In this article we will discuss about:- 1. Characters of Anacardiaceae 2. Distribution of Anacardiaceae 3. Economic Importance 4. Affinities 5. Important Type.
Characters of Anacardiaceae:
Leaves alternate, exstipulate, simple or pinnately compound; auxiliary panicle inflorescence; flower pentamerous, hermaphrodite, actinomorphic, stamens 10 inserted at the base of an annular disc (intrastaminal disc); Carpels 1-2, Ovary superior with one pendulous or ascending ovule; fruit a drupe.
A. Vegetative characters:
Habit:
Generally trees and shrubs and rarely woody vines containing resin passages with gum or acrid juice.
Root:
Tap, root, deep.
Stem:
Erect, woody, hard, with resinous bark.
Leaves:
Alternate, (opposite in Dobinea) simple (Mangifera) or pinnately compound (Rhus, Odina), exstipulate.
B. Floral characters:
Inflorescence:
A terminal or axillary panicle.
Flower:
Small, complete, usually actinomorphic rarely zygomorphic, pentamerous, hermaphrodite but often unisexual (Rhus, Pistacia, Odina) by reduction of androecium or gynoecium, a nectar secreting disc or gynophore present; hypogynous.
Calyx:
Usually 5 sepals, sometimes 3 to 7, free, or basally connate or semi-connate, imbricate.
Corolla:
Petals 5-3 or absent (Pistacia) polypetalous rarely connate, imbricate, sometimes fused with the receptacle to form a hypanthium.
Androecium:
Stamens ten in two whorls of 5 each all fertile (Buchanania), in Anacardium, 10-7 of which only one is functional and the rest are staminodes; filaments free, basally connate,
stamens arise from the base of on intrastaminal disc, this disc may sometimes be modified into a gynophore, anther bithecous, introrse.
Gynoecium:
Tricarpellary rarely pentacarpellary, syncarpous, unilocular, superior, one pendulous ovule; in Bauchanania – ovary pentacarpellary and pentalocular with only one ovule; styles 1-5, widely separated.
Fruit:
Usually drupe, mesocarp resinous, and fleshy in Mangifera, sometimes nut (Anacardium).
Seed:
Cotyledon thick with little or no endosperm and curved embryo.
Pollination:
Entomophilous.
Floral formula:
Distribution of Anacardiaceae:
The family is also called Mango or Cashew family. It includes 80 genera and over 600 species according to Jones and Liechsinger (1987). Chiefly tropical but occurs in S. Europe, temperate Asia and also America. Mangifera extends from India to Malaya and the Philippines.
Economic Importance of Anacardiaceae:
1. Food:
Many plants yield edible fruits such as Mangifera indica (mango), Anacardium occidentale (Cashew-nut), Buchanania lanzan (Chironji), Harpephyllum caffrum (Kaffir plum), Spondias pinnata (Hog plum), Pistacia vera (pistachio-nuts).
Pistacia lentiscus (mastic tree) yields a mastic resin used in chewing gums, alcoholic beverages etc.
2. Varnish:
Many species of Rhus and Semecarpus yield resins and varnishes.
3. Gum:
Lannea coromandelica bark provide gum.
Schinopsis lorentzii and bark of Lannea coromandelica are used in tanning industry.
4. Ink:
Insect galls on the branches and leaves of various species of Rhus, Pistacia are used in manufacture of ink.
Semecarpus anacardium (Dhobis-nut) fruits provide black ink used for dyeing textiles and marking cotton clothes.
5. Skin irritants:
Rhus toxicodendron, R. quercifolia etc. are skin irritants.
6. Ornamentals:
Continus coggyria, Rhus typhina and Spondias pinnata are ornamental plants.
