Apocynaceae, Boraginaceae and Convolvulaceae- Introduction

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Apocynaceae
(Dogbane family)

Nerium

Plants of this family are trees (Alstonia, Holarrhena), shrubs (Thevetica, Nerium), herbs (Catharanthus), woody twiners (Allamanda) or even succulent (Adenium); usually twining shrubs with milky sap in laticiferous vessels. A family of about 200 genera and 2000 species of mostly tropical and subtropical distribution, but a few species are also distributed in temperate regions. About 30 genera and over 60 species of Apocynaceae have been reported from India. 
Selected Indian genera are: 
    • Apocynum, 
    • Catharanthus, 
    • Nerium, 
    • Plumeria, 
    • Tabernaemontana, 
    • Thevetica, 
    • Rauvolfia and 
    • Vinca.

Economic Importance
The family is of importance for its several ornamentals and for drugs.

Ornamental plants:
    • Allamanda nerifolia (golden yellow flowers)
    • Alstonia scholaris (pink flowers)
    • Beaumontia grandiflora (large white flowers)
    • Carrisa carandas (white-pink flowers)
    • Catharanthus roseus syn. Vinca rosea sadabahar, rosy purple flowers)
    • Mandevilla taxa (pink flowers)
    • Nerium indicum syn. N. odorum (kaner, white-pinky flowers)
    • Plumeria (white, red, pink or purple flowers)
    • Tabernaemontana divaricata (chandni, white flowers)
    • Thevetia peruviana (peeli kaner, yellow flowers)
    • Vallaris solanacea (dudhi bel).
Plants of Medicinal Value:
    • Rauvolfia serpentina is used in the treatment of hypertension and mental disorders; drug is obtained from the dried roots; the alkaloid reserpine of the plant can lower the blood pressure and tranquilize mental patients suffering from schizophrenia,
    • Thevetica peruviana, seeds are used in rheumatism,
    • Vallaris solanacea latex is useful in toothache and inflated gums,
    • Holarrhena antidysentrica root and bark is used in curing dysentry,
    • Cerbera manghas latex is used as an emetic and purgative,
    • Strophanthus hispidus seeds yield the drug strophanthin and
    • Wrightia  tomentosa bark and roots  are used as an antidote for snake bite.
Rubber is obtained from the coagulated latex of several species of Carpodinus, Funtumia, Hancornia, Landolphia and Rhynchodia.

Poisonous plants of family belong to Acokanthera, Nerium, Strophanthus and Thevetica. If one leaf of Nerium oleander or Thevetica peruviana is ingested, it may be fatal to adult human. poisoned arrows are made from the bark extract of Acokanthaera abyssinica and seeds of several species of Strophanthus.

Fruits of Carissa carandas (Karonda) are edible and used in pickles.

An indigo like dye is obtained from the seeds of Wrigthia tinctoria.





Boraginaceae
(Borage family)



 Usually bristly or hispid, hairy, herbaceous (Heleotropium) plants with fleshy roots or rhizomes; sometimes shrubs (some species of Tournefortia), trees (Ehretia, Cordia) or lianas (some species of Cordia). Entomophilous- pollination is by insects who are attracted by the presence of nectar, colour of the flowers and floral aggregation on the upper part of the inflorescence branches. 
        A family of approximately 100 genera and over 2000 species, distributed in both tropical and temperate regions but mainly in Mediterranean region. About 37 genera and 150 species have been reported from India. 
Selected Indian genera are: 
    • Heleotropium, 
    • Cynoglossum, 
    • Trichodesma, 
    • Ehretia and 
    • Cordia.
Economic Importance

Except for some ornamental and medicinal value the Borage family is not of much economic importance.

Ornamental plants:
    • Anchusa (Alkanet)
    • Borago (Borage)
    • Cordia (Geiger tree)
    • Cynoglossum (Hound's-tongue)
    • Echium (Viper's bugloss)
    • Heliotropium (Heliotrope)
    • Mertensia (Blue bells)
    • Myosotis (Forget-me-not)
    • Omphalodes (creeping forget-me-not)
    • Pulmonaria (Lungwort)
    • Symphytum (comfrey)
Plants of medicinal value:
    • Cordia myxa bark and fruits are used in coughs,
    • Ehretia macrophylla leaves are used in cough and stomach trouble,
    • Heliotropium indicum leaf decoction is used in fever, and roots in cough,
    • Lithospermum officinale seeds are used in urinary bladder diseases and
    • Onosma bracteatum leaves and flowers are used as tonic and diuretic.
Edible plants of family:
    • Cordia dichotoma (lassora) of which the unripe fruits are used as vegetable
    • Cordia gharaf (gondhi) of which fruits are edible.
Ratanjot a red dye, is obtained from the roots of Onosma hispid.

Wood of various species of Ehretia is used in making match boxes. brush backs, tea boxes, and other similar articles.






Convolvulaceae
(Morning glory family)

Morning Glory

Plants of this family are annual or perennial herbs, shrubs or rarely trees (some species of Erycibe), often climbing (Ipomoea) with somewhat milky sap; some with tuberous roots (Ipomoea batata) or  stems, others with rhizomes; Cuscuta is the stem parasite, twining around the host and sending haustoria roots; some are xerophytic and thorny; others are aquatic (Ipomoea aquatica).
                    A family of about 55 genera and 1650 species, distributed in both tropical and temperate regions of the world. About 20 genera and over 150 species have been reported from India. 
Selected Indian genera are: 
    • Argyreia, 
    • Convolvulus (blindwood or wild morning glory), 
    • Cuscuta (dodder), 
    • Evolvulus and 
    • Ipomoea (morning glory).

Economic Importance
This family is important as a source of food, for drugs, for several ornamentals etc.

Plants used for edible purposes:
    • Ipomoea batata (sweet potato), of which fleshy roots are eaten because of their rich content of sugar and starch and are also used for production of industrial alcohol, pectin, starch and sugar-syrup,
    • Ipomoea aquatica of which leaves and young shoots are used as vegetable,
    • Calonyction muricatum of which floral pedicels are eaten,
    • Calystegia sepium of which roots are cooked and eaten and
    • Rivea hypocrateriformis of which young shoots and leaves are used as vegetable.
Plants of medicinal value:
    • Evolvulus alsinoides is used as a bitter tonic,
    • Exogonium purga yields the drug 'jalap' used as purgative,
    • Ipomoea violate of which seeds contain d- lysergic acid amide and are hallucinogenic.

Plants of ornamental value:
    • Argyreia speciosa (elephant creeper)
    • Calonyction aculeatum (moon flower)
    • Ipomoea carica (railway creeper)
    • I. coccinea (star Ipomoea)
    • I. fistulosa
    • I. lobata
    • I. purpurea (morning glory)
    • I. quamoclit (Cyperns vine)
    • I. tuberosa (wood rose)
    • I. violacea (heavenly blue)
    • Porana paniculata (Christmas vine)
Plants used as sand binder:
    • Ipomoea biloba
    • I. fistulosa
    • I. pescaprae
    • I. fistulosa is also used as a hedge plant.
Plants which become troublesome weeds are Ipomoea arvensis and Cuscuta reflexa









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