Glossary of Terms
Cacti-Related Terms and Definitions
http://cactiguide.com/glossary/
This glossary of cacti-related terms was put together by CactiGuide.com forum moderator,
John Chippindale of Leeds England.
Abaxial
Turned away from axis; referring to surface of an organ, such as a leaf,
facing away from the main stem (opp. Adaxial).
Acauline
Stemless; sometimes only appearing to be without a stem where this is
hidden below soil level.
Acicular
Shaped like a needle, Cactus spines are often Acicular
Acropetal
In the direction of the apex, referring to developmental sequence.
Acrotonous
Emphasised towards the apex.
Actinomorphic
Radially symmetrical; referring to a flower with more than two planes of
symmetry (see Zygomorphic)
Acuminate
Tapering to a point.
Acute
Pointed.
Adaxial
Towards the axis; referring to the surface of an organ facing towards
the main stem (opp. Abaxial).
Adventitious
Said of the roots which do not arise from the radicle or primary root
system, but from elsewhere
Adventitious buds
Buds appearing in an unusual place; for example, buds on leaves
(Example: Kalanchoe ), or buds arising from the vascular bundles not,
as we might expect, from the areoles, generally in response to an
injury
Aerial root
Root arising above the ground.
Alternate
Of leaves or other parts not opposite or whorled but placed singly at
different heights on the stem.
Anastomosing
Connecting to form a network, especially veins in a leaf.
Anatrapous
Inverted, recurved through 180; said of an ovule bent over against its
own stalk, with the mouth or micropyle close to the placenta.
Annulate
Ringed or banded.
Annulus
The raised ring around the centre of a succulent flower.
Anther
Male part of the flower that produces pollen, usually borne on a
filament. Anther and filament together are known as a stamen.
Anthesis
The period of time in which a flower is open.
Anthocyanin
Blue, violet or purple pigment colouring leaves etc.
Anticlinal
Said of the cell-walls which cut the surface at right angles (opp
Periclinal).
Apex
Tip, the highest point.
Apical
Located at or constituting the apex.
Appressed
Lying flat pressed closely against the surface.
Areole
Highly condensed and modified short-shoot growing in the leaf axil as
a felted cushion, unique to cacti, usually hairy and/or spiny; from them
the flowers and offsets arise.
Aril
Outer covering or merely an appendage of a seed formed from the
funicle; may be pulpy or hard.
Ascending
Nearly erect.
Autogamy
Self-fertilisation or self-pollination.
Axil
Notch or angle between the axis and any organ, e.g. leaf, arising from
it.
Betalain
Nitrogen-containing pigment found only in the group of families,
including Cactaceae known as Centrospermae.
Binomial
nomenclature
In biology the binomial nomenclature is a standard convention that
identifies each species by a scientific name of two words, Latin in form
and usually derived from Greek or Latin roots. The scientific name of a
species is formed by the combination of two terms The first name
(capitalized) is the genus of the organism, the second (not capitalized)
is its species. The scientific name of the Yellow alicoche hedgehog
cactus is Echinocereus papillosus, while the Claret-Cup Hedgehog
cactus is Echinocereus triglochidiatus. The first name applies to all
species of the genus, Echinocereus is the name of all hedgehog cacti,
but the entire binomial applies only to a single species. Many scientific
names describe some characteristic of the organism (as: papillosus =
with papillae; triglochidiatus = with three bristles); many are derived
from the name of the discoverer or the geographic location of the
organism. Genus and species names are always italicised when
printed; the names of other taxa (families, etc.) are not. The genus
name can be abbreviated to its initial letter (as E. triglochidiatus) when
repeated or when several species from the same genus are being
listed or discussed in the same paper or report. Subspecies are
indicated by a trinomial; The advantages of scientific over common
names are that they are accepted by speakers of all languages, that
each name applies only to one species, and that each species has
only one name.
Bleeding
When sap or latex flows freely from a damaged stem.
Bloom
1. A flower. 2. A waxy white or bluish-white coating on stems,
succulent leaves or fleshy fruit.
Bract
A modified leaf at the base of a flower or flower cluster, which often
protects the flower. Bracts can resemble normal leaves, be small and
scale-like or large and brightly coloured and look like petals.
Bristle
A stiffened hair.
Cactophile
Person who likes cacti.
Caducous
Falling off early.
Caespitose
Offsetting to produce many stemmed cushions or mounds.
Calcareous
Of or containing lime or chalk.
Callus
The protective tissue formed over a wound, for example, at the base of
cuttings.
