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A Handbook of Biology

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All organisms require macromolecules (carbohydrates, proteins, fats,

etc.), water & minerals for growth and development.

MËTHØDS TØ STÜDÝ THË MÏÑËRÅL RËQÜÏRËMËÑTS ØF PLÅÑTS

The technique of

growing plants in

a defined nutrient

solution (without

soil) is known as

hydroponics.

Hydroponics is

used to identify the

essential elements

required for plants

and their deficiency

symptoms.

Hydroponics

technique was first

demonstrated by Sir

Julian Von Sachs

(German botanist,

1860).

In this, plant roots

are immersed in

nutrient solutions

and an element

is added/

removed in varied

concentrations.

The nutrient solution

is aerated for

optimum growth.

Hydroponics is used

for commercial

production of

vegetables such as

tomato, seedless

cucumber & lettuce.

01

02

03

06

05

04

ËSSËÑTÏÅL MÏÑËRÅL ËLËMËÑTS

1

Out of 105 discovered elements more than 60 elements are

found in different plants.

2

Some plant species accumulate selenium, gold, etc.

Plants growing near nuclear test sites take up radioactive

strontium.

3

There are techniques to detect the minerals even at a

very low concentration (10^-8 g/mL).