• Initial symptoms of mottle streak disease appear around 45 days after sowing in funnel leaves as small sparse chlorotic specks.
• The virus-affected plants are stunted and pale green in colour.
• Later the specks coalesce leading to short streaks.
• Yellowing of plants in severe infection.
• Infected plants produce more of nodal branches and unproductive tillers.
• Failure of earhead emergence with sparse grains is noticed during initial and late infection.
• Vector for this disease is leaf hopper, Cicadulina

Identification of pathogen:

• Nucleo rhabdovirus or Potato Yellow Dwarf Virus is bacilliform, with one type of particle of about 380 x 75 nm. It is enveloped with a clear modal length of 178-224nm, 59-76 nm wide. Axial canal obvious; 8 nm in diameter

Management:

• Rogue out the affected plants
• Spray systemic insecticides Methyl dematon 500ml/ha. When noticing symptom and repeat twice if necessary at 20 days interval to control the vector

Source of hyphal segement: Plant Pathology by George N.Agrios Content Validator: Dr. T.Raguchandar, Professor (Plant Pathology), TNAU, Coimbatore -641003 Thanks to Dr.M.N.Budhar, Professor and Head, Regional Research Station, Paiyur- 65112