Calyx
The ring of sepals that surrounds the petals of a flower before it opens.
Cambium
Layer of tissue that gives rise to secondary growth in stems and roots
by cell division.
Campanulate
Bell-shaped.
Campylotropous
Said of an ovule curved back on itself so that the micropyle is near to
the hilum, as in Cactaceae.
Capsule
A dry seed pod that splits open when ripe to release the seeds.
Carpel
Female reproductive structure of flower, usually comprising ovary,
style and stigma; carpels may be solitary or grouped or fused with
others, as in Cactaceae (see Gynoecium).
Caudex
The swollen water-storage tissue, usually composed of both root and
stem, of a succulent woody plant.
Caudiciform
1. Possessing a caudex. 2. With a swollen stem.
Central spines
Those arising from the centre of the areole.
Centrifugal
Tending outwards from the centre or axis.
Centripetal
Tending inwards to the centre or axis.
Cephalium
Modified flowering zone of some cactus stems, often marked by
copious development of hairs and/or bristles. A distinction is
sometimes made between the true "cephalium" of Melocactus, for
example, where vegetative growth ceases when the cephalium forms
and various kinds of "pseudocephalium," where vegetative growth can
continue.
Chalaza
Basal zone of ovule where nucellus and integuments join.
Chasmogamy
(Chasmogamus) Production of flowers which open in the normal way
to expose the reproductive organs. (The production of flowers which
do not open is called cleistogamy)
Chimera
(pl. chimaera) A plant that contains a mixture of tissues from two or
more genetically different cells or tissues in the same part of a plant.
These can be spontaneously mutated cells of the host organism or
cells from a different organism or species produced as a result of
organ transplant, grafting (Graft chimera), and artificial fusion of unlike
tissues or genetic engineering. The name chimera derives from the
Old French, from Latin "chimaera", from Greek "khimaira", which
means chimera, she-goat. From Indo-European Root "ghei-" Chimera
is a Greek mythological character a fire-breathing she-monster made
up of the front parts of a lion, the middle parts of a goat, and the tail of
a snake she is the daughter of Typhon.
Chlorophyll
The green pigment present in leaves or stems and used in
photosynthesis.
Chlorosis
A more or less distinct lack of chlorophyll leading to the plant having a
sickly yellow colour. Often a symptom of deficiency of a micro-nutrient
such as iron or boron.
Ciliate
Fringed with hairs.
Cladode
A flattened stem that looks like a leaf. Particularly seen in Opuntia
(pads).
Clavate
Club-shaped.
Cleistogamous
Is the condition of having perfect flowers which do not open and selfpollination occurs, flowers are fertile and produce a lot of seed. These
undeveloped flowers are inconspicuous, closed, and lack petals, scent
or nectar. They are always fertile while the more perfect flowers of the
same plant are usually nearly or completely sterile. Practically all
cleistogamous plants can also produce normal open (or
chasmogamous) flowers. Cleistogamy appears to be related to
environmental conditions: when the environment is harsh, plants are
more likely to produce cleistogamous flowers (For example Frailea
castanea)
Collenchyma
Living tissue providing support and with characteristic unevenly
thickened walls.
Connate
Fused or grown together.
Cordate
Heart-shaped.
Corking
Gradual ripening of stem from the base, to produce a bark-like texture.
Corolla
The collective name of the petals.
Corona
The centre of the flower surrounding the stamens and style, the crown.
Cortex
Layer of tissue between epidermis and vascular tissue, or external
layer of such as bark or rind (adj. Cortical).
Cotyledon
Embryonic leaf; first leaf or leaves of a seedling after germination.
Crenate
With notched edges.
Crest
Also called fasciation; a mutation that results when the growing point
of a plant forms a long line, rather than a single point. In botanical
terms it is usually signified by Cristate.
Cristate
Crest-shaped or crested.
Cross-pollination
See pollination.
Cultivar
Assemblage of plants originated or selected and propagated artificially.
Cultivar (Cv.)
(cultivar = cultivated variety) a form of a plant commercially or
scientifically important derived from cultivation.
Cultivar names are given when the mutation occurs due to human
influence. Examples: a mutation occurs in a greenhouse (or because
of human involvement such as breeding, applying mutagens,
propagation, or by cultural practices) The abreviation cv. is used to
signify that the mutation is a cultivar. cv. is placed after the specific
epithet and is not underlined or italicised.
Example: Astrophytum asterias cv. Onzuka or single quotes of cv.
Astrophytum asterias 'Onzuka'
How to write:
1. The cultivar name is written after cv. or within the single quotes ( '....'
).
