Physiological disorders
a) Kottavazhai:
- It has peculiar development disorder which is characterized by the presence of distinctly conical and ill filled fruits with a prominent central core having many under developed non-viable seedy structures rendering the fruits inedible.
- This disorder can be overcome by spraying 2,4 D 20 ppm when the last hand of bunch is opened.
- The same chemical at same dose and same stage results in increased bunch weight and uniform grade especially in cvs. Nendran and Monthan.
b) Hard lump:
- It is characterized by pinkish brown, firm pulp than the usual soft pulp occurs in cv.Rasthali, tastes like immature or unripe fruits.
- Spraying the bunches uniformly with 2,4 D at 1000 ppm or dipping the cut end of peduncle of the bunches for a period of 5 minutes appears to favor the reduction of lumps and improve the size.
c) Sunscald:
- The peduncle of the bunches may be covered with flag leaf to prevent
- ‘main stalk rot’ and also the bunches with banana leaves to avoid sunscald.
d) Nematode:
