Angiosperms Notes
Morphology of Flowering Plants
Angiosperms: All
flower-bearing plants are called angiosperms.
Characters:
1.
The angiosperms may be
annuals, biennials, or perennials.
2.
They may be herbs, shrubs, or trees.
3.
Xylem consists of
vessels, tracheid, xylem parenchyma, and fibers.
4.
They bare flowers for
reproduction.
5.
Archegonia are absent.
6.
Endosperms are formed by
triple fusion. Thus, it is a triploid structure.
(a)
Hydrophytes: Plants
that grow in water or inadequate supply of water are called hydrophytes. e.g.
Hydrilla, Nymphaea.
(b)
Mesophytes: Plants
that grow on land under the average conditions of water and temperature are called
mesophytes. E.g.: Mango tree, Mustard plant.
(c)
Xerophytes: plants
that grow in dry conditions or in scarce water are called xerophytes. E.g.:
Opuntia, Nerium.
The angiosperms are classified into two main groups,
i. Dicotyledons
ii. Monocotyledons
Differences between Dicots and monocots.
|
Dicots |
Monocots |
|
a.
Seeds contain two cotyledons. b.
They are often insect-pollinated. c.
The leaves show reticulate venation. d.
They usually contain tap root systems. e.
The leaves are dorsoventrally flattened. |
a.
Seeds contain one cotyledon. b.
They are Often water pollinated. c.
The leaves show parallel venation. d.
They usually contain adventitious root systems. e.
The leaves are isobilateral. |
Difference between Taproot and
adventitious root.
|
TapRoot |
Adventitious Root |
|
a.
It is usually underground. b.
It is the characteristic feature of the dicot plant. c.
The primary root continues to grow and gives off lateral branches. d.
It develops directly from the embryo and usually persists throughout
life. e.
It consists of a prominent main root that gives off many fine lateral
branches. |
a.
It may be underground or aerial. b.
It is the characteristic features of the monocot c. The primary root stops growing and it replaced many thin roots. d.
It develops from any part of the plant other than the embryo. e.
It consists of a cluster of roots that may be from the same point. |
Parts of Roots
The extreme part of a
root is called the root tip. It consists of a large number of cells. It is
called the zone of cell division.
Root hair is a part of a
plant that observed water and minerals. The main function of the root cap is to
protect the zone of cell division.
Shoot system
The system of a plant
which of the row above the soil surface, grows towards light phototropism or
negative geotropism is called shoot system.
Characters
-
Provides support to
various parts of a plant like a stem, leaf, bud, flower, fruit, etc.
-
Shoot is generally green
in color in the young stage.it consists of nodes and internodes.
-
Stem helps to transfer
water and minerals from roots to leaves. It transfers food prepared in leaves
to storage other growing parts.
-
Branches produce buds,
leaves, flowers, fruits.
There are two types of bud. They are:
i) Terminal bud
ii) Axillary bud
a. Vegetative bud
b. Floral bud
Flower:
It is the main reproduction
part of the plant. It has an asexual and sexual reproductive organ.
Asexual Reproduction:
1. Microspore: pollen grains (male
gametes)
2. Megaspores: ovule (ovum i.e. female gametes)
Modification of flowering plants
Modification of Roots:
The normal tap root is modified to store the good material. It changes its shape
and size due to the accumulation of food materials. This is called the modification
of root.
Modification of taproot:
it is the normal tap root modified to store the food materials. It changes its
shape and size due to the accumulation of good materials. According to their shape,
they are classified into following types.
-
Fasiform root
-
Napiform root
-
Conical root
-
Tuberous
Modification of adventitious root:
The adventitious roots
are modified to perform various functions such as the storage of food, support,
assimilation, and other important function.
1.
For storage of food:
a. Tuberous root
b. Annulate root
c. Nodulated root
d. Fasciculate root
2.