2. Capitalize the cultivar name.
3. Never underline or italicise the cultivar name.
Example: Astrophytum asterias cv. Onzuka or Astrophytum asterias
'Onzuka' Where a species' variation is great or strongly different from
the normal and sufficiently mutated it is called a 'sport'.
Cupules
Cup-shaped structure.
Cuticle
Thin, waterproof layer that cover the epidermis.
Cutin
Waxy, water-repellent substance impregnating cell walls.
Cutting
A cut or detached section of a plant, either from a leaf or stem, or an
entire leaf that is used for propagation.
Cyathium
(plural Cyathia). Specialised inflorescence found in Euphorbia species,
where several male flowers are reduced to a single stamen and are
found alongside a sing-ovary female flower. The male and female
flowers together are presented with often colourful bracts and/or
glandular nectarines.
Cymose
In the form of a cyme, a type of inflorescence in which the relative
main axis is soon terminated with a flower and subsequent growth
occurs from one or several side branches.
Damping off
The speedy wilting and collapse of seedlings due to fungal attack on
the seeding stem at soil level.
Deciduous
Shed periodically, or annually
Decumbent
Lying or growing along the ground but turning upwards at or near the
apex.
Decurrent
Running downward.
Deflexed
Bent away, usually applied to the shape of a spine.
Dehiscent
Splitting or bursting open.
Deliquescent
Becoming liquid.
Deltoid
Shaped like the Greek letter D (Delta).
Dentate
Toothed.
Diaphragm
Membranous protrusion in floral tube of some cacti which more or less
closes the nectar chamber.
Dichotomous
Forking equally; as when the stem divides into two equal branches.
Dieback
The progressive death of a stem from the tip due to damage or
disease.
Dimorphic
Having two forms (opp. Monomorphic).
Dioecious
Species that have male and female plants, i.e. the flowers on a
particular plant will have only male or female organs and plant of the
opposite sex is required in order to produce seed.
Distichous
Arrangements of branches or leaves in two opposite rows. (For
example: Haworthia truncata).
Diurnal
Day flowering.
Division
A method of propagation in which a single plant or a clump is divided
into several sections, each with its own roots and a growing point.
Dormancy
A temporary cessation of a plant's active growth and a slowing-down
of its other functions, usually in winter, in drought or in extreme heat or
cold. Some succulents can produce flowers when otherwise dormant.
Druse
Mass of needle-like crystals contained in a cell.
Endemic
Regularly or only found in a certain region or country.
Endosperm
Nutritive tissue formed within the embryo sac.
Entire
Smooth margins or edges.
Ephemeral
Short lived.
Epicotyl
Portion of the stem of an embryo plant or seedling lying above the
cotyledons (see Hypocotyl).
Epicuticular
"On the . . . Cuticle", especially epicuticular wax, a layer of wax
(continuous, powdery [farinose], or variously structured into plates,
coils etc.) cover the . . . Cuticle on the outer surface.
Epidermis
Outermost cell layer.
Epiphyte
Plant that grows on another plant without drawing nutrients from it (adj.
Epiphytic).
Ericaceous
Applied to acid compost with a pH of 6.5 or less. It is generally used
form lime-hating plants.
Etiolation
Pale, sickly, excessive growth caused by insufficient light, incorrect
feeding, or overcrowding.
Etymology
The etymology of a word refers to its origin and the historical roots of
the term as a linguistic form. Etymology, in general, is the study of the
origins and history of words. The roots of words.
The word etymology is derived from the Greek "etumos" which means
real or true. The ending "ology" suggests the study/science of
something, as in biology or geology. The Ancient Greek word "astron"
means "star". And "phyton" means "plant". Hence Astrophytum literally
means star plant. (See: Etymology of species names - Etymology of
genus and variety names)
Excrescence
Outgrowth, warty appendage, protuberance.
Exine
Outermost layer of the pollen grain (see Intine).
Exotic
Usually referring to tropical or sub-tropical plants.
Exserted
Sticking out; said of stamens and/or style which extend beyond the
perianth.
f. (fa.) Form
(forma).
Taxonomic rank below variety, used for a taxon that differs only in a
single characteristic or in a group of closely interrelated characteristics.
Family
A group of related genera. For example the family of Cactaceae
contains about 140 genera.
Farinose
Having a mealy appearance.
Fasciated
Having abnormal growth with flattened and laterally expanded stems
or irregular stems; caused by abnormal divisions of the growing point.
Fascile
Bundle or cluster.
