HOME

TheInfoList



OR:

In
botany Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...
, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a
leaf A leaf (: leaves) is a principal appendage of the plant stem, stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leav ...
or at the tip of a
stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technology, engineering, and mathematics Stem or STEM can also refer to: Language and writing * Word stem, part of a word respon ...
. Once formed, a bud may remain for some time in a dormant condition, or it may form a shoot immediately. Buds may be specialized to develop
flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...
s or short shoots or may have the potential for general shoot development. The term bud is also used in
zoology Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and ...
, where it refers to an outgrowth from the body which can develop into a new individual.


Overview

The buds of many
woody plant A woody plant is a plant that produces wood as its structural tissue and thus has a hard stem. In cold climates, woody plants further survive winter or dry season above ground, as opposed to Herbaceous plant, herbaceous plants that die back to t ...
s, especially in temperate or cold climates, are protected by a covering of modified leaves called ''scales'' which tightly enclose the more delicate parts of the bud. Many bud scales are covered by a gummy substance which serves as added protection. When the bud develops, the scales may enlarge somewhat but usually just drop off, leaving a series of horizontally-elongated
scar A scar (or scar tissue) is an area of fibrosis, fibrous tissue that replaces normal skin after an injury. Scars result from the biological process of wound repair in the skin, as well as in other Organ (anatomy), organs, and biological tissue, t ...
s on the surface of the growing stem. By means of these scars one can determine the age of any young branch, since each year's growth ends in the formation of a bud, the formation of which produces an additional group of bud scale scars. Continued growth of the branch causes these scars to be obliterated after a few years so that the total age of older branches cannot be determined by this means. In many plants, scales do not form over the bud, and the bud is then called a naked bud. The minute underdeveloped leaves in such buds are often excessively hairy. Naked buds are found in some shrubs, like some species of the Sumac and
Viburnum ''Viburnum'' is a genus of about 150–175 species of flowering plants in the moschatel family, Adoxaceae. Its current classification is based on molecular phylogeny. It was previously included in the honeysuckle family Caprifoliaceae. The memb ...
s (''Viburnum alnifolium'' and ''V. lantana'') and in
herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of ...
plants. In many of the latter, buds are even more reduced, often consisting of undifferentiated masses of cells in the axils of leaves. A terminal bud occurs on the end of a stem and lateral buds are found on the side. A head of
cabbage Cabbage, comprising several cultivars of '' Brassica oleracea'', is a leafy green, red (purple), or white (pale green) biennial plant grown as an annual vegetable crop for its dense-leaved heads. It is descended from the wild cabbage ( ''B.& ...
(see
Brassica ''Brassica'' () is a genus of plants in the cabbage and mustard family (Brassicaceae). The members of the genus are informally known as cruciferous vegetables, cabbages, mustard plants, or simply brassicas. Crops from this genus are sometim ...
) is an exceptionally large terminal bud, while Brussels sprouts are large lateral buds. Since buds are formed in the axils of leaves, their distribution on the stem is the same as that of leaves. There are alternate, opposite, and whorled buds, as well as the terminal bud at the tip of the stem. In many plants buds appear in unexpected places: these are known as adventitious buds. Often it is possible to find a bud in a remarkable series of gradations of bud scales. In the buckeye, for example, one may see a complete gradation from the small brown outer scale through larger scales which on unfolding become somewhat green to the inner scales of the bud, which are remarkably leaf-like. Such a series suggests that the scales of the bud are in truth leaves, modified to protect the more delicate parts of the plant during unfavorable periods.


