RUTACEAE
Systematic
Position :
Class :Dicotyledonae
Sub class :Polypetalae
Series : Disciflorae
Order :Geraniales
Family :Rutaceae
Distribution :
Rutaceae
comprises 150 genera and 1500 - 1600 species. The plants are widely distributed
in both tropical and temperate regions. The members are abundant in South
Africa and Australia. In India, the family is represented by 23 genera and over
80 species, predominantly in the tropical and sub tropical Himalayas and the
western Peninsular India.
Familiar Plants :
1.
Aegle marmelos Bilva or maredu
2.
Atlantia monophylla Karunimma.
3.
Citrus aurantium (Bitter Orange) Narinja.
4.
C. aurantifolia (Sweet lime) Nimma.
5.
C. limon (Lemon) Dabba.
6.
C. medica (Citron, Nimbu) Madiphalamu
7.
C. sinensis (Sweet Orange) Battai.
8.
C. reticulata (Loose skinned orange, Santra) Kamala Phalam.
9.
C decumara (= C. grandis) Shaddock, Pomelo, Pampara Panasa
10 Feronia elephantum (= Limonia acidissima,
Wood apple) Velaga.
11.
Murraya koenigii (Curry leaf) Karivepaku.
12.
M. paniculata (=M. exotica, Orange jasmine). Pooveiaga
13.
Naringi crenulata(= Limonia crenulata) Torra velaga.
14.
Ruta graveolens (common rue) Sadapaku
15.
Toddalia asiatica (Wild Orange Tree).
16.
Chloroxylon swietania (Satin wood) Billukarra.
Habit :
The
members are mostly shrubs or small trees, cultivated for their fruits. Herbs
are rare (Ruta).
Aegle
marmelos and Feronia elephantum are large sized trees.
Murraya
exotica is an ornamental shrub with scented flowers. The leaves and bark of the
trees are often fragrant due to the presence of oil glands.
Vegetative Characters:
1. Root System : Tap root system, often
infected mycorrhizae.
2. Stem : Usually erect, woody,
branched, armed with spires or unarmed (Murraya, Evodia). Young shoots are
gland dotted.
3. Leaf : Alternate, less frequently
opposite (Toddalia), simple, more often pinnately compound as in Murrava. In
Citrus sp. leaves are unifoliate with a joint at the junction of leaf blade and
winged petiole. In Aegle the leaves are trifoliate. Leaves are typically gland
dotted. In many genera, the first leaf of axillary bud modifies into spine.
Floral Characters:
1. Inflorescence
: Flowers are
clustered into axillary (Citrus Murraya) or in terminal cymes (Clausena,
Skimmia) or panicles( Murraya exotica). In some species of Citrus and
Triphasia, flowers are axillary and solitary.
2. Flower : Bracteate, bracteolate,
pedicellate or sub sessile, complete, bisexual, actinomorphic, hypogynous and
pentamerous. A distinct nectar secreting disc is present at the base of the
ovary. Flowers are rarely unisexual as in Toddalia, Evodia etc. or may be
polygamous as in Feronia. In Ruta, the lateral flowers are tetramerous, while the
terminal one is pentamerous.
3. Calyx : Sepals usually five and
polysepalous, green in colour and gland dotted. Sometimes 4 or 3 sepals are
also found. In zygomorphic flowers, the calyx becomes either tubular or cup
shaped. The aestivation is either imbricate or valvate.
4. Corolla : Petals normally five in
number, but may be four or three in some members. Petals polypetalous, but
gamopetalous condition is seen in Correya (Australia) and Galipea. (America)
Aestivation is valvate or imbricate, petals gland dotted and sweet smelling,
variously coloured.
5. Androecium : There is great variation in
the number of stamens. They may be as many as the number of petals, or twice
the number of petals. Stamens 8 - 10, arranged in two whorls. The outer whorl
lie opposite to petals and the inner whorl alternates with the outer whorl.
This arrangement is known as Obdiplostemonous.
Stamens
are some times numberous. In Aegle marmelos upto 60 stamens are present. In
Murraya 10 stamens are Present in 5+5 arrangement; stamens are 5 arranged one
whorl in the male flowers of Toddalia and Evodia. The anthers are dithecous,
basifixed and introse. The connective is usually glandular at the apex.
6. Gynoecium : Ovary superior, manocarpellary
(Empleurum), bicarpellary (Murraya) , tricarpellary (Triphasia) ,
pentacarpellary (Citrus spp.) and syncarpous. Ovary bilocular to Multilocular,
or unilocular as in Feronia. Placentation is usually axile, rarely parietal
(Feronia), Ovules anatropous. Styles as many as carpels, free or variously united.
Stigma terminal, entire or lobed.
7. Fruit : Usually a fleshy berry and is
called Hesperidium in Citrus spp. In Aegle marmelos and Feronia the berry is
large with a hard epicarp. In Acronychia the fruit is a capsule.
8. Seed : Seeds are generally endospermic,
with a straight or curved embryo. Polyembryony is a very common feature of
Rutaceae.
9. Pollination : Usually entomophilous. The
coloured petals, strong scent, nectar are the sources of attraction for the
insects. Cross pollination is favoured by marked protandrous condition of
flowers.
Floral formula :
Economic Importance :
The
family is of great economic value.
1. Edible fruits
: The most
important genus of the family, citrus provides various edible fruits like
oranges, limes and lemons. They have medicinal value.
(i)
Citrus aurantifolia - lime
(ii)
C. aurantium - Sour Orange
iii)
C. sinensis - Sweet Orange or mausambi
iv)
C. limon - lemon.
(v)
Aegle marmelos - Wood apple.
vi)
Feronia elephantum - Elephant apple.
2. Volatile Oils
:
(i)
Ruta graveolens : 'oil of rue'- is distilled from leaves and young shoots and
is used in perfumery and flavourings.
(ii)
Boronia megastigma : 'oil of Boronia' is, distilled from shoots, used in
perfumery.
(iii)
Amyris balsamifera: Source of a scented oil called West Indian Sandalwood oil.
(iv)
Amyris plumieri : ‘Mexican elemi’, an oleoresin is obtained from the bark,
Which is used in lacquers.
3. Ornamental
Plants :
1.
Murraya exotica (Marua)
2.
Ruta graveolens (Garden rue)
3.
Calodendrum
4.
Dictamnus albus
5.
Xanthophylum.
6.
Toddalia.
7.
Atlantia.
4. Other Uses :
1.
The leaves of Murraya koenigii are aromatic and are used in flavouring curries.
2.
The wood of Chloroxylon swietenia is known as Indian Satin wood and used in
making furniture.
3.
Timber from Flindersia brayleana is an important hard wood from Australia.
4.
Cusparia febrifuga gives 'cusparia bark' which is used as a substitute for
quinone.
5.
The twigs of Glycosmis pentaphylla and Zanthoxylum alatum are used as
chewsticks or tooth brushes in Indochina and Malayasia.
6.
The roots of Toddalia asiaticar a spiny shrub, are the source of a yellow dye.
The family Rutaceae is closely related
to Meliaceae Sapindaceae and Anacardiaceae in their external and anatomical
features. (heath – like habit, leaf structure, disc formation an
obdiplostamonous stamens). Some botanists relate Rutaceae to Euphorbiaceae on
account of the ventral raphe in ovule (in some
genera).