Fibrous root
A fine, densely branching root, which absorbs moisture and nutrients
from the soil.
Filament
Stalk of stamen supporting anther.
Fissure
The aperture between two otherwise united leaves.
Flat grafting
See grafting.
Floccose
Woolly, hairy
Flowerhead
A mass of tiny flowers, or florets, that looks like a single large flower.
Forcing
The technique of bringing a plant into growth or flower ahead of its
natural season, usually by providing it with extra warmth or controlling
the day length.
Form
Cultivated or naturally occurring variant of a species, denoting a group
of plants with several common characteristics.
forma
(abbreviated f.)
From the Latin word "forma" meaning "form, shape" it is an
infraspecific rank below variety, this is the smallest taxonomic
category, generally used for sporadic or minor variations occurring
among individuals of any population, mainly in horticultural
applications. (E.g. spine length, flower or fruit colour, or habit
response) The abbreviation f. is used to signify that the mutation is a
form. forma (f.) is placed after the specific epithet and is not underlined
or italicised. How to write the name of a botanical form:
1. The form name is written after (forma) f..
2. Do not capitalize the form name.
3. Underline or italicise the form name but not the form designation.
Example: Strombocactus disciformis f. cristata (Strombocactus
disciformis forma cristata)
Funicle
Stalk of the ovule attaching it to placenta.
Fusiform
Spindle-shaped; elongated and terete, gradually tapering at each end.
Genus
In the classification of living organisms the genus. (pl. genera) is a
grouping of similar, closely related and morphologically similar
Species. Similarly, genera are grouped into families, families into
orders, orders into classes, and classes into phyla or divisions.
How to write:
1. The genus name is written first.
2. The genus name is always underlined or italicised.
3. The first letter of the genus name is always capitalized.
Example: Mammillaria or Mammillaria
Geophyte
Herbaceous plant where the stem is wholly or partly below soil level,
permanently of for short periods, for example, Pediocactus species
that pull themselves into the soil outside the growing season to find
protection from the elements, or caudiciform plants with swollen
underground food-storage organs.
Glabrescent
Becoming glabrous.
Glabrous
Smooth, without hairs or excrescences.
Glaucous
Possessing a smooth, blue-white, blue-green or blue-grey bloom.
Globose, globular
Globe-shaped, spherical.
Glochids
Barbed spines or hairs, mostly small and brittle; often in tufts,
characteristic of the Opuntioideae.
Glutinous
Sticky, glue like.
Graft chimera
Graft chimaera (frequently called 'graft hybrids') are cellular hybrids
between representatives of two or more named genera. They are a
rare phenomenon arising exclusively in cultivation where two species,
frequently of two distinct genera, are grafted together. The mingling of
tissues belonging to the stock and scion through grafting in a
nonsexual manner. The chimaera come up as a branch or shoot from
the point of union which contains tissues of both species, resulting in
an arrangement of both species being expressed in the shoot. Such
shoots can be vegetatively propagated and cultivated. The formula for
the graft-chimaeral nature of such a plants uses a " + " sign against the
initial letter of the generic name and to connect the two "parent"
species (not the multiplication sign " X " this show that they are not
sexual hybrids). If intergeneric, graft-chimaeras can be given their own
genus name (which is a combination of the two constituent generic
names) preceded by a + sign. An example is: + Ortegopuntia
(Ortegocactus macdougalii + Opuntia compressa). Graft chimaeras
can be given cultivar names. The example above has been named
+Ortegopuntia cv. Percy, They cannot be given species names.
Grafting
A method of propagation in which an artificial union is made between
two different parts of two closely related plants, a scion from one is
grated on to a stock from another so that they grow into one plant.
Methods include flat grafting, split grafting and side grafting.
Growing-point
Group of cells capable of division at the tips of the growing shoots and
roots, which produce new tissue.
Gynoecium
The female organs of the flower, as a whole.
Habitat
The natural home of a plant.
Hardy
Able to withstand most climatic conditions all year without protection,
often qualified with a minimum temperature, for example, -15c (5f).
Head
A close-set group of flowers.
Herbaceous
A non-woody plant in which the top growth dies down to a rootstock at
the end of the growing season.
Hilum
Scar left on the seed where the funicle was attached.
Humus
Decomposed organic matter.
Hybrid
A plant produced by crossing two different species within a genus or
from two closely related genera (intergeneric hybrid).
Hybridization
The production either in nature or in cultivation of a hybrid by crosspollination (see pollination).
Hygrochastic
Moving of plants parts caused by absorbing water or drying out.