Types of buds

Buds are often useful in the identification of plants, especially for woody plants in winter when leaves have fallen. Buds may be classified and described according to different criteria: location, status, morphology, and function. Botanists commonly use the following terms: * for location: ** , when located at the tip of a stem (apical is equivalent but rather reserved for the one at the top of the plant); ** axillary, when located in the axil of a leaf (lateral is the equivalent but some adventitious buds may be lateral too); **
adventitious Important structures in plant development are buds, shoots, roots, leaves, and flowers; plants produce these tissues and structures throughout their life from meristems located at the tips of organs, or between mature tissues. Thus, a living plant ...
, when located elsewhere, for example on the trunk or roots (some adventitious buds may be former axillary ones that are reduced and hidden under the bark, while other adventitious buds are completely new formed ones). * for status: ** accessory, for secondary buds formed besides a principal bud (axillary or terminal); ** resting, for a bud that forms at the end of a growth season, and then lies dormant until the onset of the next growth season; ** dormant or latent, for buds whose growth has been delayed for a rather long time. The term is usable as a synonym of ''resting'', but is better employed for buds waiting undeveloped for years, for example epicormic buds; ** pseudoterminal, for an axillary bud taking over the function of a terminal bud (characteristic of species whose growth is
sympodial In botany, sympodial growth is a bifurcating branching pattern where one branch develops more strongly than the other, resulting in the stronger branches forming the primary shoot and the weaker branches appearing laterally. A sympodium, als ...
: terminal bud dies and is replaced by the closer axillary bud, for examples
beech Beech (genus ''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to subtropical (accessory forest element) and temperate (as dominant element of Mesophyte, mesophytic forests) Eurasia and North America. There are 14 accepted ...
,
persimmon The persimmon () is the edible fruit of a number of species of trees in the genus '' Diospyros''. The most widely cultivated of these is the Chinese and Japanese kaki persimmon, ''Diospyros kaki''. In 2022, China produced 77% of the world's p ...
, ''
Platanus ''Platanus'' ( ) is a genus consisting of a small number of tree species native to the Northern Hemisphere. They are the sole living members of the family Platanaceae. All mature members of ''Platanus'' are tall, reaching in height. The type ...
'' have sympodial growth). * for morphology: ** scaly or covered (perulate), when scales, also referred to as a perule (lat. perula, perulaei) (which are in fact transformed and reduced leaves) cover and protect the embryonic parts; ** naked, when not covered by scales; ** hairy, when also protected by hairs (it may apply either to scaly or to naked buds). * for function: ** vegetative, only containing vegetative structures: a leaf bud is an embryonic shoot containing leaves; ** reproductive, only containing embryonic flower(s): a flower bud contains a single
flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...
while an inflorescence bud contains an
inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...
; ** mixed, containing both embryonic leaves and flower(s).


Image gallery

File:Alnus glutinosa bud 2.jpg, ''
Alnus glutinosa ''Alnus glutinosa'', the common alder, black alder, European alder, European black alder, or just alder, is a species of tree in the family (biology), family Betulaceae, native plant, native to most of Europe, southwest Asia and northern Africa. ...
'' bud File:Tilia platyphallos bud.jpg, ''
Tilia ''Tilia'' is a genus of about 30 species of trees or bushes, native throughout most of the temperateness, temperate Northern Hemisphere. The tree is known as linden for the European species, and basswood for North American species. In Great Bri ...
'' bud File:Buds of Fraxinus excelsior 03.jpg, Black buds of a European ash, ''
Fraxinus excelsior ''Fraxinus excelsior'', known as the ash, or European ash or common ash to distinguish it from other types of ash, is a flowering plant species in the olive family Oleaceae. It is native throughout mainland Europe east to the Caucasus and Alb ...
'' File:Quince Blossom with removed watermark.jpg, A
quince The quince (; ''Cydonia oblonga'') is the sole member of the genus ''Cydonia'' in the Malinae subtribe (which contains apples, pears, and other fruits) of the Rosaceae family. It is a deciduous tree that bears hard, aromatic bright golden-yel ...
's flower bud with spirally folded petals File:Nelumbo nucifera, also known as Indian lotus in bud stage (Image 7 of 7).jpg, Opening '' Nelumbo'' flower bud File:Coreopsis tinctoria cultivar Uptick Cream and Red 8.JPG, Opening '' Coreopsis tinctoria'' flower buds File:Vitis vinifera - bud0.jpg, ''
Vitis vinifera ''Vitis vinifera'', the common grape vine, is a species of flowering plant, native to the Mediterranean Basin, Mediterranean region, Central Europe, and southwestern Asia, from Morocco and Portugal north to southern Germany and east to northern ...
'' flower buds File:烏材(軟毛柿)Diospyros eriantha 20210331093242 04.jpg, '' Diospyros eriantha'' bud File:Flower bud of Sunflower - Helianthus.JPG, Inflorescence bud of the
common sunflower The common sunflower (''Helianthus annuus'') is a species of large annual forb of the daisy family Asteraceae. The common sunflower is harvested for its edible oily seeds, which are often eaten as a snack food. They are also used in the pro ...
(''Helianthus annuus'') File:Acanthus balcanicus.jpg, Inflorescence bud of '' Acanthus balcanicus'' File:Banksia sessilis inflorescence bud closed.jpg, Inflorescence bud of the parrot bush (''
Banksia sessilis ''Banksia sessilis'', commonly known as parrot bush, is a species of shrub or tree in the plant genus ''Banksia'' of the family Proteaceae. It had been known as ''Dryandra sessilis'' until 2007, when the genus ''Dryandra'' was sunk into ''Bank ...
'') File:Cynara cardunculus0.jpg, Inflorescence bud of cardoon (''Cynara cardunculus'') File:Bud1web.jpg, An opening inflorescence bud at left, which will develop like the one to its right


References

{{Authority control Plant physiology Plant morphology