For mechanical support
a. Prop root
b. Stilt root
c. Climbing root
The stem
The stem is the aerial part of the vascular plant, developing
from the plumule and bears branches, leaves, and flowers. It is differentiated
into nodes and internodes which may not be distinct in some cases.
The habit of the plant:
The nature of the stem is
determined by the habitat of the plant. The plants are usually classified into
different categories according to their life cycle habitat or their life cycle.
Herbs: a small plant with the soft
or non-woody stem.e.g grass
Shrubs: a bushy perennial plant
with a woody or nonwoody stem. Branches arise from the base e.g China rose.
Tree: a tall woody plant with a woody stem. Branches develop well above the ground level. E.g mango tree,
peepal tree.
Annuals: plants that complete
their life cycle in one year. E.g. rice, maize.
Perennials: plants
that continue their growth for many years. Eg. Mango tree, apple tree, etc.
Modification of stem
1.
Underground modification:
there are always thick and fleshy having a good deposition of good material in
them. They are of the following types;
a.
Rhizome: it is a thick and fleshy
underground stem, which grows horizontally near the soil surface. It contains
dry scaly leaves at distinct nodes. It bears buds in axils of scaly leaves and
a terminal bud. The buds serve for vegetative propagation. E.g. ginger, fern,
mint etc.
b.
Tuber: swollen terminal portion
of an underground stem is called a tuber.it stores a large number of food
materials in the form of starch. The stem tuber bears a number of nodes called
eyes. Each eye bears a few buds.
c.
Corm: it is a short, vertical,
fleshy underground stem with a flattened base. It is more or less round and
bears several dry, thin scaly leaves. It has distinct nodes and internodes. The
corm stores a large amount of food material. It bears an apical bud, which
produces shoots with leaves and flowers. E.g. colocasia
d.
Bulb: it is a short
underground shoot with many scaly leaves. The food material Is stored in the
scaly leaves.
2. Sub-Aerial modification:
sub- aerial stems are found in plants with weak stems in which branches lie
horizontally on the ground. They are of the following types.
a. Runner: it is a long, slender, prostate stem
with long or short internodes. e.g. mint, grasses, oxalis etc.
b. Stolon:
it is a long, slender,
lateral branch that arises from the base of the stem.eg black jasmine etc.
c. Sucker: an obliquely upward growing branch arises from the underground part of the stem and root.
d. Offset: A horizontal, short, more or less
thickened stem. It originates from the axil of a leaf, extends for a short
distance and then produces a cluster of leaves above and adventitious roots
below. e.g. Pistia, water hyacinth etc.
3.
Aerial modification:
a. Phylloclade:
it is the characteristic
feature of some xerophytes plants. It is a short, green, flattened, or
cylindrical branch. It carries out photosynthesis and stores water for the
plant. It contains several nodes and internodes. The leaves are modified into
spines or scales to reduce evaporation. e.g. euphorbia
b. Stem
tendril: it is a thin, leafless
thread-like, spirally curved branch. It helps weak plat to climb. E.g. passionflower
c. Thorn:
stem modified into a
hard, often straight, pointed, and woody structure. It may bear leaves, flowers
in certain plants. The thorn arises in spring as axillary shoots with normal
leaves and with a special bud. E.g. lemon
d.
Twiner: long slender and branched
stem climbing by twisting its body around the support. Eg. Cuseuta
Climbers: A weak climbing
on support by means of special structure such as hooks, leaf tendrils, stems
tendrils etc.
The Leaf
They are the foliose part of
the plant. It is usually green in color and helps in the manufacture of goods,
transpiration, exchange of gases. The leaf is a flattened, lateral outgrowth of the
stem or the branch developing from a node. It is a photosynthesis appendage of
the plant, bearing chlorophyll. It manufactures food for the whole plant.