Hypathodium
Inflorescence consisting of a flattened disk-like or vessel-like structure
into which individual flowers are sunk; typical of the genus Dorstenia.
Hypocotyl
Portion of the seedling below the embryonic leaves or cotyledons (see
Epicotyl).
Hypodermis
Layer(s) of cells immediately under the epidermis.
Imbricate
Overlapping.
Indehisent
A fruit that remains closed at maturity.
Inferior
Said of the ovary when positioned below the insertion of perianth and
stamens.
Inflorescence
Flower cluster or clusters.
Insertion
Attachment, for example of stamens in a flower.
Integuments
Outer and inner coats of the ovule.
Intercalary
Inserted between already differentiated tissue regions.
Intergeneric hybrid
See hybrid.
Internode
That part of a stem which lies between two nodes.
Interstitial pits
Depressions between (rather than within) testa cells.
Intine
Inner layer of the pollen grain or spore (see Exine).
isodiametric
Having the same diameter in all directions.
Joint
A section of the stem.
Keel
V-shaped ridge on one side formed by channel on the other surface.
Lanceolate
Shaped like a lance.
Lateral
A shoot or branch coming out of the main stem.
Latex
The milky white sap that exudes or bleeds from damaged stems of
some succulents, for example, Euphorbia.
Leaf bract
See bract.
Leaf cutting
A cutting composed of a single leaf.
Loam
A medium soil with equal parts of sand, silt and clay, which is usually
well-structured, fertile and moisture retentive but also free draining.
Mamilla
Nipple-shaped tubercle or podarium with the areole at its tip.
Margin
Edge of plant organ, such as a leaf.
Median
Situated in the middle, lying in the axial plane.
Medulla
Soft internal tissue, pith of stem or root (adj. Medullary).
Medullary rays
Bands of parenchyma between pith and cortex.
Meristem
Growth tissue; groups of cells capable of repeated division to form
permanent tissue.
Micronutrients
The nutrients required in small amounts, e.g. boron, copper, iron,
magnesium manganese and zinc. Other nutrients are required such as
Calcium, but are often naturally present in the water or the compost
(potting soil).
Micropyle
Opening in the integument of the ovule through which the pollen tubes
enter.
Mitotic cell division
Type of cell division where the chromosome set duplicates prior to
division.
Monocarpic
Flowering at the end of the natural life span, when the plant dies after
the fruits have ripened, such as most species of Agave.
Monoecious
Plants with flowers that have only male or female organs, but where
both male and female flowers appear on the same plant.
Monomorphic
Having a single shape or form (opp. Dimorphic).
Monopodial
With single axis extending at the apex, producing successive lateral
structures beneath it.
Monotype
The only species within a genus.
Monstrose
An abnormal, irregular stem growth.
Mucilaginous
Slimy, or jelly-like.
Napiform
Shaped like a turnip: Large and round at the top, tapering and very
slender below. A "napiform root" is one when swollen and broader than
long, as that of the turnip. The word napiform comes from the Latin
word "napus" meaning "turnip", and the Latin word "forma" meaning
"form, shape"
Naturalised
Referring to plants thriving away from their natural habitat.
Nectary
(extrafloral nectaries)
Extra floral nectaries are glands, usually located (in Cactus) in the
tubercle-grooves or in the axils. These nectary-glands exude a viscous
juice ( nectar) with a high sugar- content and represent a sophisticated
strategy for ant attraction.
-The first hypothesis for why plants secrete extra floral nectar is that
the presence of pugnacious ants seems to reduce the vulnerability of
flower buds by herbivores insect, resulting in greater fruit production
and tissue survival. (Or by decreasing seed predation on plants.)
-The second hypothesis is that they distract ants from foraging at floral
nectaries, this might also serve as an adaptation to reduce ant
visitation to flowers.
-The third hypothesis is the nutrient enhancement. Ant colonies tend to
concentrate nutrients in the immediate vicinity of their nests -- through
storing food, discarding debris, and defecating - plant that bearing
extra floral nectar attract ant nests to their base.
-Moreover ants can play an important rule in distributing the seeds of
this plant. In humid conditions, the nectar exudation (if not completely
removed by ants) can cause the formation of mould which leads to
ugly black-colouring of the epidermis. To prevent this, spray off the
plant with water to remove the nectar. And provide very good
ventilation.
(For example Coryphantha echinoidea)
Node
Point on stem where a leaf or leaves arises.
Nomen Nudum
Abbreviated n.n. A title lacking valid description.
