Real-time prediction system for migration of rice planthoppers Sogatella furcifera (Horvath) and Nilaparvata lugens (Stal) (Homoptera: Delphacidae)

Abstract

The white-backed planthopper, Sogatella furcifera, and the brown planthopper, Nilaparvata lugens, are pests of rice and migrate from south China to Japan in the rainy season of early summer. In order to achieve high-precision migration prediction, a real-time prediction system was developed. In this system, the latest meteorological data are supplied online to an advanced numerical weather prediction model, MM5. The model forecasts three-dimensional atmospheric fields at one-hour intervals. In these fields, a planthopper migration simulation model, GEARN, calculates movement of a number of modeled planthoppers and predicts their relative aerial density at three-hour intervals. The results are converted to maps and become available on the Internet. The maps of relative aerial density provide information about the timing and area of migrations over the next two days. During the main migration season in June and July 2003, the system achieved a prediction quality that was comparable to that of rainfall forecasts by the Japanese Meteorological Agency.

The 2008 overseas mass migration of the small brown planthopper, Laodelphax striatellus, and subsequent outbreak of rice stripe disease in western Japan

“…Prediction of these expected overseas migrations may be feasible and could be conducted by a modified version of the real-time prediction system for the brown planthopper, Nilaparvata lugens (Stål) and the white-backed planthopper, Sogatella furcifera (Horváth) (Otuka et al, 2005b). The current system predicts the migration of the two species mainly from southern China to Japan in the Bai-u rainy season.…”

“…Parameters of prediction calculations, such as the take-off date and take-off areas located in the possible source, are adapted to N. lugens. The temperature ceiling is also used in the prediction (Otuka et al, 2005b). This is a level of air temperature of 16.5°C, across which no simulated insects enter upper cooler air.…”

The Influence of Typhoon Khanun on the Return Migration of Nilaparvata lugens (Stål) in Eastern China

“…MM5 has been successfully used to simulate meteorological background in insect migration studies [14], [28], [48], [49]. Although typhoons are difficult to forecast due to their complicated structures and variable routes, MM5 can be used to simulate typhoon processes well based on reanalysis data [50]–[52].…”

“…Likely sources and landing area of migrating N. lugens were estimated by constructing backward/forward trajectories, based on the following assumptions: (i) the planthoppers are displaced downwind [20]–[23], [40], [45]; (ii) take-off takes place mostly at dusk and partly at dawn [20]–[23], [40], [45] ; (iii) the migrants are likely to land at any time; and (iv) the planthoppers cannot fly in an atmosphere of below 16.5°C [28], [40], [46]. The backward trajectories from light trap locations were calculated hourly during 0700 h to 0600 h, with initial 7 heights of 500, 750, 1000, 1250, 1500, 1750, and 2000 m above mean sea level.…”

“…Long-distance displacement is induced by a long-lasting warm and humid wind. A low-level jet sustained for a long time over a wide scale is the most favourable current for northward migrations [15], [22], [24]–[28]. Landing is often observed under windy, rainy, or even stormy weather when a frontal system passes over regardless of the time of the day.…”