Abstract:Low level jet (LLJ) is an ideal passageway for the long\|distance migrations of Nilaparvata lugens (Stl)′s populations. In order to explore the effect of LLJ on BPH′s migrations northward, we have conducted a synthetic analysis of the Chinese BPH′s lighting catches in 2007 and done some case studies in combination with the respective weather data. Our results indicate: (1) the LLJ as a large\|scale weather system in Eastern Asia, played an important role in the great migrations northward of Chinese BPH′s populations in 2007 linking the pest sources and the destination of the migrant populations; (2) the tempo\|spatial distribution and strength change of LLJ had a significant impact on the landing times, landing scopes, landing heads of BPH′s populations, and the selection of the main landing regions; (3) the prediction of that the brown planthoppers immigrated into the main landing regions carried by LLJ by a trajectory\|backward approach is consistent with LLJ dynamic explanation; (4) the downstream of LLJ played a key role in the distribution of the BPH′s landing areas.