Calcium (Ca) deficiency symptoms

Calcium (Ca) deficiency symptoms:

• Young leaves show interveinal chlorosis near the margins and towards the tip. 
• When these chlorotic patches die they create a serrated necrosis along the leaf margin. 
• A temporary shortage of calcium causes the “spike leaf” symptoms in the field in which the lamina of new leaves is deformed or almost absent with thickened lateral veins near the mid-rib and deficient root system which is susceptible to rot. 
• Fruit quality is inferior and the peel splits when the fruit is ripe.

(Boron and Calcium deficiency symptoms tend to overlap. So see Boron deficiency pictures also).

Picture 1: Ca deficiency-Early foliar symptom - 
Yellow stripes parallel to leaf midrib.

         
Picture 2:  Ca deficiency-Early foliar symptom - 
Yellow stripes parallel to leaf midrib.

        Picture 3: Early foliar symptom of Calcium and Boron deficiency -           WRINKLED LEAF.

        

          Picture 4: Boron & Calcium deficiency - deformed and whitish heart leaf. 

        
Picture 5: Boron and Calcium deficiency - "SPIKE LEAF" (in which the        lamina of new leaves is deformed or almost absent). 

 

(Photos credit: ctahr, Hawaii)

Control Measures:

         

a.     Drip fertigation of Calcium Nitrate (CaNo3) @ 4 kg/1000 plants every 4^th day upto 5^th month.

                                                (OR)

b.     Manual application of Calcium nitrate (CN)) @ 40g/plant per month upto 5^th month and if necessary till finger development. Application of CN  provides calcium as well as nitrogen (15.5-0-0 + 19% Ca) to the soil, therefore quantity of nitrogen needs to be adjusted with the total nitrogen requirement of the soil.

The picture below shows a plant affected due to Calcium and Boron deficiency and the subsequent recovery after the remedial measures taken as under:

Step 1: Drenching the growing shoot (by applying inside the emerging unfurled funnel shaped leaf) with 100 ml of foliar grade boron rich micronutrient solution.

Step 2: Fertigation of Calcium Nitrate @ 20 gm / plant (in 2 split doses).

Note: If the deficiency is severe, 3 to 4 foliar applications of micronutrients have to be given to the crop up to 7 months along with fertigation of Calcium Nitrate @ 75 gm / plant in 5 to 7 split doses.

 

Sources of Calcium:

Lime

Soil amendment which is commonly used to raise the pH of the soil.

Calcium Carbonate

Approximately 38% Ca, depending upon its source

A common liming material, calcium carbonate also supplies calcium to the soil.

Dolomite

22% Ca and 12% Mg, depending upon the dolomite source

In addition to raising the pH, dolomite is a source of calcium and magnesium.

Gypsum

23% Ca and 19% S

Unlike liming materials, gypsum does not increase the soil pH.

In addition to providing calcium and sulfur, gypsum may be used to correct soil physical problems and/or aluminum toxicities.

Calcium nitrate

15% N and 20% Ca

Calcium nitrate is very soluble in water.

Superphosphates

Single (SSP)

18-21% Ca

SSP supplies both calcium and phosphate.

Triple (TSP)

12-14% Ca

Like SSP, TSP supplies both calcium and phosphate

Regards,
A.Vishnu Sankar