Short Notes on Amaryllidaceae | Angiosperms

The below mentioned article provides short notes on Amaryllidaceae.

Salient Features of Amaryllidaceae:

Amaryllidaceae is a family of perennial herbs containing 59 genera and at least 800 species. The members are distributed mainly in tropical and subtropical areas of the world, Holarctic, Paleotropical, Neotropical, Cape and Australian.

Widely distributed in neotropics, from Mexico through Central America and the West Indies. Hippeastrum is found in Andes and Eastern Brazil, Hymenocallis in Mesoamerica, Clinanthus is endemic to Peru and Zephyranthes is world wide distributed.

Vegetative Characters of Amaryllidaceae:

Perennial, herbs with bulbous or rhiomatous stem. Sometimes shrubby or arborescent.

Bulbous habit:

Narcissus, Galanthus, Amaryllis, Crinum etc. where the plant body is truncate, bulbaceous, first leaves are amplexicaule, scape arises in the axil of upper leaf just below the terminal bud. New bulb is formed by the axillary bud in the axil of another axillary bud.

Rhizomatous habit:

In Alstroemaria rhizome is sympodial bearing a long leafy terminal aerial stem. Further growth of rhizome continues by a bud in the axil of a scaly leaf of the rhizome at the base of axillary shoot. In Hypoxis and Curculigo the rhizome is thick.

Arborescent habit:

In Agave, Fourcroya etc. the stem is short stubby or tall cylindrical. Leaves are thick or fleshy, lanceolate or linear with a spiny margin and apex. Leaves form dense rosette.

Terminal bud elongates to form thick woody scape bearing scattered dry scale leaves and ending in a massive inflorescence. Age of the plant at the time of flowering may be more than 5 years. Agave americana is also known as century plant and Fourcroya longaeva has a vegetative period of more than 400 years.

The massive scapose inflorescence ends the life of shoots. Scape may be 30-35′ high. Plants generally monocarpic Vellozia hemispherica appears to be dichotomously branched due to cease of growth of terminal bud; further growth continues by two axillary buds.

Leaves:

Mostly deciduous, alternate spiral (Crinum) or distichous, herbaceous, petiolate or sessile, sheathing, base simple, Lamina linear, lanceolate or oblong, ovate or orbicular, margins entire, parallel venation, leaves with persistent basal meristem and basipetal development.

The genera occupying low intensity habitat like Eucrosia have leaves which are broad and flat. The plants occupying semiarid regions like Gethyllis, Haemanthys etc. The leaves are covered with variously shaped hairs and in Crossyne, Haemanthus sp. leaves are spotted with dark green and red.

Floral Characters of Amaryllidaceae:

Inflorescence:

Flowers normally cymes, or umbel or head. Usually scapose, solitary terminal is Cooperia, Galanthus, Vellozia etc. single flower preceded by a spathe. In Galanthus spathe longitudinally splits on anterior side.

Umbellate clusters are present in Crinum, Narcissus etc. In Agave the inflorescence is mixed type while in Curculigo it is racemose i.e. a terminal spike. In Gethyllis the scape carries only one flower and remains subterranean.

Flower:

Bracteate, actitnomorphic or due to declination of Perianth medianly zygomorphic, e.g. Alstroemeria, Pedicellate, trimerous, bisexual, epigynous. The flowers are large and showy.

Perianth:

6 tepals, poly or gamophyllus in two whorls of 3+3 generally petaloid, shape of flower varies from star like to trumpet shaped or tubular end colours range from red, orange, pink, white or yellow. Bluish flowers are found only in Griffinia. Worsleya and Lycoris.

The flowers of Narcissus (deffodil) characteristically have a large cup shaped corona which is an outgrowth of tepals. Corona is found at the junction of perianth tube and the free lobes of tepals as a circular ridge of paracorollary structure. Sometimes it may be trumpet like.

Androecium:

6-stamens, epiphyllous inserted at the perianth throat or at the base of each tepal. In Griffinia sp. 5 stamens are present while in Gethyllis sp. the number may be 12-18 stamen attached in 6 clusters of 3 each at the throat of corolla. In Vellozia the number of stamens is more than six.

In Pancratium and Hymenocallis the stamen are fused to form a large staminal cup which resembles the corona of Narcissus. Stamens are 3 in Zephyra, diplostemenous, alternipetalous, filantherous (filaments appandaged alongside the anthers), or appendiculate (connate or expanded to form staminal corona as in Crinum) or non appendiculate, Anther dorsifixed or basifixed, versatile usually, introrse, rarely laterose (Crinum), anthers dithecous, splititing longitudinally, rarely by pores.

Gynoecium:

Tricarpellary, syncarpous, inferior, trilocular, axile placentation, unilocular, basal placentation (Calostemma) In Leontochir (monolytric Chilean genus) the ovary is unilocular, parietal placentation, style one, stigma trilobed. All the members produce nectar and are often heavily scented.