Structure of leaf:
i)
Leaf base: it is the basal part of the leaf by
means of which the leaf remains attached to the node of the stem. In some cases, leaf
base bears lateral outgrowths called stipules.
ii)
Petioles: It is a stalk below the lamina. It
helps in the attachment of the leaf. A leaf with petiole is called petiolate and
without is sessile.
iii)
Lamina: lamina is a flattened, expanded green
portion of the leaf. It possesses a number of thin veins. It is the most
important part of the leaf, which takes part in food production. It gives off
numerous thin lateral veins which branch further to form the veinlets.
Venation of leaf: The arrangement of veins and veinlets in the leaf is called
leaf venation. It is mainly classified into two types.
i)
Reticulate net-like
arrangement of veins is called reticulate venation. It is the characteristic feature of
dicot leaves. It is further classified into two types.
a.
Pinnate: single mid-rib
with lateral veins is called pinnate.
b.
Palmate: many midribs
with lateral veins arising from the petiole. It is also called multicostate
reticulate venation. E.g. hibiscus, cucumber etc.
ii)
Parallel venation: the arrangement of veins is more or less parallel to each
other is more or less parallel to each other. It is also classified into
pinnate and palmate types.
3. Shape of leaves: the shape of lamina varies greatly in different leaves.
(b) lanceolate: much longer than broad.
(c) Round: circular leaf lamina.
(d) ovate: broader base with narrow end.
(e) spathulate: spoon-shaped
4. Margins of the leaf:
(b) Palmate: margin divided in palm-like structure.
(c) Lobed: margin divided into many lobes. e.g. ranunculus.
5. Apex of the leaf:
(c) Acuminate: Apex ending in long, tapering pointed end. E.g. peepal
(d) Cuspidate: terminating in the appointment.
(e) Euspidate: apex ending in a long, rigid.
6. Leaf Surface: The leaf surface is of
various types and can be different according to the family. Some of them are
glabrous, hairy, spiny, rough etc.
7. Texture of the leaf: The textures of leaves are coriaceous, fleshy, succulent,
membranous, and scarious.
8. Phyllotaxy: Arrangement of the leaves
on the stem or in the branch is called phyllotaxy. They are of 3 types,
(A)
Alternate: if
the leaves are originated from each node and alternate from each other then
this kind of arrangement is called alternate arrangement. E.g. Mango
(B)
Opposite: if the leaves are
originated from each node and they are in an alternate position then this
condition is called opposite arrangement.
a. Superposed: if the leaves pairs at
upper and lower nods are exactly in same planes.
b. Decussate: if the pairs of leaves are
lies right angle to each other.
(C) Whorled: if more than two leaves are in the
same nodes then this condition is called whorled arrangement. E.g. Nerium
Types of leaves: on the basis of a number of leaf blades, they are of two
types. i.e. simple leaf and compound leaf.
a. Simple
leaf: Leaves having a single
leaf blade. The leaf lamina may be whole or incised into various lobes but the
incisions never touch the mid rib. E.g. Peepal
b.
Compound
Leaf: The blade is divided
into several segments called leaflets, e.g. rose
Types of Compound Leaf:
1.
Pinnately Compound leaf: The leaflets are borne on a central axis in two lateral
rows. They may be opposite or alternate. It is further classified into
(a)
Unipinnate: A pinnately compound
leaf with unbranched rachis. Leaflets arise directly on the rachis, e.g. Cassia
i) paripinnate ii)
imparipinnate
(c) Tripinnate: A pinnately compound leaf with secondary and tertiary branches leaflets arise on the tertiary rachis, e.g. Moringa.
(d) Decompound: Leaflets arise on the ultimate branches, e.g. Coriandrum.
2. Palmately compound leaf: Like the finger of a palm, the leaflets arise from a common
point.
(b) Bifoliate: leaf having two leaflets.
(c) Trifoliate: Leaf has three leaflets.
(d) Multifoliate: having more than four leaflets.
Inflorescence:
The arrangement of
flowers on the floral axis Is called an inflorescence. The main supporting stalk
of the inflorescence is called a peduncle and the supporting stalk of a single flower
is pedicel.
