Plant Spacing to Reduce Rice Tungro Incidence. 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. 65:584-586. Copyright 1981 American Phytopathological Society. DOI: 10.1094/PD-65-584.

Rice cultivars Taichung Native 1 (TN1), Pankaj, and Ratna were planted at spacings of 10 × 10, 10 × 15, 15 × 15, 15 × 20, and 20 × 20 cm. Disease incidence generally increased with increased in plant spacing. Differences in disease incidence among the spacings were more pronounced in the tolerant cultivar Ratna than in the susceptible and highly susceptible cultivars Pankaj and TN1, respectively. Grain yields were significantly higher in the 10 × 10 and 10 × 15 cm spacings than in the wider spacings for cultivars Pankaj and Ratna, but differences in yields were not significant among spacings in TN1. The adult leafhopper population (Nephotettix virescens) was fairly uniform in all spacings, but the nymph population was slightly higher in the closer spacings.