Essentiality of elements in plant nutrition

Definition :
A mineral element is considered essential to plant growth and development if the element is involved in plant metabolic functions and the plant cannot complete its life cycle without the element. Usually the plant exhibits a visual symptom indicating a deficiency in a specific nutrient, which normally can be corrected or prevented by supplying the nutrient. 

Terms commonly used to describe levels of nutrients in plants  :

Deficient: When the concentration of an essential element is low enough to limit yield severely and distinct deficiency symptoms are visible. Extreme deficiencies can result in plant death. With moderate or slight deficiencies, symptoms may not be visible, but yields will still be reduced.

Critical range: The nutrient concentration in the plant below which a yield response to added nutrient occurs. Critical levels or ranges vary among plants and nutrients, but occur somewhere in the transition between nutrient deficiency and sufficiency.

Sufficient: The nutrient concentration range in which added nutrient will not increase yield but can increase nutrient concentration. The term luxury consumption is often used to describe nutrient absorption by the plant that does not influence yield.

Excessive or toxic: When the concentration of essential or other elements is high enough to reduce plant growth and yield. Excessive nutrient concentration can cause an imbalance in other essential nutrients, which also can reduce yield.

  

  

  

Essential Nutrients for plant growth and their principal forms for uptake

Nutrient	Chemical Symbol	Principal forms for uptake
Carbon	C	CO2
Hydrogen	H	H2O
Oxygen	O	H2O, O2
Nitrogen	N	NH+4, NO-3
Phosphorus	P	H2PO-4, HPO2-4
Potassium	K	K+
Calcium	Ca	Ca2+
Magnesium	Mg	Mg2+
Sulfur	S	SO2-4, SO2
Iron	Fe	Fe2+, Fe3+
Manganese	Mn	Mn2+
Boron	B	H3BO3
Zinc	Zn	Zn2+
Copper	Cu	Cu2+
Molybdenum	Mo	MoO2-4
Chlorine	Cl	Cl-

click on an ad to support us :)