Classification of
Inflorescence: it is classified into
two types;
- Racemose or indefinite: The main grows continuously and develops on its lateral
sides in acropetal succession, i.e. youngest towards the apical end and oldest towards
the basal end. They are classified into the following type
a) Raceme b) spike c) spikelet d) catkin e)
Spadix f)umbel g) corymb h)compound Umbel i)
Head
- Cymose or Determinate: The main axis shows
limited growth. It is usually branched. The flower is borne in basipetal
succession, i.e. oldest towards the apical end and youngest towards the base.
|
Racemose |
Cymose |
|
1. the Main axis never terminates with floral buds. 2. Lower flowers are mature than the upper flowers. 3. Flower opening is centripetal. (outer mature and inner immature) 4. the Main axis continues to grow. e.g. Mustard plant |
1. the Main axis terminates into floral buds. 2. Upper flowers are mature than the lower flowers. 3. Flower opening is centrifugal. 4.
Main axis checked to grow. E.g. Jasmine. |
Flower
The flower is a modified
shoot of an angiosperm plant, especially for sexual reproduction. The flower
consist of an axis or receptacle, on which four types of floral leaves such as
sepals, petals, stamens, and carpels develop one after another. The flowers
develop from a bud known as a flower bud in the axil of a small leaf-like
structure called a bract.
The flower has a stalk
known as a pedicel, by which it is attached to the axis of a stem.
Fig: Flower showing parts
Some descriptive terms of flower:
Bract: a modified small leaf-like structure present at the base of flower.
Bracteole: a flower with a bract.
Ebracteate: having
no bract.
Bracteolate: flower
with bracteole, e.g. Adhatoda
Peadicellate: flower
with pedicel.
Sessile: having no stalk.
Sub-sessile: flower
with a short pedicel.
Involucre: a whorl of bracts.
Complete: having all four flora
whorls, i.e. calyx, corolla, androecium, gynoecium.
Incomplete: when any one of the four floral whorls is absent.
Actinomorphic or regular: a flower which can be divided into tow equal halves by
more than one longitudinal planes passing through the centre.
Zygomorphic: which
flower Can be divided longitudinally into two equal halves.
Irregular: when flower cannot be
divide into two equal parts by vertical plane.
Bisexual(hermaphrodite): flower with male and female reproductive organ in same
plant.
Unisexual: plant
with either male or female reproductive organ present.
Dimerous: flower with two or multiples of two
floral organs.
Trimorals: flower
with three or multiples of three floral organs.
Accessory organs: calyx and corolla are often referred to as accessory or
non-essential organs.
Essential organs: androecium and gynoecium, as they are directly involved in
reproduction.
Perigynous: A
cup-shaped structure around the gynoecium formed by the thalamus, gynoecium which
develops at the center of the cup and rest of the floral parts.
Epigynous: flower with inferior
ovary when further while other floral parts are inserted, i.e. superior e.g. cucrbita
Parts of a flower:
Accessory whorl
(a)
calyx
(b)
Corolla
Essential whorl
(b) Gynoecium
Calyx: it is the outermost whorl of the
flower. It is usually green in color and individual member of the calyx is
called sepal. The sepals may either remain green form each other or fused
together forming a bell shaped structure.
Caduceus: calyx fall down before
the flower opens perfectly. E.g. papaver somniferous.
Decidious: the sepals fall off
along with the petals at maturity after fertilization. E.g. Brassica
campestris.
Persistent: The sepals persist even
after the formation of fruit. It is of two types.
Accrecent: a persistent calyx
assuming a dried form. E.g. Guava
Corolla: The second whorl lying just inner to the calyx. It is composed
of a number of leaf-like brightly colored petals. All the petals may remain
either free from each other or fused together giving different shapes. Thus,
the petals help in pollination by attracting insects.
Like calyx, the free petals are known as polypetalous and fused petals are known
as gamopetalous.
