Tag Archives: angiosperm

Dicotylidonous Family: Apocynaceae

Systematic position Bentham and Hooker placed it in the sub-class Gamopetalae,the series Bicarpellate and Cohort Gentianales . According to Engler it belongs to the sub-class Metachlymadeae, the sub-order Gentianineae under the order Controtae.Hutchinson places it under the order Apocynales of the Phylum Lignosae. Distribution The family contains about 300 genera …

Read More »

Gymnosperm: Introduction, Characteristics & Classification

Gymnosperms are seed-producing plants that do not produce any covering surrounding the seed i.e. the seed remains naked. The word ‘Gymnosperm’ originates from Gk. ‘gymnos’ meaning ‘naked’ and Gk. ‘sperma’ meaning ‘seeds’. A Greek botanist named Theophrastus first used the term ‘Gymnosperm’ in 300 BC in his book ‘Enquiry into …

Read More »

Apomixis: A Subistitution for Sexual Reproduction

Apomixis maybe defined (Winkler, 1908, 1934) as the substitution for sexual reproduction (amphimixis) of an asexual process which does not involve any nuclear fusion. For the sake of convenience it may be subdivided into four classes. Non-recurrent apomixis Recurrent apomixis Adventive embryony Vegetative propagation Non-recurrent apomixis In the first, or …

Read More »