Nucellus
Central structure of ovule containing the embryo sac.
nutrients
The chemical elements necessary for proper plant growth. Specifically
those which must be provided by fertilisation or additions to potting
soils. These are generally divided up into groups based on the relative
quantities required.
Obconic
Inverted cone-shaped.
Obovoid
Inverted egg-shaped, narrower near point of attachment.
Obtuse
Blunt, or partially rounded.
Offset
Side-shoot, often easily detached for propagation; offsetting, sprouting.
Ontogenesis
Development of an individual through its various stages.
Orthostichy
Arrangements of nodes, areoles and so on in a vertical row (see
Spirostichy).
Ovary
The base of the female portion of a flower that develops into a fruit
once fertilisation has occurred.
Ovate
Broadly elliptic, egg shaped.
Ovoid
Egg-shaped, broader near point of attachment.
Ovule
Outgrowth of a seed plants ovary that develops into a seed after the
egg cell it contains is fertilised.
Pan
A shallow pot that is wider than it is deep, often used for potting
established cacti and succulents.
Panicle
Lax inflorescence or flower cluster.
Papilla
(pl. papillae)
A small elongated or nipple-shaped protuberance on an organ from
any plant surface. A rounded projection from a portion of an epidermal
cell.
Papillose
(Also: papillar; papillate; papillary) of a rough surface, covered with
many tiny projections (papillae).
Parastichy
Secondary spiral in phyllotaxis.
Parenchyma
Basic living cell tissue.
Pathogen
Any micro-organism which causes disease, especially bacteria, fungi
and viruses.
Pectinate
Comb-shaped
Pedicellate zone
Portion of flower beneath ovary.
Peduncle
Main stem of a whole inflorescence.
Pendent
Hanging
Perennial plant
A perennial plant or perennial (from the Latin "per" meaning "through",
and "annus" meaning "year") is a plant that lives for more than two
years. This term is usually applied to herbaceous non-woody plants
plants or small shrubs rather than large shrubs or trees, but used
strictly it also applies to the larger and longer-lived species. Perennials
usually produce one or more flower crop each year.
Pericarp
The pericarpel at the fruiting stage.
Pericarpel
That part of the floral axis surrounding the ovary.
Periclinal
Said of outer or tangential cell-walls (opp. Anticlinal).
Periderm
Secondary protective tissue with cork cells.
Perinath
Calyx (sepals) and corolla (petals), taken together, in Cactaceae, the
sepals and petals form a intergrading series, termed perianthsegments, "tepals" or "sepaloids" and "petaloids".
Perisperm
Nutritive tissue in the seed formed outside the embryo sac.
Petal
Each of the segments of a corolla, usually coloured to attract
pollinators.
Petaloid
Petal-like.
pH
The horticultural measure of the acidity or alkalinity of a soil or
compost; pH7 is neutral, below pH7 is acid and above pH7 is alkaline.
Most cacti prefer a slightly acid compost.
Photosynthesis
The production by a plant of compounds required for its growth,
promoted by light acting on the plant's chlorophyll. Also needed in the
process are water and carbon dioxide.
Phyllotaxis
Mode of arrangement of leaves in relation to axis.
Pinching out
The removal of the growing point of a plant or its stems to induce the
production of side shoots or more flower buds.
Pinnate
Compound leaf with two or more pairs of leaflets.
Pistil
Female organs of flower, usually consisting of stigma, style and ovary.
Placenta
Part(s) of ovary which bear ovules.
Placentation
Arrangement of ovules within the ovary.
Plantlet
A new young plant, which usually arises from the site of a wounded
stem or leaf or is naturally borne on the leaf margins, for example in
some Kalanchoe.
Plumose
Feathery, covered with fine hairs.
Podarium
Nodal swelling. Corresponding to the leaf-base.
Pollen tube
Tube formed by protrusion of Intine which penetrates style to convey
pollen for fertilisation.
Pollination
(also known as cross-pollination). The transfer of pollen from the
anther to the stigma on the same or a different flower by gravity, wind,
birds, bats or insects in nature, or by hand in cultivation.
Pollinium
Waxy mass of pollen as found in the family Asclepiadaceae (and in
orchids).
Polyhedral
Many-faceted.
Porrect
Sticking straight out forwards.
Primary root
The first root which develops as a continuation of the radicle.
Primordium
Rudimentary outgrowth consisting of tissue capable of giving rise to,
for example, a leaf.
Procumbent
Growing along the ground.
