Reproduction of lower & higher plants

01 Reproduction in Lower and Higher Plants - part 01 - Asexual Reproduction


 Reproduction :

  • It  is the production of young ones like parents. 
  • Essential process as it leads to continuation of species as well as to maintain the continuity of life. 
  • Each organism has its own particular method of reproduction. 
  • All these methods generally fall into two categories : 
  1. Asexual reproduction 
  2. Sexual reproduction.


1. Asexual Reproduction : 

  • Asexual reproduction does not involve fusion of two compatible gametes or sex cells. 
  • It is the process resulting in the production of genetically identicalprogeny from a single organism and inherits the genes of the parent. 
  • Such morphologically and genetically identical individuals are called clones. 
  • Organisms choose to reproduce asexually by different modes or ways: 
A. Fragmentation : 


  • Multicellular organisms can break into fragments due to one or the other reasons. 
  • e.g. Spirogyra. 
  • These fragments grow into new individuals.

B. Budding : 

  • It is the most common method of asexual reproduction inunicellular Yeast. 
  • Usually it takes place during favourable conditions by producing one or more outgrowths (buds). 
  • These buds on seperation develop into new individual. 
C. Spore formation : 


  • In Chlamydomonas asexual reproduction occurs by flagellated, motile zoospores which can grow independently into new individuals.


  • Other methods of asexual reproduction include - 
  1. Binary fission which occurs in Amoeba, Paramoecium.
  2. Conidia formation in Penicillium and 
  3. Gemmules formation in Sponges.


Vegetative Reproduction : 

  • Plants reproduce asexually through their vegetative parts. Hence, the new plants formed are genetically identical to their parents.  
  • There are also few methods which would not occur naturally in the plants. 
  • Agriculture and horticulture exploit vegetative reproduction in order to multiply fresh stocks of plants. 
  • Artificial methods are used to propagate desired varieties according to human requirements. 
  • The various methods are as follows : 
a. Cutting : 

  • The small piece of any vegetative part of a plant having one or more buds is used for propagation viz. 
  • Stem cutting - e.g. Rose, Bougainvillea; 
  • leaf cutting - e.g. Sansvieria; 
  • root cutting e.g. Blackberry. 
b. Grafting : 


  • Here parts of two plants are joined in such a way that they grow as one plant. 
  • In this method, part of the stem containing more than one bud (Scion) is joined onto a rooted plant called stock, is called grafting. 
  • Where as budding is also called bud grafting in which only one bud is joined on the stock.
  • e.g. Apple, Pear, Rose, etc.
c. Tissue culture : 

  • It is a method by which a small amount of plant tissue is carefully grown to give many plant lets. 
  • Micropropagation method is also used now a days.

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