Nutritional Disorders in Crops

 Low supply or complete absence of any of the essential elements will exhibit typical

symptoms, which are specific to the particular elements(s). This condition is called

nutrient deficiency and the symptoms as deficiency symptoms.

In the absence or low supply of elements (deficiency), the following common symptoms generally

develop in the plants.

General Deficiency Symptoms

1. Chlorosis

It is a physiological disease that occurs due to a deficiency of mineral elements.

(eg. N, K.Mg, Fe, Zn, Mn, S). Leaves become abnormally yellow or white due to the reduction of

chlorophyll contents.

2. Mottling

It is a condition of plant surface marked with coloured spots due to anthocyanin pigmentation

(eg. due to deficiency of N, K, Mg, P, S)

3. Necrosis

It refers to the patch of dead tissues, due to deficiency of K, Mg, Zn, Ca, Mo, Mn, Fe, or B.

4. Bronzing

Development of bronze/copper colour on the leaves and various parts (eg. K)

5. Dieback

The collapse of growing tip, affecting the youngest leaves and buds (eg. K, Ca, B or Cu)

6. Scorching

Burning of tissues accompanied by light brown colour. (eg. K, Ca, B or Cu)

7. Firing

Burning of tissues accompanied with dark brown or reddish-brown colour (eg. Mg)

8. Rosetting

Clustering of leaves due to reduced leaf size and shorter internodal distance (eg. Cu, K, Zn)

9. Distortion of leaves

Irregular shaping of leaves like cupping, twisting, hooking or curling and also wavy margins.

Cupping: B or Mo

Twisting / Hooking: Zn/Ca/B

Curling: Ca, B or Zn

Head distortion: Cu (rice), Mn(Sunflower)

Wavy: Zn

10. Gummosis

Oozing out of cell sap in the form of gummous nature (eg. Cu as in coconut etc.)

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