Proliferous
Bearing offsets; also said of flowers or fruits which produce further
flowers from receptacular areoles, thus sometimes forming strings of
fruits.
Propagator
A small case, usually heated with a removable top of plastic or glass. It
is used to provide a suitable moisture retentive atmosphere for raising
seedlings or rooting cuttings.
Prophyll
Rudimentary leaf or bracteole at base of leafy shoot.
Prostrate
Low growing.
Pruinose
Frosted appearance with white powdery coating.
Pseudanthium
Reduced inflorescence which as whole appears to be a single flower,
for example, the flower heads of the family Compositae or the cyathia
in species of Euphorbia.
Pseudocephalium
An apparent cephalium of wool and/or bristles (see Cephalium).
Pubescent
Covered with fine, minute hairs.
Pulp
Juice or flesh which fills cavity of fruit.
Pulverulent
Covered in powder.
Raceme
Inflorescence where the main flower stalk does not end in a truly
terminal flower and where the flowers start to open from the bottom to
the top of the stalk. May be branched or unbranched.
Radial spines
The spines arranged around the edge of the areole
Radicle
Embryonic root.
Ramifying
Branching.
Raphe
Strand or ridge of vascular tissue in ovule connecting base of nucellus
with the placenta.
Receptacle-tube
Elongate-tubular part of the floral axis situated above the ovary,
supporting the floral organs; sometimes taken to include the
pericarpel.
Recurved
Curved backwards.
Reflexed
Curved downwards.
Resting period
The period of dormancy in a plant.
Reticulate
Net-like or criss crossing.
Rhizome
Somewhat thickened, fleshy stem rooting at the nodes while
continuing to grow at the tip, producing new leaves.
Rib
A ridge on a cactus stem, usually vertical, that is formed from the skin.
Root ball
The root mass, together with its soil or compost, visible when a plant is
lifted from its bed or taken from its pot.
Root crown
The point at which the root and stem of a plant meet and the primary
vascular anatomy changes from that of a stem to that of a root.
Transition point between stem and root. It may be clearly or vaguely
apparent
Rootstock
1. A vigorous plant which provides the root system in grafting. Also
know as a stock.
2. A plant's root system.
Rosette
A group of leaves radiating from approximately the same point, often
borne at ground level at the base of a very short stem, or at the tip of
longer stems.
Rostrate
With a beak-like projection (noun: Rostrum).
Rosulate
Arranged in the form of a rosette.
Rotate
Wheel-shaped; said of a flower in which the petals or perianthsegments radiate horizontally, like the spokes of a wheel.
Rugose
Wrinkled.
S.p.n.
Species nova: newly discovered.
Saxicolous
Refers to plants growing on rocks.
Scales
Thin, leaf-like structures.
Scientific name
How to Write a Scientific Name
Scion
A shoot or bud of one species which is united to the stock of another
plant by grafting, for propagation.
Sepals
Leaf-like structures surrounding and protecting the petals of a flower.
Collective know as the calyx.
Serial
Said of buds that arise sequentially.
Serrate
Saw-edged.
Sessile
Stalkless.
Shrub
Plant usually branching from the base rather than with a single stem or
trunk and branching higher up (see Tree).
Side grafting
See grafting.
Simple
Solitary.
Sinuate
Wavy-edged.
Spathulate
Spatula shaped, I.e. tapering from a rounded apex into a gradually
narrowing stalk.
Species
In the classification of living organisms the species, is the fundamental
unit of classification, consists of populations of related individuals that
resemble one another, that are able to breed among themselves, but
are not able to breed with members of another species. Populations
within a species that show recognizable, inherited differences but are
capable of interbreeding freely are called subspecies, races, or
varieties. How to write specific Epithet:
1. The specific epithet is written second.
2. The specific epithet is always underlined or italicised.
3. The first letter of the specific epithet name is never capitalized.
Spination
Spine characteristics and distribution.
Spines
Sharp-pointed, hard or woody structures, derived, in cacti, from leaves.
Spirostichy
Arrangement of nodes, areoles and so forth in spiral rows (see
Orthostichy).
Split grafting
See grafting.
Ssp.
Sub-species; plants with similarities but differing in certain features.
Stamen
Pollen-bearing male organ of flower, consisting of anther and filament.
Staminode
A sterile, usually reduced stamen.
Standard
A tree-like cactus obtained by grafting a trailing or arching species, for
example Schlumbergera, ot to a tall or columnar species.
Stapeliad
Common name used for members of the Asclepiadaceae
Stem cutting
A cutting taken from a portion of stem.
