- Overall reduction in growth.
- Leaves become uniformly light-green or yellow. Reddening of petiole
- Berries may be small
- Soil application of urea @ 20-60 Kg/acre
- Foliar spray of urea (0.3 – 0.5%) 1- 4 times along the growing season , depending on the deficiency severity.
- Starts as yellowing (white varieties) or bronze-reddening (red varieties) of olderleaf margins.
- As the deficiency worsens, leaf margins become necrotic and curl upwards and inter-vein alchlorosis develops.
- Berry set can be poor.
- Soil application of 200- 320 Kg K2O/acre for 2-3 years
- Foliar sprays of sulphate of potash (0.4 -1%), 3-4 times every 15 d before and after flowering.
- Other commercial fertilizers containing K can be used
- Bright yellow (white varieties) or red (red varieties) wedge-shaped areas extend inwards between the veins on older leaves.
- When severe, necrosis extends inwards from the leaf margins.
- Fruit cluster stem necrosis and berry withering
- Soil application of 20-40 Kg MgO/acre
- Foliar application of Magnesium sulphte (2%if MgO =32% or if MgO = 16%) or magnesium chloride /nitrate (1-1.5%) 3-6 times every week, beginning from fruit set
- Sprays against stem necrosis by magnesium sulphate (as above).
- Vines may have stunted shoots and fruitfulness is likely to be poor.
- Appearance of red dots on basal leaves, especially on the mid or terminal lobes and at first distant from secondary veins.
- The red dots, at first randomly distributed, later line up at right angles to the secondary veins and form dark red bars, which coalesce into islands between green veins.
- Apply ammonium mono phosphate as an N source (11-52-0).
- Reddening of young leaves. Red dots near the edges of adults leaves. Red dots may coalesce later into red bars at right angles to the vein leaves can drop
- Reduced growth lignification is impaired
- Small and loose cluster, due to reduced fruit set
- Soil application of 20-40 Kg/acre P2O5
- Shoot tip death and short internodes, resulting in shoots with a zigzag appearance.
- Yellowing or reddening dots rolling down, corrugation and odd shapes in young leaves
- Fruit set is often poor and bunches often have „hen and chicken‟ berries
- Browning of hypodermal cells and breaking of berry
- Soil application of borax(Sodium tetraborate) 12-32 Kg/acre
- Foliar application of solubor(20.5%B),0.25% 3 times every 15 days ,beginning from 5th -6th leaf development stage.
- Young leaves show interveinalchlorosis.
- When severe, leaves are likely to be very pale with necrotic blotches. Shoots are likely to be stunted in their growth.
- Loose cluster shot berries
- Soil application of Fe-EDTA or foliar application of Ferrous Sulphate (250g/100 litre water) + citric acid (50g) + liquid detergent
- Stunted growth
- Interveinal chlorosis or reddening of adults leaves. mosaic like arrangement of yellow /red spots, bordered by the smallest green veins
- Delay of berry ripening
- Foliar sprays of manganese sulphate (0.2 -0.5%) , 3 times, one before and two after flowering
- Foliar sprays of Manganese chelates.
- Short internodes, resulting in shoots with a zigzag appearance
- Shoot tips have small upward curling of leaves.
- Mottled, light coloured interveinal colouring on leaves. Small, poorly developed bunches with hen and chicken berries.
- Soil application borax (sodium tertaborate) 12-16 Kg/acre
- Foliar sprays of zinc sulphate (0.5 -1.0%) neutralized with calcium carbonate,3 weeks before flowering
Source: NIPHM, NCIPM and Directorate of Plant Protection, Quarantine & Storage