This document discusses important physiological disorders that can occur in bananas, including choke throat, chilling injury, kottai vazhai, finger drop, and peel browning. Choke throat results from low temperatures during flowering and causes yellowing and necrosis of leaves, extending maturity time. Chilling injury occurs below 14°C and causes uneven ripening and brown streaks. Kottai vazhai produces sharp, ill-filled fruits with a seedy core, reducing yields. Finger drop causes the fruit pedicle to weaken, allowing individual fruits to detach easily. Peel browning occurs during maturation when sensitive varieties are handled.

1. IMPORTANT PHYSIOLOGICAL
DISORDERS IN BANANA
BY
SIVASAKTHI SS
2021004104

2. INTRODUCTION:
• Physiological disorders in different fruit crops results from change in
environmental conditions.
• Including sunlight, aeration, temperature and nutritional imbalance.
• These disorders result in decrease in fruit quality and quantity.
• These disorders are also arise from micronutrient deficiency.

3. 1. CHOKE THROAT
Symptoms:
• It results from low temperature.
• At the time of flowering,it effects bunch formation.
• Due to low temperature, yellowing of leaves occurs.
• Under severe conditions,leaves become necrotic.
• Maturity time of bunch is extended upto 5-6months than 3.5-4 months.
Management:
• Use eucalyptus as shelter belt check effect of cold wind.

4. 2.CHILLING INJURY:
Symptoms:
• It happens when the pre or post harvest temperature falls below 14’c.
• It includes uneven ripening,watery dark patches on skin.
• Dull yellow to smoky yellow color of the ripening fingers.
• Brown streaks are also observed on vascular bundle of the sub epidermal layer.
Management:
• Avoid to Store the fruits at temperature below 13’c.
• Storing at a temperature above threshold level.

5. 3.KOTTAI VAZHAI
Symptoms:
• It characterized by presence of sharp tapered and ill filled fruits.
• It have seedy structure in central core.
• It makes the fruits inedible.
• Symptoms of this disorder do not appear at earlier stages.
• It results in 10-25% reduction in yield.
Management:
• By spraying 20ppm(1g in 50L of water) 2,4-D.
• By applying these seediness of fruits can be controlled.

6. 4.FINGER DROP
Symptoms:
• In this disorder,the pedicle become soft and weak.
• Individual fruits can be dissociated from the bunch very easily
during ripening.
Management:
• Use carton for packing of fruit bunches.
• Provide ventilation and temperature of 18’c to fruits for ripening.

7. 5.PEEL BROWNING
Symptoms:
• This disorder occurs during maturation process when fruit is handled.
• Fruit handling will promote browning if the variety is sensitive.
• Some varieties seems to be more sensitive than others.
• Symptoms develops in entire banana surface.
Management:
• Storing fruit at high relative humidity (95%).
• It delays peel browning.