed over the nursery beds. This protects the seedlings from damage from extreme wind, rain, temperature or hot sun, etc. It is less costly but not very effective.
Such a nursery is raised under shade-net houses. To give different amount of shade based on the crop requirement, shade-nets of different colours and mesh size are used as covering material.
The nursery is covered with plastic material to form a tunnel. It is a miniature structure, which produces greenhouse-like effect. Besides being not very expensive, it is easy to construct and dismantle. The seedlings are protected from cold, wind, storm, rain and frost. Due to modified conditions, there is better germination and plant growth.
It is a frame covered structure with polyfilm or shade-nets so that plants can be grown under partially or completely modified environment. Such structures are provided with adequate ventilation and may have temperature and humidity controlling devices.
Seedlings are raised inside the structure on raised beds, or in plug-tray, used for hardening of seedlings and tissue-cultured plants.
Plant Growth Regulators (PGRs)
It is a complex organic compound other than nutrients, which applied in minute quantities, is able to promote or inhibit growth. The use of plant growth regulators is being enhanced to manipulate flowering, growth and yield of flowering plants.
Classes of Plant Growth Regulators
Some of the Plant Growth Regulators are as follows:
In a plant, auxins are synthesised in the apical portion of stem and root. Auxins control growth through cell enlargement and influence developmental responses, such as apical dominance. Indole acetic acid (IAA), Indole butyric acid (IBA), Naphthalene acetic acid (NAA), 2,4-Dichlorophenoxyacetic acid (2,4-D) are some examples of auxin .
Cytokinins help in the transport of amino acids in plants. They promote cell division and senescence.
They control cell division and elongation in plant shoots, for example, GA3.
It is a gaseous hydrocarbon and known as a ‘ripening hormone’, for example, ethephon, ethrel.
It is, generally, considered as a ‘growth inhibitor’. Because of its effects on growth inhibition or senescence, it is also involved in metabolic activities of plant viz., abscission of leaf, response to environmental stress and fruit ripening.
Application of PGR
Growth regulators are applied in very low concentrations, i.e., in parts per million (ppm). (one milligram in one litre of water gives 1 ppm solution).
Formulation of PGR
Growth regulators may be applied in powder form or paste form or as spray solution.