Cutting Method of Vegetative Propagation

Cutting is a detached vegetative part of a plant, which on separation and planting is able to regenerate the missing parts and develop itself into a new plant. It is an inexpensive and quick method of propagation. A large number of uniform plants can be produced using few parent plants. It does not involve specialised skills. The method is named after the part of plant used for cutting, e.g., stem, root and leaf.

1-Stem cutting

Next to seed, stem cuttings are the most convenient and popular method of plant propagation. Most the cutting techniques fall into this category. A stem cutting is any cutting taken from the main shoot of a plant or any side shoot growing from the same plant or stem. There are few general considerations which helps in selection of suitable cuttings. First of all, it is essential for the cutting to have sufficient reserve food to keep tissues alive until root and shoots are produced. The shoots with high carbohydrate content usually root better. To maintain high carbohydrate content in a shoot, ringing or notching stem down to the wood are useful practices. As a general rule, cutting from young plants root better but if older shoots of the plants are cut back hard, very often they can be induced to produce suitable shoots for rooting. Broadly there are four types of stem cuttings which are as follows:

A-Hardwood cuttings:

It is simple method of plant propagation in which cuttings are made from the mature and lignified stems of shrubs and trees. Such cuttings are easy to secure and can be easily handled, stored and transplanted. This type of cutting is prepared during dormant season. Usually from one year old immature shoots of previous season’s growth. Only healthy shoots are selected and weak, fast growing shoots with long internodes should be avoided. The length of the cutting varies from 10-45 cm in length and 0.5-2.5 cm in diameter, depending on the species. usually the cutting of 25-30 cm length with pencil thickness are preferred. Each cutting should have at least 2 buds. While preparing the cutting, a straight cut is given at the base of shoot below the node while a slanting cut, 1-2 cm above the bud is given at the top of the cutting. This helps in maintaining the polarity of the shoot and if rain occurs, water does not accumulate on the tip of the cutting, which saves the cutting from fungal infection. It also helps in maintaining polarity of the cut sticks. It is often advantageous to take hardwood cutting with a heel (in temperate fruit crops), that is with a piece of old wood, attached to the base. Presence of Mallet (present in Quince) at the base of cutting should also be preferred. Similarly, stem cutting will more often root better if bases are etiolated, notched or girdled or ringed before being removed from the parent plant. After preparation of cutting, the basal portion of those cutting should be treated with root initiating hormone, especially Indole-3-butyric acid (IBA). For deciduous crop, the dose of IBA varies from 2500-5000 ppm (with maximum 10,000 ppm in difficult to root crops) while in evergreen plants it is 2000 ppm to slightly higher (5000-10000 ppm in difficult to root crops). It is generally practised in a number of deciduous fruit plants like grape, hazelnut, chestnut, fig, quince, pomegranate, mulberry, plum, olive are commonly propagated by hardwood cutting.

B-Semi-hardwood cutting

The semi-hardwood cuttings are prepared from partially matured, slightly woody shoots. These are succulent and tender in nature and are usually prepared from growing wood of current season growth. Usually those shoot, which snap clean when broken, are considered ideal for preparation of semi-hardwood cutting. The length of the cutting varies from 7-15 cm. The cuttings are prepared by trimming the branches with a straight cut below the node and removing a few lower leaves at the base and retaining 2-4 leaves at the top of the cutting. Treating the cutting with IBA @ 1000-3000 ppm (maximum 5000 ppm in difficult to root crops) before planting is beneficial for commencement of proper rooting. While planting one quarter of their length should be inserted in the soil. The best time for taking cutting is late spring to summer, when new shoots have emerged and their wood is partially matured. It is normally practised in evergreen fruit plans like mango, guava, lemon, jackfruit, olive etc.

C-Softwood cutting:

Softwood cutting is the name given to any cutting prepared from soft, succulent and non-lignified shoots which have not become hard and woody. Usually, the cutting size is 7.5-12.5 cm but it varies from species to species. Usually some leaves should be retained with this type of cutting. Before planting treatment with IBA (500-1250 ppm with maximum of 3000 ppm in difficult to root crops)is beneficial. The best time for the preparation of softwood cutting is spring to early summer. It is normally practiced in different flowering annuals like Juniper, hollyhick, lilac. But some time it is also practised in apple, pear, peach, plum etc.

D-Herbaceous cutting:

The terminal leafy portion of the stem of a plant is used for preparing herbaceous stem cutting. These cuttings are soft and succulent with length varying from 7.5-12.5 cm. These cuttings are rooted under the same conditions as the softwood cuttings, requiring high relative humidity but are liable to wilt soon if proper humidity is not maintained. Therefore, much attention is required for working with herbaceous cuttings. Herbaceous cuttings of some plants exude a sticky sap that interferes with rooting process. In such cases basal end of the cutting should be allowed to dry for few hours before planting. For proper root initiation treatment of the basal portion of the cutting with IBA @ 500-1250. It is generally practiced in flowering annuals like Geranium, poinsettia, dieffenbachia, chrysanthemum. In fruit crops it is followed in pineapple (slips and crown), and in persimmon.

2- Root cuttings

Propagation by means of root cuttings is also a simple and cheap methods of vegetative propagation in species which are difficult to propagate with other methods. In general the plants which produce suckers freely are easily propagated by root cuttings. For preparation of root cuttings, roots which are of 1 cm thick and 10-15 cm long are cut into pieces. The best time for taking root cuttings is late winter or early spring when the roots are well supplied with stored food materials but before the new growth starts. However in temperate fruits, root cuttings are prepared in the month of December and are kept in warm place in moss grass or wet sand for callusing and are then transplanted during February-March in open beds. While using root cuttings, it is important to maintain the correct polarity. Thus, to avoid their planting upside down, the proximal end of the cutting should have straight cut and distal end a slanting cut. The proximal end should always be kept up. While planting, insert the cuttings vertically so that the top is above the soil level. However, in some cases, horizontal planting gives satisfactory results as in sweet potato. Balckberry and raspberry are commercially propagated by this method. However, kiwi fruit, bread fruit, fig, mulberry, apple, pear, peach, cherry and persimmon are also propagated by root cuttings. Apart from theses different horticultural crops particularly different flowering annuals and vegetable crops also propagated by leaf cutting due to their herbaceous nature but fruit crops are rarely propagated by this particular means of propagation. However, leaf bud cutting technique is sometimes followed for the propagation of black berry, raspberry, lemon.