Bud rot is a fatal disease of the coconut palm, characterized by the rotting of the terminal bud and the surrounding tissues. It affects the palms of all ages, but young palms are found to be most vulnerable. The disease is caused by the fungus Phytophthora palmivora and the incidence is found to be severe during monsoon when the relative humidity is high. With the onset of dry weather, the infection becomes less severe and the fungus remains dormant in the leaf base.
Symptoms of damage:
- The first visible symptom is the withering of the spindle marked with pale color.
- The spear leaf or spindle turns brown and bends down.
- On dissecting such affected spindles, rotting of internal tissues could be observed, the tissues show pale pink color with a brown border.
- The affected spindle can be easily pulled out at this stage.
- A foul smell is emitted by the rotting tissue.
- The palm ultimately succumbs to the diseases with the death of the spindle.
- As a prophylactic measure, adjacent healthy palms should be sprayed with 1 percent Bordeaux mixture or with any other copper-based fungicide like Copper Oxy Chloride@ 2g per liter of water. A pre and post-monsoon sprays of the above fungicide are recommended for the management of the disease. Maintaining proper drainage also reduces disease incidence.
- Spraying the palms with Dimethomorph @ 1 g/liter of water.
- Spraying the palms with Metalaxyl 35 EC @ 2 g/liter of water.