In this article we will discuss about:- 1. Characters of Apiaceae 2. Distribution of Apiaceae 3. Economic Importance 4. Affinities 5. Important Type.
Characters of Apiaceae:
Stem fistular, leaves alternate, much dissected mostly decompound, sheathing leaf base; inflorescence umbel or compound umbel occasionally simple; flowers epigynous, pentamerous, regular rarely zygomorphic, hermaphrodite; calyx superior, pentafid or 0; corolla five, polypetalous, often inflexed; stamens 5; carpels 2; syncarpous, bicarpellary with 2 pendulous ovules; honey-disc surrounding the stigmas – stylopodium is present; fruit cremocarp; seeds endospermic and oily.
A. Vegetative characters:
Habit:
Plants are mostly herbs which may be annual, biennial or perennial, the herbs may be large (Bupleurum, Heracleum, Agelica) rarely shrubs with aromatic odour due to the presence of oil ducts. Pseudocarum climbs by means of its petioles which are very sensitive to contact.
Root:
Tap, branched sometimes swollen for the storage of food material e.g., Carrot (Daucus carota).
Stem:
Erect or prostrate; climbing in Pseudocarum; swollen nodes, sometimes ridged, usually fistular, glaucous or glabrous.
Leaf:
Cauline and ramal; radical in young plants of Daucus, usually exstipulate, stipulate in Centella; alternate, opposite in some species or Apiastrum; simple or much dissected, often decompound; petiolate, petiole usually sheathing at the base, venation reticulate unicostate (Centella), multicostate (Astrantia), parallel in Eryngium and Aciphylla. Palmately lobed leaves in Sanicula.
B. Floral characters:
Inflorescence:
Simple or compound umbel surrounded by thin leafy bracts called involucre; in some reduced to single flower e.g., in some species of Centella and Azorella; and to a compact head in Eryngium.
Flower:
Pedicellate, bracteate (Centella) or ebracteate (Foeniculum), perfect, complete, actinomorphic and in some zygomorphic due to the enlargement of the outer petals of the marginal flowers of the umbel (Coriandrum); hermaphrodite, pentamerous, epigynous, discus present.
In Echinophora each umbel has a central female flower surrounded by male flowers. In Arctopus and Aciphylla the flowers are fully dioecious. In Astrantia an intermediate condition is found.
Calyx:
Sepals 5, gamosepalous, small teeth or scales or absent (Foeniculum), adnate to the ovary, valvate, green.
Corolla:
Petals 5, polypetalous, epigynous often emarginate, tips inflexed, valvate (Foeniculum) imbricate, coloured.
Androecium:
Stamens 5, polyandrous, inserted under the disc, anthers dithecous, versatile, introrse, filament long, equal in length, bent in the bud but ultimately spreading out.
Gynoecium:
Bicarpellary, syncarpous, inferior, bilocular with a single pendulous bvule in each loculus, antero-posteriorly placed, axile placentation, style two; stigmas two; on the top of the ovary an epigynous glandular-stylopodium is present.
Fruit:
Schizocarpic cremocarp which splits into two one seeded mericarps, which rejnain attached to a slender often forked axis – the carpophore; mericarps are longitudinally ridged, in between the ridges are the farrows having oil ducts or vittae.
Seed:
Endospermic, embryo small.
Pollination:
Entomophilous due to nectar, scent and protandrous nature of flowers.
Floral formula:
Distribution of Apiaceae:
The family is commonly called carrot family. It was also named as Umbelliferae. It includes 295 genera and 2,850 species according to Willis. In India the family is represented by 180 species and 30 genera. The plants are distributed almost throughout the world except the arctic regions. The chief centres of the distribution are north temperate and sub-tropical regions.
Economic Importance of Apiaceae:
This family is of considerable importance from economic point of view chiefly because the plants have essential oil from which condiments or medicine are prepared.
Food:
Carrot (Daucus carota), celery (Apium graveolens), parsnip (Pastinaca sativa) and sowa (Peucedanum graveolens) are chiefly used as pot herbs.
Condiments:
Hing {Ferula foetida), Ajwain (Carum copticum), Zira (Cuminum cyminum), Saunf (Foeniculum vulgare), Dhania (Coriandrum sativum), are used as condiments or carminatives. Hing is a oleogum resin obtained from the roots. Ferula sumbul and F. galbaniflua also produce hing. Dorema also produces oleogum resin.
Fodder:
Several members as carrot, Heracleum, Angelica provide fodder for cattle and horses.
Medicinal:
Centella (H. Brahmi) is a very good tonic for brain. Hing, Saunf, Sowa, are used in digestive disorders. Peucedanum, graveolens (H. Sowa) is used as Dill water for children. Conium maculatum is the Hemlock plant. Its poison was given to Socrates; medicinally it is important in all spasmodic affections such as cholera, epilepsy, whooping cough, mania etc. Conium yields the alkaloid coniine.
Apium graveolens (H. Ajmud) produces apiin and used medicinally as cardiac tonic, or in asthma etc.
The fleshy roots of Cicuta and Aethusa are poisonous to all kinds of livestock.
