Bacterial disease symptoms

Bacterial disease symptoms:-

1. Leaf spot with yellow halo:- Bacterial leaf spots caused by Pseudomonas show red-brown spots which can distort the infected leaves, whilst those caused by Xanthomonas are angular or circular in shape outlined with a yellow halo.

2. Fruit spot:- Fruit spot, symptom of plant disease, usually caused by fungi and bacteria. A spot is a definite, localized area. Spots frequently enlarge and merge to form a rot, a softening discoloration and often a disintegration of tissue.

3. Canker:- Cankers develop when the bacterial cells gain entry through wounds or leaf scars at the time of leaf fall. Cankers remain more or less dormant through summer, when tissues are resistant, and during autumn and winter when temperatures are low. In spring, the infections spread rapidly, killing the bark.

4. Crown gall:-

> Crown gall causes rough, woody, tumor-like galls to form on roots, trunks and occasionally branches of many different trees and shrubs.

> Galls can interrupt the flow of nutrients and water within the tree, reducing overall plant growth and vigor.

> Young plants with many galls, and plants with a gall completely encircling the main stem, are the most severely affected and can be killed by the disease.

> Mature trees often tolerate many galls with few negative effects.

> Plants with crown gall are more susceptible to drought stress, winter injury and secondary diseases that enter the plant through cracks in the gall.

5. Sheperd’s crook stem ends on woody plants:- Lesions are tan with dark borders and may have tiny black acervuli (fungal fruiting bodies) within them. As lesions grow together, stems can die, causing a “shepherd's crook” appearance of wilted stems. The anthracnose pathogen can spread from stem lesions to the crown in susceptible plants.