Vegetative propagation is a form of asexual reproduction and in this process; a new plant grows from a fragment or cutting of the parent plant or specialized reproductive structures. It can occur naturally or artificially. Although most plants normally reproduce sexually but have the ability to propagate vegetatively if small pieces or cuttings are subjected to chemical(hormonal) treatment. It is because meristematic cells which are capable of cellular differentiation are present in many plant tissues. Success and loss rates of propagation vary greatly. On the other hand, monocotyledons, unlike dicotyledons, typically lack a vascular cambium and are, therefore, harder to propagate. Vegetative propagation is generally performed to preserve the pure cell line of the plant. Any part of the plant (root, stem, or leaf) that produces roots when put in the soil eventually gives rise to a whole plant which is exactly similar to the parent plant is known as cutting. Cutting is the most important means of propagating ornamental shrubs, deciduous species as well as the broad and narrow-leaved types of evergreen. For proper rooting of the cuttings, it is important that the medium used for propagation ensures enough supply of oxygen and moisture. Media such as sand, peat, sphagnum moss, or coconut fibers are suitable media for cutting. There are different kinds of cutting such as stem cutting that includes hardwood cutting, semi-hardwood cutting, softwood cutting, herbaceous cutting; leaf-bud cutting, leaf-cutting, and root cutting. Several factors affect cutting such as internal factors that include food supply, sex of plant, age of the rootstock, time of collection, presence of foliage on cutting, flowering or vegetative wood, type of cutting, treatment of cutting, wounding of cutting, and external factors that include moisture retention, humidity, temperature, light, rooting media. Dendrocalamus strictus is a native to India where it occupies 53% of the total bamboo area (between the Ganges and Ramayana rivers). It is also native to Nepal, Bangladesh, Myanmar, and Thailand. Bamboos can be vegetatively propagated through rhizomes, culm cutting, and branches or through seed propagation. This species is mainly found in semi-dry and dry deciduous forests or as an understory in mixed forests and teak plantations. Bamboo is known for its commercial as well as medicinal value. It exhibits both physical and mechanical properties.

In spring, the leaves and new shoots of bamboos start to grow when the temperature rises and there is enough moisture in the soil. Cutting was taken a while before this new growth started when the buds were getting ready to burst.

Using a kni    fe or sharp scissors, 5-10 inch sections of bamboo were cut at a 45° angle from a healthy bamboo plant. It was made sure that there were two nodes and internodes in each section cut.

A node is the hard growth which encircles the bamboo cane, separating it into sections. The green sections between the nodes are referred to as internodes.

It is important that the ends of the cuttings are kept wet during transportation. After loading into the dokos, they were covered with wet straw or sacking or any material that was available to retain the moisture and to protect the cuttings from the abiotic factors such as the sun and the wind. A container of water was carried with the cuttings as the cuttings were to be taken far to keep them moist.

A tray was filled with the potted soil of high quality. With the help of long wooden spoon, evenly sized holes were made in the potted soil. The propagating trays used can be of metallic (iron) or plastic.

Plant growth regulator most reliable in stimulating adventitious root production in cuttings is auxin. IBA was taken for this purpose. IBA was prepared at the concentration of 4,000ppm with ethyl alcohol (75%). The top edges of the D. strictus were dipped into the soft wax, keeping the center hole of the bamboo cutting exposed. It kept the bamboo from drying out as the root development paced. The bottom of the cuttins were dipped into the rooting hormone. Bamboo cuttings were shook gently to remove any excess rooting hormone.

Cuttings of D. strictus were placed into the holes in the potted soil in the growing tray, bottom sides pressed the soil firmly into place, eliminating any air pockets that may have formed around the bamboo cuttings. Afterwards, the water was poured into the center of each bamboo cutting until the section was full.

Trays were transferred to the mist chamber and were regularly sprinkled with water but not soaking wet. Mist chamber was properly aired for about 1 to 2 hours everyday for proper aeration.

Observation and Result

After following the method of propagation, the cuttings were transported to the mist chambers that were examined continuously. The roots appeared within seven weeks after plantation of the cuttings in the trays. Formation of roots at the bottom of the cuttings showed the appropriate usage of growth hormone, i.e., Indole-3-butyric acid. IBA induced the formation of root initials in the cuttings that showed positive effect on the Dendrocalamus strictus root growth.

According to the work of Ray and Ali. 2017, the vegetative propagation of bamboo via culm cutting was found to be the simplest and most cost-effective method developed over the last few decades. The demand for bamboo has increased over time due to its multipurpose utility as to the data given by Goyal et.al. 2010. Human activities such as deforestation, industrialisation and illegal extraction of bamboo have resulted in the loss of natural bamboo resources (Subramanian, K.N. et.al. 1998, Roy et.al. 2014). Therefore, it is necessary to find cost-effective method for large scale propagation of bamboo for planting new bamboo forests to reduce the existing gap between demand and supply. The interactions of species, auxins and seasons still need to be studied thoroughly. According to the research conducted by Gulabrao et.al. 2011, exogenous application of growth regulators mainly auxins has been reported to positively influence induction and growth of adventitious roots in culm cuttings in bamboo.

Advantages of vegetative propagation are that the offsprings are genetically identical and therefore, adnantageous traits can be preserved. In this method, only one parent is required which eliminates the need for special mechanisms for sexual reproduction such as pollination and so on. Many plants and trees are able to tide over unfavourable conditions because of the presence of organs for asexual reproduction like tubers, corms, bulbs, etc. vegetative propagation is most beneficial to the agriculturists and horticulturists. Along with advantages of vegetative propagation there are some disadvantages also. The plants gradually lose their vigour as there is no genetic variation. They are more prone to diseases that are specific to the species. No new variety can be evolved by the means of vegetative propagation. Plants propagated by vegetative means are comparatively short lived. Lack of tap root system in vegetatively propagated plants results in the poor anchorage in the soil due to which they are easily uprooted in storms and other such severe conditions. Vegetative propagation in many cases is more expensive than seed propagation. It is a specialized job and requires special training and knowledge on the part of the plant propagation.