Cauliflower (Brassica oleracea var. botrytis)

Nitrogen (N)

Symptoms

  • Deficiency symptoms will be first noticed in older leaves.
  • Leaves becomes yellowish-green
  • Death and / or dropping of the older leaves.
  • Stunted plant growth
  • Pale, small and thick fruits
  • Red discoloration at the margin of older leaves
  • Poor root system

Management

  • For determining the severity of the deficiency, soil analysis has to be done
  • Application of quick releasing nitrogen fertilizer like urea, according to the results of the soil test.
  • Apply urea as a foliar spray (10 gram per litre of water) once every 15 days
  • Frequent application of organic growth boosters is also beneficial

Phosphorus (P)

Symptoms

  • Deficiency symptoms will be first noticed in older leaves
  • Purpling of the leaves, particularly the leaf veins
  • Stunted growth of plants.
  • Short and thin shoots
  • Reduced vigor and yield

Management

  • Ensure that recommended amount of fertilizer is applied on regular time.
  • For determining the severity of the deficiency, soil analysis is to be done
  • Use fertilizers such as single superphosphate for quick correction or bone meal or rock phosphate for long-term correction.
  • In the pH range of 6.2-7.0, phosphorus is readily absorbed by the roots.
  • Addition of biofertilizers including phosphorus solubilizing bacteria along with organic manure helps to increase the availability of phosphorus

Potassium (K)

Symptoms

  • Deficiency symptoms will be first noticed in older leaves
  • Yellowing and scorching of leaves
  • Leaf margins turn yellow to light brown, later dark brown
  • Crinkled leaf surface
  • Leaf margins are cupped upwards
  • Leaves are less waxy
  • Reduced growth, weak stems, and shoot die-back
  • Decresed number of female flowers

Management

  • In the pH range of above 6, potassium is readily available.
  • Maintain pH by addition of lime/dolomite
  • Improve the soil fertility by adding organic matter and wood ash.
  • For determining the severity of the deficiency, soil analysis is to be done
  • Use Muriate of Potash (MOP) according to the results of the soil test. Split application is preferable.
  • Apply foliar sprays of Sulphate of Potash (SOP) (10 g/litre of water) and wetting agents in the morning as an immediate remedy

Calcium (Ca)

Symptoms

  • Deficiency symptoms will be first noticed in younger leaves
  • “claw like " deformation of youngest leaf
  • Reduced leaf growth
  • Marginal necrosis of young leaves
  • Reduced internodal length and rosetting of leaves
  • Stunted growth of plants
  • Leathery and brittle leaves.
  • Upward cupping of leaves.
  • Leaves are distorted with hooked tips
  • Smaller and tasteless fruit may fail to develop
  • Reduced and stunted root growth

Management

  • Do the soil analysis
  • Check the pH of the soil. If the soil is extremely acidic (pH between 3.5 and 4.5), apply lime (3.4 kg/cent in two split doses). And in areas of moderate acidity (pH between 5.5 and 6), apply lime 1 kg/cent.
  • High phosphorus levels lead to calcium deficiency.
  • In alkaline soil application of Gypsum is preferable
  • Boron is needed for calcium utilization.
  • So, a boron deficiency can also lead to calcium deficiency.

Magnesium (Mg)

Symptoms

  • Symptoms first appear on older leaves
  • interveinal chlorosis.
  • The small veins also become chlorotic, but the bigger ones remain green
  • Spotted necrosis on leaves
  • Stunted growth of plants
  • Reduced leaf growth
  • Poor rooting
  • Premature leaf abscission
  • Reduced fruit yield

Management

  • Do the soil analysis and confirm the deficiency.
  • Addition of Magnesium sulphate (32 kg/ acre) in bands near plants.
  • Long-term usage of dolomite will reduce magnesium deficiency
  • Magnesium and potassium fertilizers should not be applied together

Sulphur(S)

Symptoms

  • Deficiency symptoms first appear in younger leaves.
  • Chlorosis followed by general yellowing
  • Young leaf become purplish in colour
  • Upward curling and roll in of leaves
  • Stunted growth of plants
  • Death of seedlings

Management

  • Application of sulphur-containing fertilisers, such as Factamfos, Ammonium sulphate, Single superphosphate, etc., reduces the deficiency.
  • In sulphur deficient soils, apply sulphur dust (10 kg/acre).
  • Deficiency in alkaline soil can be reduced by application of gypsum
  • Addition of organic material improves sulphur availability in the soil
  • Burning of organic waste leads to sulphur deficiency

Boron (B)

Symptoms

  • Deficiency is seen mainly in younger leaves
  • Distortion of newer leaves and broad yellow border at the margins of the oldest leaves
  • Leaf margins turn reddish or brown in colour
  • Downward curling of leaves
  • Death of all buds
  • Fruit size and colour is affected
  • Reduced yield and quality of fruits
  • Mottled yellow longitudinal streaks on fruits lead to corky marking( scurfing)

Management

  • Analysis of soil to confirm the deficiency.
  • Application of borax (4 kg/ acre) into the soil
  • Addition of borax (1 gram / litre of water) as foliar spray
  • Avoid the combined application of Boron and calcium.
  • Application of borax with ammonium fertilizers should be avoided.

Iron (Fe)

Symptoms

  • Deficiency symptoms first appear on young leaves
  • Interveinal chlorosis
  • Yellow leaves with dark green veins
  • Entire plant become light green in colour
  • stunted plant growth
  • Reduced root growth

Management

  • Iron content in Kerala soils is often high. So, get a soil test to determine the reason for the problem
  • Low potassium levels lead to iron deficiency
  • Addition of Ferrous Sulphate (6 kg/ acre) into the deficient soils.

Manganese (Mn)

Symptoms

  • Deficiency symptoms first appear on those leaves just reaching their full size
  • Marginal chlorosis of young leaves
  • Younger leaves brighten whereas the veins remain green
  • Interveinal mottled chlorosis
  • Necrosis on chlorotic area
  • Reduced leaf size
  • Crimping of leaf margin

Management

  • Soil Analysis
  • Application of Manganese Sulphate (2 gram per litre of water) as foliar spray

Zinc (Zn)

Symptoms

  • deficiency symptoms first appear on young leaves
  • Interveinal chlorosis of leaves with whitening
  • Leaves are small and distorted with a rosette form.
  • Curd colour is effected
  • Stunted growth of plants

Management

  • The optimal pH range for zinc availability is 5 to 7.5.
  • Confirm deficiencies by doing soil testing.
  • Apply zinc sulphate to deficient soils (8 kg/ acre)
  • Avoid the application of zinc and phosphate fertilizers at the same time
  • In severe cases, foliar spraying of zinc sulphate (2 gram/litre of water) with Calcium carbonate (2.5 gram/litre of water) can be advocated in morning hours.

Molybdenum (Mo)

Symptoms

  • Distorted leaves with reduced leaf area
  • Interveinal chlorosis with dark green main veins
  • "Whiptail" formation
  • chlorotic leaf margins
  • In severe cases the whole leaf turns yellowish

Management

  • Soil application of 1.0 kg sodium molybdate /ha
  • Foliar spray of sodium molybdate 0.1%
  • Soil application of 120kg N, 75 kg P and Mo 1.5kg/ha, 1 kg B/ha