Apocynaceae family

Plant classification system

1. DEPARTMENT OF LIFE SCIENCES SRINIVAS S. SURYAVANSHI M.Sc 2 nd plant sciences Roll no. – 2019MLS10

2. Gentianales Gentianales  is an  order  of  flowering plants , included within the   asterid   clade of  eudicots . It comprises more than 16,000 species in about 1,138 genera in 5 families. More than 80% of the species in this order belong to the family  Rubiaceae . Gentiana cruciata Scientific classification Kingdom: Plantae Clade : Tracheophytes Clade : Angiosperms Clade : Eudicots Clade : Asterids Clade : Lamiids Order: Gentianales Juss .  ex  Bercht .  &  J.Presl Families Apocynaceae Gelsemiaceae Gentianaceae Loganiaceae Rubiaceae Family  Apocynaceae  (424 genera) Family   Gelsemiaceae   (2 genera) Family  Gentianaceae  (87 genera) Family   Loganiaceae   (13 genera) Family  Rubiaceae  (611 genera ) Gentianales

3. Apocynaceae (Dogbane family ) ( Milkweed ) Greek for away From dog – in reference to some taxa used as dog poison. Belongs to order Gentianales includes 400 genera , 4,555 species. It has 5 subfamilies Apocynoideae Asclepiadoideae Periplocoideae Rauvolfioideae Secamonoideae Catharanthus roseus Rauvolfia Calotropis gigantea

4. Distribution Distribution Cosmopolitant native to European, Asian, African, Australian, and American tropics and subtropics In Indian 30 genera and 84 Species.

5. Vegetative characters Habit: Herbs, shrubs, twiners , lianas, with latex. tall  evergreen   trees   up to 80 m, with buttress roots, such as  Alstonia  and  Dyera   lianas , such as  Landolphia Asclepias syriaca ( common milkweed ,  butterfly flower ) Apocynum commonly known as  dogbane  or   Indian hemp. Many plants important for medicinal use, some plants are poisonous ,consisting of alkaloid , cardenolides , triterpenoids , and iridoids Apocynum androsaemifolium Asclepias syriaca Landolphia   Alstonia  

6. Roots Tap roots and branched Nerium oleander Stem Aerial , erect, herbaceous, woody / climber , latex in some thorny. Apocynum   cannabinum Alyxia oliviformi

7. Leaves Simple ,   usually opposite decussate rarely alternate whorled ,, Exstipulate , unicostate reticulate venation Alsts , Apocynum andresaemifolium Alstonia scholaris , Nerium oleander

8. Floral characters Inflorescence : Usually Cymose either Terminal or axillary May be corymbose cymes c yme ( Carissa ) or Umbellate Cyme Rauvolfia , cymose type   Calotropis gigantea Carissa Rauvolfia Calotropis gigantea

9. Flower : Bracteate or Ebracteate , Pedicellate, complete, hermaphrodite, Actinomorphic, Tetra or pentamerous, often with Corona Vinca minor Vinca roseus Allamanda cathartica Apocynaceae Oleander

10. Calyx : Sepals 5 , gamosepalous , polysepalous (vinca) rarely 4, deeply lobed small often Glandular at base ,quincuncial aestivation Corolla : petals 5 Gamopetalous , (oleander) funnel shaped twisted / valvate , but sometimes campanulate(Vinca) , carona like within tube (vinca and Oleander). Androecium :5 epipetalous , , alternating with petals , inserted and filament short , introse . Twisted Imbricate Apocynaceae Oleander

11. Gynoecium: 2 , bicarpellary , apocarpous, may be apically united , superior ovary usually bilocular with ovules or many ovules .axile / marginal placentation Fruits : A drupe (Thevetia), berry (Carissa), follicle ( Nerium / Calotropis) Thevetia Nerium Calotropis Apocynaceae Pollination : Entomophily , few ornithophily (Carissa),

12. Seed : Endospermic , hairy winged . Nerium oleander Plumeria Thevetia peruviana : dissection of toxic fruits

13. Floral diagram

14. Asclepiadaceae Vegetative characters : Habit: shrubs (Calotropis, Leptadenia), succulent (Stapelia) with latex. Root: branched tap root. Leaves : ,petiolate, exstipulate, entire, opposite rarely whorled, waxy; in Dischidia rafflesiana leaves are modified into pitchers , Floral characters: Inflorescence: Mostly umbellate cymes (Calotropis) Flower : Bracteate or ebracteate, pedicellate, complete, hermaphrodite, actinomorphic, pentamerous, hypogynous. Calyx: Sepals 5, polysepalous or gamosepalous-fused near the base, sometimes valvate Dischidia rafflesiana

15.   . Corolla: Petals 5, gamopetalous, 5 lobed, twisted aestivation or valvate , corona hairy out growth from petals i.e. staminal corona in Calotropi s . Androecium: Stamens 5 , synandrous, gynostegium (stamens fused with stigmatic disc to form gynostegium ), epipetalous; the pollen grains of each half anther usually agglutinated into granular mass of tetrads or waxy pollen called pollinium (Asclepias, Calotropis). Thus each stamen has two pollinia. . Gynoecium: Bicarpellary, syncarpous, ovaries free, superior, ovules many on marginal placentation, carpel is unilocular; stigmas united to form a pentangular disc with which anthers are fused to form gynostegium. Fruit: follicles. Seed: Many small, compressed with long silky hairs . Pollination: Entomophilous. Floral formula:                           

16. Economic importance of Apocynanceae : 1. Vegetables: fruits of Carissa carandus (H. Karaunda) are edible 2. Medicinal: The root of Rauwolfia serpentina (H. Sarpgandha) are used in lowering blood pressure, sedative, stimulator for uterine contraction and in mental diseases. The juice of leaves is used for removal of opacities of the cornea of the eyes. Anti-cancerous drugs are extracted from Catharanthus roseus. Holarrhena antidysentrica yields a drug which is a cure for amoebic dysentery. 3. Rubber: Many species of Hancora, Dyera, Urceola are the sources of rubber. 4. Poisonous: The seeds of Thevetia contain Thevetine a poisonous glycoside. The latex of Acokanthera is used for poisoning arrows. The bark and wood of Nerium indicum provide rat-poison. 5. Ornamental: Nerium, Catharanthus (syn. Vinca ), Thevetia, Wrightia , Allamanda are cultivated in gardens as ornamentals. Carissa carandus Rauwolfia serpentina

17. Holarrhena antidysentrica Thevetia Thevetia Allamanda

18. Stapelia gigantea )