Diseases of fruit plantation medicinal and aromatic crops (2+1)

Stem bleeding

Causal organism: Thielaviopsis paradoxa (de Seyenes) Hohn.
Symptoms

• Both the young and old plants are affected but young palms are highly susceptible. Symptoms appear on the basal portions of the stem as small discolored depression during initial stages.
• Later the spots coalesce and cracks develop on the stem which eventually produces hollows upto varying depths along the infected portion.
• Crown of affected adult palms get reduced in size followed by reduction in yield. Finally a dark brown liquid oozes out from cracks.
Source of inoculum

• Primary source of inoculum: Dormant mycelia .
• Secondary source of inoculum: Air borne conidia.
Epidemiology

• More serious in kharif season and also more serious in case of poor drainage areas.
Management

• Improving the drainage may help in minimizing the disease incidence.
• Root feeding with proper chemical. Application of hot coal tar or Bordeaux paste is effective in reducing the disease.