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Here is a compilation of essays on the ‘Buds’ for class 11 and 12. Find paragraphs, long and short essays on the ‘Buds’ especially written for school and college students.
Essay on the Buds
Essay Contents:
- Essay on the Meaning of Bud
- Essay on the Kinds of Bud
- Essay on the Modification of Buds
- Essay on the Protection of Buds
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Essay # 1. Meaning of Bud:
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Bud is a condensed young shoot in which there are shortened internodes and the leaves envelop one another (Fig. 2.30A). During development of bud, the internodes become elongated and the leaves get separated, e.g., cabbage (Brassica oleracea var. capitata of Cruciferae, Fig. 2.30B, C).
Essay # 2. Kinds of Bud:
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Buds are of different types:
A. Depends on the Organ it Develops:
1. Leaf bud. It develops into a leaf, e.g., banyan tree (Ficus benghalensis of Moraceae).
2. Stem bud. It develops into a leafy branch.
3. Flower bud. It develops into flower.
4. Mixed bud. It develops into vegetative shoot and reproductive structures (i.e., flower), e.g., apple (Pyrus malus of Rosaceae), buckeye (Aesculus ohioensis of Hippocastanaceae) etc.
B. Depends on the Position on Plant:
Depending on the position of the plant, buds are divided into two groups:
1. Normal buds, and
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2. Adventitious buds.
1. Normal Bud:
The buds developed either on the apex of the stem or in the axil of the leaves are called normal buds. Normal bud is also divided into two types: a. Terminal or Apical bud, and b. Axillary bud. The length of plant increases by the growth of apical bud, whereas the branching system depends on the activity of axillary buds.
a. Terminal or Apical Bud:
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The bud, when situated at the terminal position i.e., at the apex, is called terminal or apical bud (Fig. 2.31 A).
b. Axillary Bud:
The bud, when developed in the axil of leaves, is called axillary bud.
Based on the position and arrangement, the axillary buds are divided into three types:
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i. Alternate,
ii. Opposite, and
iii. Whorled; they give rise to different branching patterns.
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All axillary buds do not develop into branches. Some may be always active, some remain dormant, but become active when required (if the main stem is cut off, the dormant lateral bud becomes active); and the buds that fall off instead of developing into shoots are called deciduous buds.
In addition to normal bud, two or more buds may develop in the axil.
Depending on their position with respect to one another, they are of two types:
i. Collateral, and
ii. Superposed.
i. Collateral:
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When the buds are placed side by side, they are called collateral buds, e.g., brinjal (Solarium melongena), Acer sp. (Fig. 2.31 B) etc.
ii. Superposed:
When the buds are placed one above the other, they are called superposed buds, e.g., walnut (Juglans regia), Aristolochia altissima (Fig. 2.31 C) etc.
The axillary buds except the normal one are called supernumerary or accessory buds. Rarely, the superposed buds which develop a little above the axil are called extra-axillary buds.
2. Adventitious Bud:
The buds that develop from a position other than the normal one (i.e., apex or axil) are called adventitious buds.
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The adventitious buds are of three types:
a. Epiphyllous,
b. Cauline and
c. Radical.
a. Epiphyllous:
Buds which arise on leaf are called epiphyllous type, e.g., Bryophyllum calycinum and Kalanchoe spathulata (Fig. 2.32A) of Crassulaceae; Begonia sp. (Fig. 2.32B) of Begoniaceae etc.
b. Cauline:
Buds which develop from the axil, near the cut end of the stem, after seasonal pruning (i.e., pollarding) are called cauline bud, e.g., Duranta plumieri (Fig. 2.32C) of Verbenaceae.
c. Radical:
Buds which develop on root are called radical buds, e.g., palwal (Trichosanthes dioica of Cucurbitaceae), sweet potato (Ipomoea batatas of Convolvulaceae, Fig. 2.32D).
Essay # 3. Modification of Buds:
Sometime, the buds become modified to perform special functions.
These are:
1. Thorn:
Sometimes, the buds are modified into thorns for protection, e.g., Bougainvillea spectabilis of Nyctaginaceae, Duranta plumieri (Fig. 2.32C) of Verbenaceae etc.
2. Tendril:
Sometimes, the bud becomes modified into tendril for climbing, e.g., Vitis quadrangularis (Fig. 2.33A) of Vitaceae, Passiflora suberosa of Passifloraceae etc.
3. Bulbil:
Sometimes, due to storage of food, the bud becomes swollen and is called bulbil. After detachment, the bulbil produces new plant, e.g., Dioscorea bulbifera (Fig. 2.33B) of Dioscoreaceae (develops in the axil of leaves), Fourcroya longaeva of Amaryllidaceae; and Agave americana (Fig. 2.33C) of Agavaceae; Globba bulbifera (Fig. 2.33D) of Zingiberaceae (develops from floral buds), pineapple (Fig. 2.33E).
Essay # 4. Protection of Buds:
Buds sometimes require protection from extreme low or high temperature.
The buds may be protected by the following structures:
i. Scale leaves in banyan (Ficus benghalensis), jack (Artocarpus heterophyllus, Fig. 2.34A), Michelia champaca etc.,
ii. Leaf base protects as a sheath in Wormia burbizia of Dilleniaceae (Fig. 2.34B),
iii. Coating of dense hairs in jujube (Ziziphus jujuba),
iv. Coating of oil, wax or resinous matters to prevent loss of water in Aesculus indicus of Hippocastanaceae etc., and
v. Deeply seated position in the bark of camphor (Camphorum aromaticum of Lauraceae).