07 Plant Growth and Mineral Nutrition - part 07 - Development and Plasticity

07 Plant Growth and Mineral Nutrition - part 07 - Development and Plasticity


Development: 


  • Refers to the ordered or progressive changes -  
  1. in shape
  2. form and 
  3. degree of complexity. 
  • It includes all the changes occurring in sequence from the germination of seed upto the senescence or death during life cycle of plants. 
  • Thus development includes -  
  1. growth
  2. morphogenesis
  3. maturation and 
  4. senescence.
Plasticity : 
  • It is the capacity of being moulded, formed or modeled. 
  • It is the ability of plants to form different kinds of structures (i.e. to change) in response to different environmental (external) or internal stimuli, in various phases of life. 
  • In many plants, juvenile stage and mature stage show different forms of leaves in the same plant.
  • e.g. heterophylly in cotton, coriander, larkspur (Delphinium). 
  • The environmental heterophylly is shown by Ranunculus flabellasis (butter cup). 
  • The intrinsic plasticity is found in coriander and cotton. 
  • Heterophylly is exhibited in the same plant in different growth phases or under different environmental conditions.

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