Abstract
Increasing the temperature and lengthening the acquisition access period improved the ability of Nephotettix cincticeps UHLER to acquire rice waika virus. Acquisition efficiency significantly increased up to a 24-hr access period and from 20 to 25°C. The maximum rate of transmission was obtained with a 48-hr acquisition access period at 30°C. Similarly, a greater efficiency of inoculation was obtained at higher temperature. In sequential transfer tests, temperature altered virus retention in the adults from only 1.5 days at 30°C to approximately 7 days at 15°C. When overwintering nymphs (late-instar) were examined, the maximum retention period increased to 3 weeks at 0-7°C. The rate of loss of infectivity by the vector showed nearly the same trend at alternating temperatures of 15 to 30 °C and 30 to 15°C at 12-hr transfer intervals as at 30°C constant temperature.
