Adjustment of Planting Date to Reduce Rice Tungro Disease. V. D. Shukla, Research Scholar, Division of Plant Pathology, Central Rice Research Institute, Cuttack-753 006, India. A. Anjaneyulu, Virologist, Division of Plant Pathology, Central Rice Research Institute, Cuttack-753 006, India. Plant Dis. 65:409-411. Copyright 1981 American Phytopathological Society. DOI: 10.1094/PD-65-409.

The possibility of reducing the incidence of rice tungro disease by adjusting the date of planting was studied with cultivars Taichung (Native) 1, Pankaj, Ratna, and IR 20 in the field. Disease incidence was higher in Taichung (Native) 1 and Pankaj than in Ratna and IR 20. Disease incidence was very low in January, February, June, and July plantings and high in September, October, November, and December plantings. Vector populations (Nephotettix virescens) also were larger during later plantings. The number of leafhoppers (adults, nymphs, and eggs) was positively correlated with maximum and minimum temperatures, rainfall, relative humidity, maximum disease incidence, and rate of infection and was negatively correlated (only nymphs) with amount of sunshine.