Fruit:

Capsule or fleshy berry containing dry, dark or flatterd, fleshy round and greerish seeds. Seeds endospermic with oily endosperm, phytomelanous testa and caruncular elaisome at the chalazal end.

Economic Importance of Amaryllidaceae:

Amaryllidaceae has greatest economic value as ornamentals. A large number of plants are traded for traditional medicines. Africans use the bulbs and leaves as poultices and decoctions for treating sores and digestive disorders, but in large dosage they are extremely poisonous.

i. The zulu people of S. Africa also use rhizomes of Clivias as protective charms.

ii. In Peru the Inca people frequently depicted flowers of Amaryllidacee e.g. Ismene, Pyolirion and Stenomesson etc. on ceremarial drinking vessels.

iii. In South Africa though indigenous and potraying plants are rare but the single known rock painting of a Brunsvigia species in Lesothor probably emphasizes how much the San people valued the bulbs for their Psychoactive effects.

Ornamental plants:

Agapanthus — African lily.

Agave americana —Century plant

Polianthes tuberosa — Tuber rose

Gallanthus nivalis — Snow drop

Crinum asiaticum — Sukhdarshan

Narcissus pseudconarcissus — Daffodil

Amaryllis vittate:

Amaryllis belladonna — Belladonna lily

Zephyranthes grandiflora — Zephyr lily.

Leucojum — Snow flakes.

Fiber plants: Fiber is obtained from leaves.

Fourcroya foetida — Mauritus hemp

Agava americana — Century plant.

Edible:

Curculigo lattifolia — Fruits edible.

Alstroemeria — Roots edible

Sytematics and classification:

Hutchinson included those taxa with cymose umbellate inflorescence only in the family. Subfamily Amaryllidoideae and Agapanthaceae, Allieae and Gilliesieae, Agavoideae is raised to family Agavaceae adding Yuccaceae, Nolineae and Dracaeneae of Liliaceae.

There are differing views as to the limits of the family, on the narrowest view it consists of 60 genera with 800 species. The members are called Amaryllids’ which can be recognized by their rather fleshy and two ranked leaves and their large and showy flowers, with an inferior ovary and six stamens, arranged in umbels at the apex of leafless flowering, scape.

The Amaryllidaceae does not include somewhat similar looking members of onion family the Alliaceae, which differs in having a superior ovary and presence of allyl sulphide compounds giving them special smell or arona nor another close relative Agapanthus family Agapanthaceae, which differs also is the position of ovary and lack of steroidal Saponins.

The most recent APG classification takes a broader view of the Amaryllidaceae which is subdivided into 3 subfamilies:

1. Amaryllidoideae (Old Amaryllidaceae family),

2. Allioideae (Old Alliaceae family), and

3. Agapanthoideae (Old Agapanthaceae family).

The family was first described by French naturalist Jean Henri Jaume Sain Hilaire in 1805 who named the family after Amaryllis. Amaryllidacea is recognized with varying definitions by most of the taxonomists of 20^th Century. Cronquist included it with a broadly defined Liliaceae. The two families have traditionally been separated by including species with inferior ovary in Amaryllidaceae and with superior ovary in Liliaceae.

APG initially in 1998 recognized the Agapanthaceae, Alliaceae and Amryllidaceae as separate family. In 2003 rivision advocated the three families as three subtaxa of a single familiy Asparagales. Recent mission of 2009 suggests that three families should be combined as separate subfamilies of a broadly defined Amaryllidaceae.

Despite these proposals to combine the three families in Amaryllidaceae Senu lato their differences regarding chemical compounds and morphology are nevertheless considered sufficiently important by some authors to keep them apart.

Amaryllidaceae are one of the few families of the higher Asparagals well defined by other than molecular characters, viz. combination of umbellate cymes, inferior ovaries and unique alkaloid chemistry.

The Amaryllidaceae has so far defied precise understanding of its intrafamilial phylogeny, and its relationships to other families of higher Asperagales. Combined analysis of three plastid DNA sequences (rbcL, trnL intron and trn L-F spacer) for 50 genera of Amaryllidaceae analyzed together with members of Alliaceae, Behniaceae, Convallariaceae, Hyacinthaceae, Themidaceae and Hemerocallidaceae resolve Agapanthaceae as sister to Amaryllidaceae with weak support and places Agapanthus -Amaryllidaceae as a sister clade to a monophyletic alliaceae.

Kingdom: Plantae

Unranked: Angiosperm

Unranked: Monocots

Order: Asparagals

Family: Amaryllidaceae.

Habitat loss is currently the greatest threat to the Amaryllidaceae in South Africa where 59 species are endangered or vulnerable and 58 species are near threatened.