Polypetalous corolla
ii Caryophyllaceous
iii Rosaceous
iv Papilionaceous
Gamopetalous corolla
ii Camepanulate
iii Infundibuliform (funnel shaped)
iv Rotate (wheel shaped)
v Ligulate (strap shaped)
vi Urceolate
vii Hypocrateriform
(A) Androecium(stamen)
Fig: Androecium
It is the male reproductive organ of the flower. It is made
up of one or more stamens. The stamens consist of
a.
Filament: it is the slender stalk
of the stamen, which bears the anther at its tip. There are four pollen sac that produces a large number of pollen grains or microspores. The pollen grains are
the male reproductive units.
b.
Anther: An anther with two loculus is called
dithecous, while in some cases the anther has only one locule and it is called
monothecous.
(B)
Gynoecium (pistil):
Fig: Gynoecium
The fourth innermost
whorl lying at the center of the thalamus is the female. It is composed of one
or more carpels. Each pistil consists of three parts. i.e. ovary, style, and
stigma.
The swollen basal part of
the pistils Is known as the ovary. The ovary may have one or more locules or
chambers. Each locule contains on or more ovules on placentae. The ovary gives
rise to the fruit and the ovules to the seeds. The slender stalk supporting the
stigma is called the style and the small rounded or lobed head of the pistil is
known as the stigma.
Note:
Placentation: the arrangement of placentae and ovules
on the ovary wall commonly known as placentation. They are marginal, axile,
parietal, central and free central, besal, superficial.
Fruit:
A ripened ovary enclosing
seeds is called fruit which is developing after fertilization. When only the
ovary of the flower develops into the fruit, is called true fruit. The
phenomenon in which the fruit develops without fertilization
is called parthenocarpy. A fruit mainly consists of two parts, i.e. pericarp and
seeds.
Pericarp: it develops
from the ovary wall.
Seeds: it develops from the ovule.
Types of fruit: They are of three types,
1.
Simple fruits: a
single fruit develops from the ovary of a flower with or without accessory parts.
They may be dry or fleshy, e.g. pyxis, poricidal.
2.
Aggregate fruits: simple fruits developing from an
apocarpous pistil of a flower are collected together to form an aggregate
fruit, e.g strawberry, rubus, etc.
3.
Multiple or composite
fruits: It develops from the entire
inflorescence, e.g. sorosis.
The seed:
The seed is a ripened
ovule developed after fertilization consist of an embryo and reserve food
surrounded by seed coat. The food may be stored in the cotyledons of embryo in
none endospermic or in a special tissue called endosperm.
Structure of dicotyledonous seed
The seed is covered by
two distinct layers of seed coats called testa and tegmen. Testa is the outer
coat that is smooth thick and maybe colored. The segment is an inner coat that is
thin membranous and hyaline which provides the necessary protection.
Inner to the seed coat is an embryo. Dicot embryo consists o0f a short axis with cotyledons. The cotyledons are
attached laterally to the embryonal axis. The portion of the axis lying outside
cotyledons and directed towards the mycropile.The cotyledon store of food
materials.
Fig: structure of Dicot seed
Structure of
monocotyledonous seed
A maize grain is a single
seeded fruit called caryopsis. The seed coat and wall of the food are fused
together to form a thin layer around the whole part. Coat surrounds endosperm
and embryo. The bigger one is the endosperm and the smaller is an embryo.
Fig: structure of monocot seed
Some Dicot and monocot Families:
Family: curciferae (Brassicaceae)
Distribution: the
family, includes 38 genera and 98 species, are found in Nepal. They are distributed worldwide and mainly grow in temprate and cold parts. Many species
are cultivated for vegetable, oil-yielding seeds and cosmetic production.
Habit: Most of the plants are annual, biennial, or perennial
herbs. A few species are small shrubs.