Primitive characters:
1. Plants mostly trees and shrubs.
2. Leaves alternate and simple in most genera.
3. Flowers hypogynous, hermaphrodite and Actinomorphic.
4. Sepals and petals free.
5. Stamens free and bithecous.
Advance characters:
1. Leaves compound in some species.
2. Flowers small inconspicuous and arranged in distinct inflorescence.
3. Flowers unisexual in Rhus, Pistacia.
4. Petals absent in Pistacia.
5. Gynoecium monocarpellary in many genera Mangifera, Anacardium.
6. Fruit drupe or nut.
Affinities of Anacardiaceae:
Bentham & Hooker, Engler and Prantl, Cronquist, and several other taxonomists placed Anacardiaceae in the Sapindales, while Takhtajan (1969) and Thorne (1983) placed in under Rutales. Hallier regarded the family (Sub-Terebinthaceae) as being ancestral to the amentiferous families and being descended from the Rutaceae.
The Anacardiaceae is related to the Sapindaceae in so far as the general habit and floral structure are concentrated. However, the distinguishing features, comprise the presence of intrastaminal disc, usually unilocular ovary and drupaceous fruit.
The family is, however, related closely to Aceraceae, Hippocastanaceae, Sapindaceae, Meliaceae, Rutaceae and Burseraceae. The recent trend is to divide Anacardiaceae into 5 tribes viz. Anacardiaeae, Spondiadeae, Rhoeae, Semecarpeae and Dobineae (Hickey and King, 1988).
Common plants of the family:
1. Anacardium occidentale L; Cashew nut, “Kaju” a small tree extensively cultivated in Madras, Kerala, Mysore and Andhra Pradesh.
2. Mangifera indica L. Mango “Aam” “Amra” grown extensively in Uttar Pradesh, Madhya Pradesh, the Punjab, West Bengal, Maharashtra and Madras.
3. Buchanania lanzen streng. (B. latifolia Roxb); Cuddapah-almond, “Chironji”, occurs throughout the country except in the dry North-West.
4. Pistacia vera L; pistachio nut “Pista”, cultivated in N. India.
5. Rhus vernicifera DC (Toxicocendron vernicifera DC); varnish tree.
Division of the family and chief genera:
The Anacardiaceae is divided into five tribes:
Tribe (i). Dobineae:
Female flowers naked, Carpel 1. Example: Dobinea.
Tribe (ii). Mangifereae:
leaves simple and entire. Carpels 1-5. Example: Buchanania, Mangifera etc.
Tribe (iii). Rhoideae:
Carpels 4-5 ovary free from floral axis with a solitary ovule. Examples: Pistacia and Rhus.
Tribe (iv). Semecarpeae:
ovary adnate to and sunken in thalamus. Example: Semecarpous.
Tribe (v). Spondieae:
Leaves pinnately compound. Carpels 4-5, connate; ovules as many as carpels. Example: Spondias.
Important Type of Anacardiaceae:
Mangifera indica (The mango, “Aam” Fig. 50.1):
Habit:
A medium sized tree.
Root:
Tap root, deep, branched.
Stem:
Erect, branched, hard, woody with resinous bark.
Leaf:
Simple, alternate, exstipulate, smooth, entire, long ovate lanceolate, acute, thick, coriaceous.
Inflorescence:
Racemose (Panicle).
Flower:
Bracteate, hermaphrodite, complete, actinomorphic. cyclic, hypogynous small pentamerous, yellowish green.
Calyx:
Sepals five, polysepalous, pale-green, imbricate.
Corolla:
Petals five, polypetalous, white or creamish with yellowish hue at base, imbricate. A fleshy, five-lobed disc is present between stamens and petals.
Androecium:
Stamens five, usually only one fertile, rest-reduced and sterile, filament long, anthers dorsifixed becoming versatile.
Gynoecium:
Monocarpellary, unilocular, superior, ovule one, marginal placentation, style long terminal or slightly laternal with one flat fringed stigma, a prominent 5-6 lobed hypogynous disc present, lobe : either opposite or sometimes alternate to petals. Carpels slightly (oblique) tilted to one side.
Fruit:
A fleshy large drupe with luscious mesocarp, long fibres.
Floral formula:
