Tag: reproduction in angiospermic plants

The stem part of the plant used in grafting is called as the stock.

A phytotron is an enclosed research greenhouse used for studying interactions between plants and the environment. It was a product of the disciplines of plant physiology and botany. The first phytotron was built under the direction of Frits Warmolt Went at the California institute of Technology in 1949. It was funded by the Harry B. Earhart Foundation and was officially known as the Earhart plant research Laboratory.

Plants can reproduce asexually and sexually. The vegetative reproduction is a means of rapid propagation, as sex cells are not involved, the progeny is identical to parent plant and the process is a type of asexual reproduction. Vegetative reproduction can be natural or artificial (cutting, layering, grafting or use of stocks). Cutting is commonly used artificial method of vegetative propagation. In cutting a cut portion of a plant generates a whole new plant as in Rose, Bougainvillea, Banana etc. Banana is a large perennial herb propagated vegetatively rather than sexually because nearly all cultivated varieties are seedless, and fruits develop parthenocarpically (in the absence of seed development). The principal method of banana propagation is division of suckers or pups which arise from the base of the main stem or from the underground corm. Large suckers are the preferred planting material. These are removed from vigorous clumps of banana trees with a spade when at least three feet tall, during warm months.

Grafting is a type of artificial vegetative propagation in plants. In grafting, a shoot of one plant (scion) is attached to shoot of another plant (stalk). The scion and shoot join to each other with the help of vascular cambium.

The vegetative reproduction is a means of rapid propagation, as sex cells are not involved, the progeny is identical to parent plant and the process is a type of asexual reproduction. Vegetative reproduction can be natural or artificial (cutting, layering, grafting or use of stocks). Grafting is commonly used artificial method of vegetative propagation. In grafting cut stem end (scion) of one plant is artificially tied using wet clay to another obliquely cut stem (stalk) which is still attached to roots. The cambial activity in the stalk and scion later on establishes a vascular link between two plants. Arguably the process is possible because plants lack a well developed immune system which can reject foreign grafts.

Plants can be propagated vegetatively without involving the process of sexual reproduction. The vegetative propagation can be natural or artificial. With the objective of improving crops and ornamental plants, humans have devised various methods for asexual propagation of angiosperms. Most of these methods are based on the ability of plants to form adventitious roots or shoots. Cutting, layering, grafting, cloning are few such methods. The layering process refers to growth of roots by vegetative structure of stem when covered by a layer of soil.

Vegetative reproduction means reproduction without the involvement of sex cells or gametes. The process of vegetative reproduction can be natural or artificial. Protoplast fusion and plant tissue culture are biotechnological techniques used in the propagation of plants through vegetative cells. In protoplast fusion, the protoplasm of two vegetative cells are fused thus sex cells are not involved. In tissue culture, whole plants can be grown using a small explant made up of the meristematic cell.

Cutting, layering and grafting are some of the techniques of vegetative propagation in plants. In layering, a portion of an aerial stem grows roots while still attached to the parent plant and then detaches as an independent plant. 

Grafting is the technique whereby tissues from one plant are inserted into those of another so that the two sets of vascular tissues may join together.
Layering is a means of plant propagation in which a portion of an aerial stem grows roots while still attached to the parent plant and then detaches as an independent plant.
Twin scaling is a method of propagating plant bulbs. Twin-scaling is practiced by professional growers and skilled amateurs to increase bulbs that would naturally propagate very slowly.
Plant cutting, also known as striking or cloning, is a technique for vegetatively (asexually) propagating plants in which a piece of the stem or root of the source plant is placed in a suitable medium such as moist soil, potting mix, coir or rockwool. The cutting produces new roots, stems or both, and thus becomes a new plant independent of the parent.
Thus, the correct answer is option (A), 'Grafting'.