2. Tomato
• Botanical name Solanum lycopersicum
• Primary centre of origin Peru
• Secondary centre of origin Mexico
• Popularly known as Poor man’s Orange
3. Physiological Disorder
Physiological disorder is the abnormal growth pattern or
abnormal external or internal conditions of fruits due to
adverse environmental conditions such as deviation
from normal state of temperature, light, moisture,
nutrient, harmful gases and inadequate supply of
growth regulators.
4. Physiological disorders in tomato
1. Blossom End Rot
2. Cracking of fruits
3. Puffiness/ Hollowness
4. Sunscald
5. Cold Injury or Low temperature injury
6. Blotchy Ripening
7. Cat face
8. Gold fleck
5. Blossom End Rot
Symptoms :
•A very common and destructive disorder .
•Rotting of fruits starts at blossom end of the fruit.
•A brown or water soaked discoloration near the blossom
end (opposite the stem end) of the fruit.
•Affected portion becomes sunken, leathery and dark
colored
•Fruit do not soft rot unless the spots are invaded by
secondary organisms.
• Deficiency of Mg and Ca is the
main cause .
6. Management
•It can be managed by spraying calcium chloride @ 0.5%
at fruit development stage.
• Apply balanced irrigation and ensure proper staking .
• Misting or Fogging inside the green house reduces the
incidence.
• Use of Polythene mulch to maintain adequate soil
moisture.
7. Cracking of fruits
Symptoms:
• Radial cracking is more severe than concentric cracking
• Cracking start from stem end in ripe fruits
• Concentric crack around the shoulders of green fruit
• Fruit cracking is most common on the large-fruited
varieties.
Causes:
Heavy rainfall or irrigation following a long, dry period
promotes rapid growth during ripening.
9. Management
•Maintain optimum soil moisture
•Grow resistant cultivars .Ex:-pusa ruby, Sioux, Roma,
Arka saurabh
•Soil application of 20-30 kg of borax per hectare is
beneficial .
• In the greenhouse or conservatory, control
temperature and sunlight levels carefully to avoid
extremes, using combinations of heating, ventilation
and white greenhouse paint as appropriate
10. Puffiness/ Hollowness
Symptoms:
• Puffiness refers to existence of open cavities between
the outer walls and locular content in one or more locules
and is also known as hollowness or boxiness.
• The outer wall continues to develop but the growth of
remaining internal tissues is retarded. This results in light
weight fruits which lack firmness and are partially filled
11. Causes of puffiness :
•Non fertilization of ovules
•Embryo abortion after normal fertilization
•High temperature and high soil moisture are
predisposing factors.
12. Management
• Maintaining optimum soil moisture.
• Avoid over irrigation.
• Single application of 4-CPA @ 20mg/litre or CPPU @
20-25mg/litre results in reduction of this problem.
13. Sunscald
Symptoms:
• Green or near green of fruits exposed to sun light.
• The tissues have blistered, water soaked appearance .
• Rapid desiccation leads sunken area on ripe fruits.
• More sun intensity cause injury to fruits in May & June
(11-3 pm) during peak heat period.
14. Management
•Grow varieties having heavy foliage which provide
greater protection to fruits from sun rays.
•Crop are planted at higher densities are less susceptible
•Cultivation of indeterminate/ semi- determinate varities
without staking.
15. Cold Injury or Low temperature injury
Tomato is very sensitive to frost. At near freezing
temperature, vines freeze, get withered and desiccated.
Fruits show much severe symptoms as they become soft,
water soaked and dull coloured.
Management
Cover the fruits with foliage to manage this problem.
Planting should be adjusted in such a way that it does not
coincide with frost.
16. Blotchy Ripening
Symptoms:
•Ripening of fruits is not uniform as certain portion
develop colour while in others greenish-yellow or
whitish patches can be seen on ripe fruits particularly in
stem end portion.
•This disorder is also known as the grey wall.
Causes :
•The possible reasons are imbalance of N and K nutrition
especially when K is deficient.
•Even, more days or weeks of alternate sun and cloud
during fruiting also lead to blotchy ripening
17.
18. Management
• Regulated water supply during fruit development .
• Foliar sprays of 0.5% potassium chloride.
• Adjust planting date to achieve favorable light intensity
for good fruit development.
19. Cat face
Symptoms:
• The fruit gets distorted at the blossom end.
• The fruits have ridges, furrows, indentations and
blotches
• The cells at blossom end of the ovary die and turn
black and forms leathery blotch
20. Causes:
• Unfavorable climatic condition during flowering
causes distortion of growth of the pistil cells.
Control:
•Grow varieties free from this distortion .
•Grow tomatoes in the ample growing conditions.
• Recommended cultural practices should be adopted.
21. Gold fleck
Symptoms:
•Gold specks or flecks are often observed around the
calyx and shoulders of mature fruit, particularly in
summer.
•Tiny yellow spots appear on the fruits surface around
the calyx and fruit shoulder.
22. Causes:
• Higher supply of calcium and phosphate fertilizers.
• Excess calcium oxalates
Management:
•Apply recommended dose of calcium and potassic
fertilizers.
• Provide shade during summer season
