The Influence of the Topography of the Ailao Mountains on Congregated Landings of Airborne Sogatella furcifera (Hemiptera: Delphacidae) Populations

Abstract

The Sogatella furcifera (Horváth) is an important migrating rice pest whose outbreak may be caused by large-scale congregated landings. Hitherto, the meteorological factors that influence congregated landings were thought to be rainfall and downdraft. However, for migratory insects on a plateau, low temperature may be another key factor leading to congregated landings. However, no reports have been published. Therefore, this paper evaluates the reason for a large-scale congregated landing in the mountainous area in Yuanjiang via light trap monitoring. The meteorological backgrounds during light catch peaks were analyzed using the numeric simulation method. The results were as follows: 1) from May 7th to May 9th, 2012, the congregated landing of S. furcifera was caused by precipitation; 2) the congregated landing of S. furcifera on May 10th, 2012, was a result of low temperatures in the mountainous region. The driving airflow of S. furcifera climbed along the mountain terrain, which led to a decrease in temperature with the rise of the mountain terrain. Low temperature created physiological changes in S. furcifera, forcing S. furcifera to a lower flight altitude and eventually to a congregated landing; and 3) in the statistical analysis on 39 peak periods from 2010 to 2016 in the early spring, 20 peaks were caused by precipitation, and 19 peaks were caused by a low temperature barrier. Therefore, this study provided evidence of a plateau-migrating S. furcifera population congregated landing caused by low temperature.

Identifying ImmigratingSogatella furcifera(Hemiptera: Delphacidae) Using Field Cages: A Case Study in the Yuanjiang (Red River) Valley of Yunnan, China

“…The authors believe that the continuous migration observed in the current study may well represent the short-range migration form of S. furcifera in Yunnan under normal circumstances, as reported by other research (Hu 2013; Zheng et al 2014b; Li et al 2017a,b; Wang et al 2017; Wu et al 2017). This migration pattern is remarkably different from some previously reported cases in a few localities in Yunnan and South to East China, which were characterized by a large abrupt immigration of macropterous adults in a very short period of time (e.g., overnight) and from a very distant source (Shen et al 2011, 2016; Jiang et al 2012; Wu et al 2012; Zhao et al 2014; Bi et al 2017; Hu et al 2017). Such migration events in South and East China are facilitated by flat terrain as mentioned previously; but in Yunnan, they are probably caused by occasional weather events or special terrain features (which may promote landings).…”

“…The white-backed planthopper, Sogatella furcifera (Horváth), is a serious pest on Asian cultivated rice, Oryza sativa L. in South China and North Indochina (Catindig et al 2009; Cheng 2009, 2015). Migratory behavior, high fecundity, and exponential population growth are the main causes of disastrous yield loss as well as the difficulty in performing accurate forecast and effective prevention (Gui et al 2008; Cheng 2009; Hu et al 2014, 2017).…”

“…It is generally accepted that, in South China, the northward migration of S. furcifera is mainly driven by monsoon currents (monsoons from the Pacific and Indian oceans) with the following two forms: 1) long-range migration in East and South China where the terrain is flat with less hills (Zhai 2011, Zhao et al 2014) and 2) short-range migration from the south to adjacent north in West China where the terrain is very complex, featuring high-altitude mountain ranges and deep valleys (Hu 2013; Zhao et al 2014; Wu et al 2017, 2018).…”

“…When a local or overwintering population forms an early outbreak source, management of winter paddies, and ratooning rice should be prioritized, followed by regular monitoring and management measures. When the first and heaviest outbreak sources usually come from immigrants, regular monitoring and preimmigration management should be taken equally (Hu 2013; Hu et al 2014, 2017). Hence, accurate identification of outbreak sources and migration patterns of S. furcifera is crucial to formulate highly efficient prevention and control strategies.…”

Temporary inhibition of positive phototaxis in emigratory population of Nilaparvata lugens by mark-release-recapture

“…This paddy was moderately fertile and was maintained with routine cultural practices, and no pesticide was used during the rice-growing season. Systematic field investigation of BPH population was performed once every 3 d by a plant-shaking method [11, 21].…”