07 Plant Growth and Mineral Nutrition - part 05 - Growth curve

07 Plant Growth and Mineral Nutrition - part 05 - Growth curve


Growth curve : 
  • It is a graphic representation of the total growth against time. 
  • There are three types of curves viz, 
  1. Linear
  2. Exponential and 
  3. Sigmoid. 
1. Linear curve
  • Arithmetic growth curve is linear.
2. Exponential Curve :

  • Geometric growth curve is exponential. 
  • Corresponding to three distinct phases of growth, growth rates differ. 
  • In Lag phase, growth rate is slow. 
  • In Exponential (Log) phase, growth rate is faster and reaches its maximum. 
  • In Stationary phase, growth rate gradually slows down. 






3. Sigmoid Curve :

  • When a graph of rate of growth against time is plotted for three phases of growth, a sigmoid curve is obtained.
  • The total time (period) required for all phases to occur, is called Grand Period of Growth

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