Stem succulent
Plant with succulent stems, without proper foliage leaves (e.g.: cactus)
Stigma
Surface or structure at apex of style, receptive to pollen.
Stock
See rootstock.
Stolon
Sucker or runner; a prostrate basal branch, above or below ground,
which can root and produce new stems or plantlets.
Stoloniferous
Producing stolons.
Stoma
Minute pore in epidermis through which gaseous exchange occurs
(plural Stomata).
Striate
Marked with lines on the surface, sometimes with slight ridge or furrow.
Strophiole
Swollen excrescence or appendage of the hilum of a seed.
Style
Structure, usually slender, connecting ovary and stigma(s).
Sub-genus
A division of a genus.
Suborbicular
Almost disc shaped; flat, with a circular outline.
Subsp.
Subspecies. Taxonomic rank below species and above variety and
form. There is no absolute definition for the term, which in recent years
has been used as a synonym for and in preference to "variety."
Subtending
Said of a leaf in whose axil there is a bud, areole and son on.
Subulate
Awl-shaped, slende3r and tapering.
Succulence
Juiciness, fleshiness.
Succulent
Juicy, fleshy, water-retaining; succulent plants store water in specific
organs, for example, stem-succulents, leaf-succulents.
Superior
Said of the ovary when the perianth and stamens are inserted below it
on the receptacle.
Synonym
Title already known under a different name.
Tap root
The principal swollen, downward growing root of a plant.
Taxon
Taonomic group, e.g. genus.
Taxonomy
The principles and practice of classification.
Tendril
Slender modified branch or leaf that is sensitive to touch and coils to
help a plant climb or anchor itself.
Terete
Rod-like, rounded and smooth, often tapering.
Terminal
At the tip of a stem or branch, usually applied to a bud, rosette or
flower.
Tessellate
Patterned like a mosaic or pavement.
Testa
Seed coat.
Throat
Of a flower; the visible portion between limb and tube.
Top-dressing
An inert material such as stone or grit, usually decorative, that is
applied to the surface of the soil or compost around the plant to aid
drainage and to decrease soil erosion or moisture loss.
Transverse
Across; at right angles to the vertical.
Tree
Plant with usually single, distinct trunk between ground and first
branching.
Tribe
Group ranking between genus and subfamily.
Truncate
Ending abruptly as if cut off.
Tube
The tubular section of the flower above the ovary, bearing the petals,
etc.
Tuber
Swollen underground stem with storage capacity.
Tubercle
Small, rounded prominence (adj. Tuberculate).
Tuberous root
Swollen root with storage capacity.
Turbinate
Shaped like a top or an inverted cone.
Type
The principal example of a genus or species.
Umbilicus
Navel-like formation; depression (adj. Umbilicate).
Undulate
Having wavy edges.
Variegation
A naturally occurring or viral induced mutation, which appears as
stripes or whole sections of tissue that are without chlorophyll.
Variegated varieties are often prized for the attractiveness of the
markings caused by the mutation.
Variety
A plants variety is a divergence in growth from the usual or normal of
one or a few of the characteristics of the species, this different growth
is inheritable by succeeding direct generations. Variety names are
given when the mutation occurs in nature. The abbreviation var. is
used to signify that the mutation is a variety. var. is placed after the
specific epithet and is not underlined or italicised.
How to write:
1. The variety name is written after var.
2. Capitalize the first letter of the variety name only if it is a proper
noun.
3. Underline or italicise the variety name.
Example: Mammillaria lasciacantha var. egregia (Mammillaria
lasciacantha var.egregia)
Vascular bundle
Group of conducting channels and associated tissues.
Vernalization
A process of thermal induction in plants, in which growth and flowering
are promoted by exposure to low temperatures
Verrucose
Covered in wart-like excrescences.
Verticillate
Arranged in whorls.
Viable
Able to survive and develop.
viscid
Sticky, glutinous.
Wart
An irregular growth (see tubercle).
Whorl
Cluster of three or more parts such as leaves radiating from single
node.
Window
A layer of semi-transparent cells, containing calcium oxalate, at the tip
of a succulent leaf. The window protects the chlorophyll in the plant
body from being destroyed by strong sunlight by diffusing the light
before it reaches the chlorophyll, so enabling photosynthesis to take
place.
Wool
Dense covering of fine, soft hairs.
Xeric
Having very little moisture; tolerating or adapted to dry conditions
Xerophyte
Plant adapted to dry conditions.
Zygomorphic
Bilaterally symmetrical; divisible in symmetrical halves in one plane
only (see Actinomorphic).