ARTIFICIAL VEGETATIVE PROPAGATION - CUTTING, LAYERING, GRAFTING

-
             Asexual reproduction can also be obtained by artificial means which is generally known as vegetative propagation.
            Vegetative propagation is mainly obtained through cutting, layering and mounting.
            1. Cutting:- This is the method in which suitable branches are cut into small pieces in growing season. The cut pieces are then placed in a suitable moist soil with the portion of the stem inserted in soil. The cutting soon develops roots. In case where the root does not develop easily, a little quantity of auxin (hormone) is applied on the stem where rooting should develop.
            2. Layering:- This is the method in which roots and buds are allowed to develop before the detachment of the stem part from the parent plant. There are two kinds of layering –
            (a) Mound Layering:- In this type of layering the lower branch of parent plant is lowered by bending the branch in the middle. The bend middle portion is covered with soil leaving the tip exposed. The portion covered with soil is allowed for rooting. After the formation of roots the branch is removed by cutting and planted suitably.
            (b) Air Layering:- In this type the bark is removed in the form of a ring from the aerial branch. A layer of soil is added in the wounded portion. The soil is covered by cloth a regular and continuous supply is made so that the soil remains moist. After adventitious roots are developed fully the branch is removed by cutting and planted suitably.
            3. Grafting:- This is the method in which, the cuttings called scions are inserted on another rooted plant called stock of the superior quality of the same species or of other species or genus. Some time old plants are cut near the base and the stump that remains rooted to the soil is used as stock to raise new healthy plant by inserting the scion of a young plant. The stock supply food and water to the scion while it grows.
            There are several methods of grafting –
            (a) Bud grafting:- In bud grafting a bud is removed and used as scion.
          (b) Tongue grafting:- In this method sloping a tongue shaped cuttings are made and the scion is inserted and fitted in the stock.
            (c) Wedge grafting:- In this method a ‘V’ shaped cut is made in the scion and similarly a ‘V’ shaped incision is also made in the stock.
            (d) Crown grafting:- In this method an old tree may be rejuvenated. The scions of lesser diameter are inserted in the stock of much wider diameter.

***************

Comments

Post a Comment

Popular posts from this blog

EQUISETUM - CLASSIFICATION, STRUCTURE OF SPOROPHYTE, REPRODUCTION, STRUCTURE OF GAMETOPHYTE AND FERTILIZATION

-
Image
A. CLASSIFICATION: Division – Sphenophyta     Class – Sphenopsida        Order – Equisitales            Family – Equisitaceae               Genus – Equisetum Equisetum commonly known as horsetails comprises about 25 species and is world-wide in distribution. Equisetum can grow in wide variety of habitats. Some species grow in damp and shaded places, others grow in ponds and marshes or in sandy soil, near the banks of rivers, etc. Some others are found to grow in exposed dry habitats, along the road side and railway embankments. Some of the common Indian species of Equisetum are – Equisetum debile , E. arvense , E. Diffusum , E. elongatum , etc. B. STRUCTURE OF THE SPOROPHYTE: 1. External structure:- The sporophyte, i.e., the plant body is well differentiated into – stem, leaves and roots – Stem – The stem is underground, horizontal and much branched, which often penetrates more than a meter into the soil. The rhoizome is jointed and provided with nodes and
Read more

SELAGINELLA - CLASSIFICATION, STRUCTURE OF SPOROPHYTE, REPRODUCTION, STRUCTURE OF GAMETOPHYTE, FERTILIZATION, MORPHOLOGY OF RHIZOPHORE OF SELAGINELLA

-
Image
A. CLASSIFICATION: Division – Lycophyta      Class – Lycopsida          Order – Selaginellales              Family – Selaginellaceae                  Genus – Selaginella The genus Selaginella is commonly known as “ Club-moss ” or “ Spike-moss ”. Selaginella is a large genus comprising about 700 species and is world-wide in distribution. Some species of Selaginella are found to grow in temperate regions but majority of them are found to occur in the rain forests of tropical countries. The species of Selaginella is found to grow on the ground, on damp, shaded and humid conditions. Some species are also occurs in arid regions of the world. Temperate species are found to grow on damp shaded sides of the hills. About 55 species are found to occur in India. Of these the common species are S. rupestris, S. chrysocaulos, S. pallidissima, S. jacquemonth, S. megaphylla, S. pentagona , etc. B. STRUCTURE OF THE SPOROPHYTE: 1. External structure:- The sporophyte, i.e., t
Read more

PUCCINIA - CLASSIFICATION, VEGETATIVE STRUCTURE, REPRODUCTION, ECONOMIC IMPORTANCE

-
Image
            A. CLASSIFICATION Division – Mycota       Sub-division – Eumycotina             Class – Basidiomycetes                   Sub-class – Heterobasidiomycetidae                        Order – Uredinales                              Family – Pucciniaceae                                   Genus – Puccinia             The genus Puccinia is cosmopolitan in distribution and is a parasitic fungus causing diseases on many crop plants such as wheat, barley, oats, etc., and causes great loses to the cultivated crops. Puccinia is an obligate fungal parasite and are commonly known as ‘rust fungi’ because they produce ‘rust-like’, i.e., reddish-brown coloured spores in the form of rusty spots or streaks on stems, leaf-sheaths, leaves, etc., of the host plants.             The genus includes about 3000 species. Out of these, 147 species have been reported from India. Wheat rust disease has been extensively studied in India and is found to be caused by three different
Read more