Root: Usually tap and branched, taproot may also become
modified like fusiform root or Napiform roots: These roots become swollen due
to the storage of food.
Stem: Commonly herbaceous,
erect, cylindrical, hairy, initially reduced but elongates after vegetative
growth and forms floral shoot. Stem is very much condensed.
Leaf: Radical, cauline, simple,
alternate, petiolate or sessile, exstipulate, hairy, Lyrate, unicostate,
reticulate venation. Floral characters: Inflorescence: Racemose, generally
raceme.
Flower: Ebractate, pedicellate,
complete, actinomorphic, rarely zygomorphic, bisexual, tetramerous, cruciform,
hypogynous.
Calyx: Sepals-4, polysepalous, arranged in two whole 2+2, imbricate
aestrivation, inferior.
Corolla: Petals- 4, polypetalous, cruciform, alternate with sepals,
aestrivation valvate or imbricate.
Androecium: Stamens-6, polyandrous, arrange in two whorls,
tetradynamous arrange in two whorls, tetradynamous is main characteristic of
the family. Another bilobed, basifixed and introres.
Gynoecium: Bicarpellary (2 carpels), the syncarpous, ovary is superior,
unilocular but becomes bilocular due to the development of a false septum,
parietal placentation, style short, stigma capitates.
Fruit: Siliqua or silicula.
Floral
formula: Ebr.
⃝ ○ K2+2 C4 A2+2 G(2)
Example:
1. Brassica campestris (tori)
2. Brassica oleracea (Kauli)
3. Brassica rapa (Gantemula)
4. Brassica nigra (Kali tori)
5. Raphanus sativus (mula)
Family: Papilionaceae
Distribution: it
includes more than 482 genera and 7200 species.
They commonly grow in subtropical and temperate regions. These families of many species are cultivated as important pulses and
vegetables.
Habitat: Most of the members of
this family are annual, biennial or perennial herbs or climbing, rarely they
are shrub and tree.
Root: branched taproot. The
roots are usually with nodules containing nitrogen-fixing bacteria like
Rhizobium spp. Due to this character, the plants are alsocultivated to maintain
soil fertility.
Stem: herbaceous or woody,
erect or weak climber, cylindrical, branched, solid, green and glabrous.
Leaf: alternate or whorled,
petiolate, stipulate with foliacious stipule, simple or compound, leaf lets are
modified into tendril in some species, reticulatevenation.
Floral characters:
Inflorescence: usually racemose types or solitary.
Flowers: bracteates, pedicellate, zyogomorphic, complete, bisexual,
usually pentamerous, hypogynous or perigynous.
Calyx: sepals-5, gamosepalopus, aestivation valvate or imbricate,
sometime bell shaped.
Corolla: petals-5, polypetalous, petals unequal, aestivation
imbricate, inferior.
Androecium: stamens 10, usually diadelphous (9+1), anther dithecous, basifixed
and introres, inferior.
Gynoecium: carpels 1 (monocarpellary) ovary superior, unilocular with
many ovules, placentation marginal, and style bent at base, flat and hairy,
stigma simple. Fruit: legume or pod.
Floral formula: Br. %O K (5) C1+2+ (2) A (9) +1 G1
Example:
1. Dalbergia sissoo (Sisau)
2. Pisum sativum (Pea)
3. Cajanus cajan (Rahar)
4. Glycine max (Bhatmas)
5. Vicia faba (Bakula simi)
Family: Solanaceae
Distribution: Most
of the species of the family are distributed in tropical and sub-tropical
region but some are found in temperate region. it is the largest genus
consisting 16 genera and 51 species are found in Nepal.
Habit: erect or climbing, herbs
or shrubs or rarely soft tree.
Root: Tap root.
Stem: erect, rarely climbing or
prostrate, herbaceous or woody, solid or fistular, hairy.
Leaf: cauline, alternate or
opposite, petiolate or sessile, exstipulate, entire, simple, rarely pinnately
divided, unicostate, reticulate venation.
