Effect of Temperature on Rice Stripe Virus Infection, Transmission Efficiency, and the Development Period in Laodelphax striatellus

The small brown planthopper, Laodelphax striatellus, is a major pest and the primary vector of the rice stripe virus, a harmful pathogen that significantly affects rice production across East Asia. This study aims to investigate the effects of different temperatures (24°C, 27°C, and 30°C) on the developmental period, rice stripe virus infection rates, and virus transmission efficiency of small brown planthopper at various developmental stages. Higher temperatures significantly shortened the developmental period of small brown planthopper. The time from egg to adult was approximately 5 days shorter at 30°C than at 24°C. The rice stripe virus infection rate gradually increased, peaking after the third instar nymph, with no significant differences observed between 24°C and 27°C. However, at 30°C, the infection rates in the second to fifth instar nymphs were lower compared to those at the other temperatures. Tissue-specific analyses indicated that the thorax, midgut, and ovary serve as primary loci for rice stripe virus proliferation. Temperature significantly affects small brown planthopper development and rice stripe virus epidemiology. Accelerated development rates at higher temperatures may result in increased population turnover, whereas reduced rice stripe virus transmission efficiency under these conditions could alter viral spread dynamics. These findings are vital for developing pest management strategies that consider temperature fluctuations and climate change.