A brief Description- Micronurients in Plants

 MICRO NUTRIENTS

Micronutrients play complex roles in plant development and health. Micronutrients promote remarkable  growth of crops that produce higher yields .These  nutrients also  increase the quality of nutrients present in plants. The presence of micronutrients renders the  big impact on root development, fruit setting ,seed viability and plant vigor and health.

IRON

Absorption 

Plants withdraw iron in the form of ferric ions.

Role

Iron is a  constituent of proteins or enzymes that are involved in the transfer of electrons and activates catalase enzymes.

It is essential for the formation of chlorophyll.

Deficiency & Symptoms 

Interveinal chlorosis is the main symptom of iron deficiency in plants. Manganese is another micronutrients that is responsible for iron deficiency in plants because it interferes in absorption of iron from soil. If there is too much waterlogging in soil it deviates the pH of soil. As a result, iron absorption by plants is affected. 

The  symptom of iron deficiency is chlorosis of the young leaves. At the beginning , a yellow interveinal chlorosis develops and makes a green appearance of veins in leaves. In severe cases  the chlorosis becomes white and the veins may lose their green colour.

Leaf blades show necrosis. and may be visible from the tip to interveinal zones. Necrotic tissue  is generally light brown in color.

           MANGANESE

Absorption

Manganese is absorbed in the form of manganese ions.

Role

It activates many enzymes and helps in splitting of water to liberate oxygen during photosynthesis.

Deficiency & Symptoms

Manganese deficient plants possess interveinal chlorosis mainly in young leaves and a major portion of leaves near the vein become green.

Leaves, shoots, fruits or stems may be distorted  and plant parts may be reduced in size. Necrosis is also seen in parts of plants. Interveinal necrosis or necrotic spotting is also typical of Manganese deficiency in some species.  If plants are grown in alkaline soils then Manganese deficiency may frequently appear.

                   

ZINC

Absorption

Plants obtain zinc from soil in the form of zinc ion.

Role

Zinc activates enzymes like carboxylases and is also needed in the synthesis of auxin. Zinc is  related with Nitrogen,carbohydrate and lipid metabolism of plants. It has a vital role  in protein and RNA synthesis. Zinc also influences the root membrane permeability.

Deficiency & Symptoms

zinc deficiency makes the leaf  yellow but  leaf veins remain green and  young leaves are  more affected. New leaves are smaller and narrower and have wavy margins. If deficiency remains, then  the yellow spot or chlorotic spots may turn into bronze color. Necrosis may occur at the  margins of leaves.. Zinc-deficient leaves have small internodes. 

                  

COPPER

Absorption

Copper is absorbed as cupric ions .

Role

It is essential for the overall metabolism in plants and involved in redox reactions.

Copper is essential for some enzymes in plants which are involved in lignin synthesis.

It is also required in the process of photosynthesis.copper regulates the  plant respiration and  carbohydrates and proteins metabolism.

Deficiency & Symptoms

Copper is immobile therefore early symptoms appear  in the newer leaves. Symptoms The chlorosis  occurs on  the whole leaf or between the veins of the new leaves. Sometimes small necrotic spots may be visible at the chlorotic area. 

In the severe cases, the new leaves are smaller in size,and may wilt soon. The apical meristems may die therefore  the growth of lateral branches does not occur. Flower color is also affected due to zinc deficiency.

                

 BORON

Absorption

Boron is absorbed in the form of boric acids or borate ions.

Role

Boron required for uptake and utilisation of Calcium in plants. It regulates the function of cell membranes. It is essential for pollen germination.

Deficiency & Symptoms

Due to the lack of Boron, Young leaves are curled. Plants growth are stunted at some growing tips. Leaves are very small and may be present in the form of rosettes.The size of seeds may be very small. The lower leaf tips become yellow.  

MOLYBDENUM

Absorption

Plants obtain molybdenum in the form of molybdate ions.

Role

Molybdenum is a component of several enzymes like nitrogenase and nitrate reductase.It mainly regulates nitrogen metabolism in plants. It plays an important role in the conversion of  nitrate into nitrogen in their leaves because nitrogen is an essential for the formation of  protein.The root nodule bacteria in  legumes plants need molybdenum to fix atmospheric nitrogen.

Deficiency & Symptoms

The plant  shows  stunted growth. The  leaves appear pale green or yellowish green in colour between the veins .The older leaves may be more severely affected.

              

   CHLORINE

Absorption

Chlorine is absorbed in the form of chloride anion.

Role

Chlorine maintains the solute concentration and the anion cation balance in cells.

It is essential for the water-splitting reaction in photosynthesis. It is also involved in the opening and closing of stomata.

Deficiency & Symptoms

Chlorine deficiency causes chlorosis and necrosis.  The leaves develop irregular boundaries between the affected and healthy tissue. In severe cases, bronzing and wilting of leaves takes places.