Ornamental:
Trachymene, Angelica, Eryngium, Heracleum are cultivated in gardens for their beautiful flowers.
Primitive characters:
1. Plants are generally perennial and shrubby.
2. Leaves are simple and alternate in most of the genera.
3. Corolla is polypetalous.
4. Stamens polyandrous.
5. Flowers are actinomorphic and hermaphrodite, insect pollinated.
6. Seeds endospermic.
Advanced characters:
1. Plants mainly herbaceous-annuals or biennials.
2. Leaves finely dissected and compound or decompound in many genera.
3. Inflorescence umbel – simple or compound.
4. Flowers small and in some zygomorphic; epigynous.
5. Calyx gamosepalous in most of the genera.
6. Number of sepals and petals is fixed i.e. 5.
7. Stamens 5 with versatile anthers.
8. Carpels two and syncarpous.
9. One ovule in each loculus.
10. Reduction in the number of ovules i.e. two and the number is persistent in whole family.
11. Presence of stylopodium.
12. Fruit simple, cremocarp.
Since the advanced character out number the primitive characters, the family has been regarded as the most advanced family of the polypetalae.
It shows remarkable advanced tendencies viz.:
1. small size of flowers;
2. flowers arranged in umbel or compound umbel;
3. flowers epigynous;
4. number of sepals, petals are not more than 5 in any member;
5. carpels two, syncarpous, bilocular with 2 pendulous ovules;
6. characteristic cremocarp fruit of the family.
Affinities of Apiaceae:
The origin and taxonomic position of this family, Apiaceae reveals that the family is advanced in the scale of phylogeny and is the last of polypetalous Archichlamydeae.
Its taxonomic position just after Myrtales and preceding Sympetalae or Gamopetalae has been adopted by most of taxonomists. The origin is traced from Rosales as a result of epigyny from perigyny; reduction in number of carpels and ovules are also noteworthy.
The family Apiaceae also throws some light on the origin of sympetalous advanced families like Rubiaceae and Asteraceae (Compositae). This view is proved on the fact that in both Apiaceae and Rubiaceae there is tendency of flowers to be aggregated into umbellate heads, reduction of calyx lobes, epigyny, pendulous ovule, bicarpellary ovary.
Bessey supports this view and postulated that the Apiceae was directly derived from Rosaceae and the Umbelliferae in turn gave rise to Rubiaceae. Asteraceae is the last and most advanced family in the Dicotyledons.
The family is further advanced in having a honey secreting disc or the stylopodium and protandrous nature of flowers.
Common plants of the family:
1. Apium graveolens (H. Ajmud):
Cultivated and leaves used as vegetable salad.
2. Carum copticum (H. Zira):
Cultivated for its medicinal properties.
3. CoriancLrum sativum (H. Dhania):
Cultivated for leaves and fruits.
4. Centella asiatica (syn. Hydrocotyle asiatica) (H. Brahmi):
Wild along the river and canal side.
5. Daucus carota (Carrot; H. Gajar):
Cultivated for its edible roots.
6. Ferula foetida (H. Hing):
Inhabitant of Persia; also cultivated in hills for the milky juice of the roots.
7. Eryngium caeruleum:
Roots of this plant are nerve tonic.
8. Pimpinella anisum:
Cultivated in Punjab, Assam, U.P. and yields oil.
Division of the family and chief genera:
Engler classified the family into three sub-families on the basis of fruit characters:
Sub-family I. Hydrocotyloideae:
Stipules present, fruit with no free carpophore and woody endocarp; vittae none or in main ribs. Centella, Azorella.
Sub-family II. Saniculoideae:
Stipules absent, endocarp soft; style long with capitate stigmas, surrounded by ring-like disc, vittae various. Eryngium, Sanicula, Astrantia.
Sub-family III. Apioideae:
Stipules absent, endocarp, soft style on the apex of disc; vittae various. This sub-family is further sub-divided into 8 tribes. Coriandrum, Carum, Apium, Foeniculum, Daucus etc.
Important Type of Apiaceae:
Foeniculum vulgare (Fig. 66.2):
Habit:
Tall annual herb, cultivated for its condiment value.
Root:
Branched tap root.
Stem:
Herbaceous, aerial, cylindrical, fistular, glaucous, branched, angular, green.
Leaf:
Alternate, exstipulate, sheathing leaf base, petiolate, finely dissected-decompound, segments linear, entire, acute, glabrous, aromatic, unicostate reticulate ventation.
Inflorescence:
Compound umbel.
Flower:
Ebracteate, pedicellate, complete, hermaphrodite, actinomorphic, pentamerous, epigynous, yellow.
Calyx:
Sepals 5, gamosepalous, small or reduced, teeth like, valvate.
Corolla:
Petals 5, polypetalous, petals notched and inflexed valvate yellow.
Androecium:
Stamens 5, polyandrous, filaments long, anthers dorsifixed, dithecous, introrse.
Gynoecium:
Bicarpellary, syncarpous, bilocular, inferior, single pendulous ovule in each loculus, stylopodium present and prolonged into two short styles; stigmas two capitate.
Fruit:
Cremocarp, breaks up into 2 mericarps.
Seed:
Endospermic.
Floral formula: