Pomegranate Diseases

Bacterial leaf and fruit spot

Disease symptoms:

• Appearance of one to several small water soaked, dark colored irregular spots on leaves resulting in premature defoliation under severe cases.
• The pathogen also infects stem and branches causing girdling and cracking symptoms.
• Spots on fruits were dark brown irregular slightly raised with oily appearance, which split open with L-shaped cracks under severe cases.

Survival and spread:

• Primary source of inoculum is Infected cuttings
• Secondary source of inoculum spreads through Wind splashed rains.

Favourable conditions:

• The increase in day temperature (38.6°C) and afternoon relative humidity of 30.4% along with cloudy weather and intermittent rainfall favored the disease initiation and further spread of the disease.

Leaf and fruit spot

Disease symptoms:

• Leaf spots are minute, brown with yellow halo.
• Spots are scattered, circular or irregular and become dark brown with age.
• Spots on lower side are sunken with clusters of spore bearing structures hence greyish in colour.
• Minute, circular, black spots appear on sepals of the flower.
• Fruit spots are black, minute and circular on rind.
• When grow old, become large, irregularly circular and depressed presenting an ugly look to the fruits.

Favourable conditions:

• Optimum temperature is 25-32°C with night temperatures above 16°C, and a relative humidity of 90-95%.

Survival and spread:

• Primary spread : Diseased plant debris
• Secondary spread : Wind borne conidia

Anthracnose

Disease Symptoms:

• Small, regular to irregular black spots on leaves, calyx region and fruits which turn later on as dark brown depressed spots.
• Infected leaves turn yellow and drop off.

Survival and spread:

• Primary source of inoculum: Infected leaves
• Secondary source of inoculum: windborne conidia.

Favourable conditions:

• The disease is severe during August-September when there is high humidity, and the temperature  between 20-27ºC.

Fusarium wilt

Disease symptoms:

• Affected plants show yellowing of leaves in some twigs or branches, followed by drooping and drying of leaves.
• The entire tree dies in few months or a year.
• When affected tree is cut open lengthwise or cross-section dark grayish-brown discolouration of wood is seen.