Mineral Nutrition

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ÇRÏTËRÏÅ FØR ËSSËÑTÏÅLÏTÝ ØF ÅÑ ËLËMËÑT

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The element must be necessary for normal growth and reproduction. In

the absence of the elements the plant do not complete their life cycle

or set the seeds. The requirement of an element must be specific i.e.,

deficiency of an element cannot be met by another element. It must be

directly involved in the plant metabolism. Only 17 elements are absolutely

essential for plant growth and metabolism.

Based on quantitative requirements, essential elements are of 2 types:

Macronutrients & Micronutrients.

1. MÅÇRØÑÜTRÏËÑTS

They are present in

plant tissues in large

amounts (more than

10 mmole Kg^-1 of dry

matter).

They include

carbon, hydrogen,

oxygen, nitrogen,

phosphorus,

sulphur, potassium,

calcium &

magnesium.

C, H & O are mainly

obtained from CO2

& H2O. Others are

absorbed from soil

as mineral nutrition.

1

2

3

2. MÏÇRØÑÜTRÏËÑTS (TRÅÇË ËLËMËÑTS)

01

They are needed in very small amounts (less than 10

m mole Kg^-1 of dry matter).

They include iron, manganese, copper, molybdenum,

zinc, boron, chlorine and nickel.

02

Higher plants also need sodium, silicon, cobalt,

selenium, etc.

03