Floral characters: Inflorescence: cymose.
Flower: ebracteate, pedicellate
or sub-sessile, complete, actinomorphic, hypogynous.
Calyx: sepals-5, gamosepalous,
campanulate sometime tubular, inferior, aestivation valvate or imbricate,
green.
Corolla: petals 5, gamopetalous,
campanulate, valvate or twisted aestivation. Androecium: stamens 5, free,
epipetalous, alternate to petals, anther basifixed, dithecous, introres and
inferior.
Gynoecium: bicarpellary,
syncarpous, ovary superior, bilocular, many ovules in each locule, axile
placentation with swollen placenta, style short, stigma bilobed. Fruit: berry
or capsule.
Floral formula: Ebr⃝○K(5) C(5) A5 G(2)
1. Solanum tuberosum Alu
2. Solanum melongela Bhenta
3. Lycopersicum esculentum Golvenda
Compositae ( Asteraceae)
Distribution:
It is largest family of angiosperms which includes about 1000 genera and about
23000 species, and cosmopolitan in distribution.
Habit: mostly annual or perennial herbs, some are under shrubs.
Root: tap or adventitious.
Stem: erect or prostrate, rarely climbing, herbaceous, woody,
solid and fistular. Leaf: radical or cauline, alternate or opposite or whorled,
commonly simple, rarely compounds, serrate or dendate, acute, unicostate
reticulate venation.
Floral characters: Inflorescence: head or capitulum, cyme.
Flowers: Two types of flower found in this family: - a. Disc florets
b. ray florets.
A. Disc florets Flowers: bracteate, sessile, actinomorphic, complete, bisexual,
pentamerous and epigynous.
Calyx: represented by 2-3 scales or by hairy or absent.
Corolla: petals 5, gamopetalous, tubular, valvate aestivation.
Androecium: stamens 5, epipetalous, filaments long, equal, anther
basifixed, dithecous, introrse and syngenesious.
Gynoecium: carpels 2, syncarpous, inferior, unilocular with single basal
ovules, placentation basal, style 1, stigma bifid.
Fruit: cypsela.
Floral formula: Br. ⃝ ○ K pappus or Scales or
absent C (5) A 5 G (2)
B. Ray florets
Flower: bracteate, sessile, zygomorphic, incomplete, unisexual,
epigynous.
Calyx: represented by 2-3 scales or by hairy pappul or absent.
Corolla: petals with 3-5 teeth, gamopetalous, ligulate valvate.
Androecium: absence. Gynoecium: carpels 2, syncarpous, ovary inferior,
unilocular with a basal ovule, placentation basal, style1, stigma bifid.
Fruit: cypsela
Floral formula: Br. %○K pappus or 2-3scales or absent C (3-5) A0 G (2)
Example:
1. Helianthus annuus suryamookhi
2. Tagetes patula sayapatri
3. Dahlia tuberose lahure phool
4. Artemisia vulgaris titepati
Liliaceae Family
Liliaceae is the family of around 2500 species of
perennial, herbaceous monocots. It is also known as the ‘lily family’. Its
characteristics are discussed below. Vegetative Characters
Root: Fibrous root system.
Stem: Erect; Liliaceae includes perennial herbs
which propagate through bulbs sor rhizomes.
Leaves: Alternate, simple; exstipulate; parallel
venation.
Floral characters
Inflorescence: Cymose- solitary; umbellate clusters.
Flower Perianth: Indistinctive: Complete, bisexual, actinomorphic; hypogynous,
perianth present (K, C).
sepal and petal;
six tepals (3+3), often united tepals; valvate aestivation.
Androecium: Six
stamens in two whorls (3+3).
Gynoecium: Syncarpous (Carpels united),
tricarpellary, trilocular, superior ovary with axile placentation (Carpel
towards ovule).
Fruit: Mostly Capsule and sometimes
berry.
Seed: Endospermic seeds.
