SESAMUM :: MAJOR DISEASE :: PHYLLODY

Phyllody - Phytoplasma
Symptoms
The symptoms starts with vein clearing of leaves .The disease manifests itself mostly during flowering stage, when the floral parts are transformed into green leafy structures, which grow profusely. The flower is rendered sterile. The veins of phylloid structure are thick and prominent. The plant is stunted with reduced internodes and abnormal branching.

Phytoplasma -Symptoms 1	Phytoplasma - Symptoms 2

Pathogen
 It is caused by pleomorphic mycoplasma like bodies present in sieve tube of affected plants, now designated as a phytoplasmal disease.
Disease cycle
The pathogen has a wide host range and survives on alternate hosts like Brassica campestris var. toria,B. rapa, Cicer arietinum, Crotalaria sp., Trifolium sp., Arachis hypogaeawhich serve as source of inoculum.The disease is transmitted by jassid, Orosius albicinctus. Optimum acquisition period of vector is 3-4 days and inoculation feeding period is 30 minutes. The incubation period of the pathogen in leaf hoppers may be 15-63 days and 13-61 days in sesame. Nymphs are incapable of transmitting the phytoplasma. Vector population is more during summer and less during winter months.
Management

• Remove all the reservoir and weed hosts.
• Avoid growing sesamum near cotton, groundnut and grain legumes.
• Rogue out the infected plants periodically.
• Spray Monocrotophos or Dimethoate at 500ml/ha to control the jassids
• Soil treatment with Thirnet 10G @ 10 kg/ha or Phorate 10 G @ 11 kg/ha at the time of sowing.