Rice yellow dwarf

Rice yellow dwarf: Mycoplasma Like organism

Symptoms:

  • The infected plants are stunted and have yellowish green to whitish green leaves. There is excessive tillering and leaves became soft and droop slightly.
  • Root growth is also reduced significantly.
  • Chlorosis occurs on the leaves occasionally even spreading to the leaf sheaths.
  • Streaks may also form parallel to the leaf veins.
  • If plants are infected early they usually die before maturity and even if they do survive no panicles are produced or only a small number of no grains.
  • Mode of spread: The Mycoplasma Like Organism (MLO) is transmitted by Nephotettix virescens and N. nigropictus with a latent period of 25-30 days. It survives on several grass weeds.

Management:

  • Deep ploughing during summer and burning of stubbles.
  • Rice varieties like IR62 and IR64 are resistant to the disease.
  • The management practices followed for Rice Tungro Disease(RTD) may be adopted for this disease also.
  • Avoiding early planted rice will prevent an increase in vector density and proportion of virus acquired vectors.
  • Planting fallow rice fields with non-vector hosts, ploughing fallow paddy fields and late-planting, synchronous planting or avoiding an overlap of early and late planted rice crops.

 

Source-

  • TamilNadu Agritech Portal