Migration Analysis of Sogatella furcifera (Hemiptera: Delphacidae) in the Northeastern Hunan Province in June.

The Sogatella furcifera (Horváth) is a notorious and destructive insect pest, targeting >4 million hectares of rice cultivated in the Hunan Province. To understand the immigration dynamics, we collected S. furcifera light trap catches from 2006 to 2012 at Niangxiang, Linxiang, and Hanshou. We conducted a migration analysis to estimate the immigration source for the northeastern Hunan Province in June. Moreover, we dissected the ovaries of S. furcifera to classify population characteristics. We found that the first appearance of S. furcifera occurred from late April to early May, with June as the primary time for migrations into the northeastern Hunan Province. The majority of June ovaries caught in light traps were Grade I and Grade II, whereas those collected in paddy fields were Grade III and Grade IV, suggesting that the majority of S. furcifera immigrated into the northeastern Hunan Province. Our analysis points toward the northern and central Indo China Peninsula, the southern Hunan Province, the Guangxi Zhuang Autonomous Region Province, the Guangdong Province, and the Hainan Province as possible immigration sources of S. furcifera in June for the northeastern Hunan Province. We propose terrain, loss of forward flow, and wind shear as causes for the difference observed in light trap catches between Ningxiang, Linxiang, and Hanshou monitoring stations in the June of 2009. Thus, our results suggest that monitoring and forecasting of S. furcifera should be done with particular emphasis in June.