Essential Nutrients

By Daniele Schafer

 

You may think that plants only need sunlight and water to germinate a seed, grow a leaf, flower and produce a fruit in some cases, but plants need much more for their survival than that. In order for plants to have a normal and health life cycle, they also need minerals.

Bellow is a compiled table of some of the most important micro- and macro- elements. The table is display in reference of their nutrient deficiency, following by the significance for the plant cell, then the cause of deficiency, and finally the visible phenotype expression observed on plants.

Specific Vocabulary:

• Chlorosis: yellowing due to loss of chlorophyll (see also article)
• Necrosis: dead tissue
• Microelement and Macroelements are reflection of relative concentration found in tissue or required in nutrient solutions (see also article).
• Macroelement: they are required in large amounts

• Microelement: they are required in relatively small quantities

 

Macro

-P    (Phosphorus)

DNA, RNA, ATP

When soil has ph 6.8 and higher, which difficult the absortion by the roots

• intense green
• fruit and seed decline
• necrotic spots
• malformation

Macro

-K   (Potassium)

Ionic balance in cells

Sandy soils

• chlorosis
• mottled leaves
• root fungal infection
• leaf tip brown/burn

Macro

-S    (Sulfur)

Protein and vitamins

Deficiency of microorganism capable of oxidizing sulfides or  decomposing organic sulfur compounds

• chlorosis aroung vascular bundle
• reduced protein synthesis

Macro

-Ca  (Calcium)

Cell wall

Seldom deficient under natural conditions

• meristem death (necrosis)
• poor root growth

Macro

-K   (Potassium)

Ionic balance in cells

Sandy soils

 

Macro

-S    (Sulfur)

Protein and vitamins

Deficiency of microorganism capable of oxidizing sulfides or  decomposing organic sulfur compounds

 

Macro

-Ca  (Calcium)

Cell wall

Seldom deficient under natural conditions

 

Micro

-Mg (Magnesium)

Chlorophyll molecules

When soil is strongly acid, sandy soils

• leaf vein chlorosis (yellowing)

Micro

-Fe  (Iron)

Photosynthesis  and respiration

Propensity of Fe3+ to form insoluble hydrous oxides.

In neutral or alkaline calcareous soil

 

• loss of chlorophyll
• chlorosis, whiteness

Micro

-Cu  (Copper)

Photosynthesis

When soil is not aerated, which little oxygen used to reduce Cu2+to Cu

• curled ,downward pointing leaves
• loss of turger
• light chlorosis

Micro

-B    (Boron)

Exact role unclear

When soil has ph>8

• light overall chlorosis

Micro

-Mn (Manganese)

Respiration and nitrogen metabolism

If soil ph < 6 and have high organic content

• chlorosis in young leaf vein
• greenish-gray on young leafs
• deformities in legumes seeds

Micro

-Cl   (Chlorine)

Ionic balance in cells

Hardly deficient (only seeing in controlled solution)

• abnormal shaped leaves
• vein chlorosis
• wilting of the leaf tips

Micro

-Ni   (Nickel)

Uncertain

Not completed understood, some how related to seed content

• depressed seedling vigor
• chlorosis
• necrotic lesions in leaves

Micro

-Mo (Molybdenum)

Nitrogen metabolism

If soil is acid with high content of iron precipitates, which absorbs the element

• mottled spotting
• vein chlorosis
• upward leaf curling
• if severe leaves turn bright orange

Micro

-Zn   ( Zinc)

Respiration and nitrogen metabolism

Disturbances in metabolism of the hormone Auxin

• vein necrosis
• small leaves
• short stems