Tag: asexual modes of reproduction

Grafting is a technique whereby tissues from one plant are inserted into those of another so that the two sets of vascular tissues may join together.
The plant that is selected for its roots is called the stock while the other plant, selected for its stems, leaves, flowers or fruits is called the scion
Thus, the correct answer is option (B), 'Scion'.

Scion is the part of the grafted plant that gives rise to the plant shoot that will, later on, produce all of the plant parts such as leaves, stems, flowers, and fruits. Everything above the scion is cut off in the spring hence all nutrients and water absorbed by the roots becomes available to the growing scion. Thus the correct answer is option C.

Vegetative reproduction is a type of asexual reproduction in which new plants are formed from the vegetative parts like, tubers, runners, suckers, rhizomes etc. Some of the plants can be propagated by the means of cutting. The part which is cut is allowed to grow into a new plant. Cane cutting which means the stem cuttings are used in the case of sugarcane. Stem cuttings with one nodal leaf are used in the coffee plants. Stem and root cuttings can be used in the Citrus species. 

A number of methods of artificial propagation of plants are used in agriculture, and horticulture. The three common methods for the artificial propagation of plants are: cuttings, layering and grafting. 

Grafting is the artificial method of vegetative propagation which is applied for plants with weak root system. It involves transfer of part of one plant (scion) onto the lower part of another plant (stock) in such a way, to facilitate organic fusion or fusion of tissues. Here, the root stock is selected for its disease resistance and absorbing capacity which makes options A and C incorrect. Since, scion makes the upper above ground portion of plant, it is selected for superior quality of fruits and flowers. This makes option D incorrect and B correct. 

The plants like rose, Bougainvillea, Chrysanthemum, grapes, sugarcane, bananas, and cactus, etc. can be grown by means of cuttings. For example, rose plants and chrysanthemums are propagated (or reproduced) by means c cuttings from stems (or shoots) as follows: A piece of stem (or side shoot) having bud is cut from an existing rose plant with the help of a knife. The lower part of this gutting, is buried in moist soil. After a few days, the end of cutting buried in soil develops roots and later on grows to become a new rose plant. 

The plants can be reproduced asexually by the method of vegetative propagation using the parts of the plants. The rose can be propagated by stem cutting. The stem can be cut with a bud and used for the growth of new plants. There are many plants which can be propagated through stem cuttings like sugar cane and guava.

A small part of a plant which is removed by making a cut with a sharp knife is called as a 'cutting'. A cutting may be a piece of stem, root or even a leaf. While making a cut, care should be taken to see that there are some buds on it. In this method, a cutting of the parent plant having some buds on it is taken and its lower part is buried in the moist soil. After a few days, the cutting develops roots; shoot, and grows into a new plant.