Stem canker

Description

     It is caused by fungi and reported on various Eucalyptus species and other forestry crops in plantations.


Pre-disposing Factors
1. The main causative factor is injury to the stem or branch of a tree. 
2. Suitable environmental factors help the pathogenic organisms to develop faster and cause damage to the trees.
Host Plants affected

    Some of the tree species generally affected by this diseases are Acacias, Eucalypts, Khair, Pinus, Sal, Sissoo Teak, Terminalia, etc.


Causal Organisms

     Some of the fungal organisms causing stem canker disease are species of Phoma, Phomopsis, Lasiodiplodia, etc

Symptoms

a) Slightly sunken, elongated areas measuring about 15-20 cm on the trunk either at the base or above ground, just after the south west monsoon.

b) The tissue beneath the depressed bark appears brown and apparently killed. As canker develops during the dry period (December to April) the bark show vertical splitting, which increases in length and width with age.

c) Generally at this time gummosis is observed in a few of the cankers. 

d) Typical wilting which results in death. 


Control measures

     Avoid injury to saplings and small trees during weeding and soil operations.  Long term control is to be attempted by appropriate site selection and breeding for resistant varieties against the stem canker disease.