Onion Thirteenth to fourteenth week practices

Onion Smudge:

It occurs on white onion varieties and reduces the market value of the bulbs. The disease is characterized by small dark green to black spots, which appear on the outer scales.

Control: 

Thorough curing of the bulb after harvesting and storing the bulbs in well ventilated rooms can control the disease

Black Mould:

The disease is common in onions stored in hot climates where the temperature ranges between 30- 45⁰C. It is characterized by the black powdery mass of spores that appear on the exterior of the scales. The black spore masses are also seen on inner scales. It reduces the market value of the bulbs.

Control: 

For effective control of die disease, leave it to dry in the field for two days. These bulbs should be further dried in shade for 10-15 days before storage. Care should be taken to avoid injury to the bulbs during post-harvest handling. The crops should be sprayed with Carbendazim (0.2%) 10-15 days before harvesting.  

Bacterial Brown Rot:

It is a very serious disease of onions in storage. The infection occurs through the wounds. The rot begins at the neck of the bulbs which later gives a foul smell through the neck when squeezed. 

Control: 

Proper curing and rapid drying of the bulbs after harvesting is essential for controlling the disease. Affected bulbs should be discarded before storage. If rains occur during maturity, spraying of Streptocycline (0.02%) is recommended.