Article

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

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Abstract

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.

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... The white-backed planthopper (WBPH) Sogatella furcifera (Hemiptera: Delphacidae) is an economically destructive rice pest distributed throughout Asia (Ma et al., 2017;Matsumura et al., 2014). As a migratory pest, S. furcifera has a great ability to spread, causing widespread damage to crops . ...
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. 1A case study is presented of the autumn migration of the brown planthopper, Nilaparvata lugens (Stål), in the area of Nanjing in the People's Republic of China. The study was made using a high frequency (8 mm wavelength) radar and a net suspended from a kytoon.2The observations confirmed that long-distance return migrations occur in China in mid and late September, with N.lugens being carried on the prevailing north-easterly wind towards the autumn infestation and overwintering areas of the species.3After mass take-off in the late afternoon or at dusk, the migrants flew for several hours during the evening, often in a dense layer which formed at heights between about 400 and 1000m above ground. These layers often had well-defined ceilings corresponding to an air temperature of about 16°C. The migration height was above the top of the surface temperature inversion, i.e. the migrants did not fly at the height of the warmest air.4The dense layer concentrations overflying the radar were backtracked to source areas up to 240 km away in the north-east of Jiangsu Province. Planthoppers observed emigrating from the Nanjing area would reach areas in south Anhui Province or north Jiangxi Province if they flew for 12 h.5There was a second period of mass take-off at dawn. Insect layers sometimes formed but did not last longer than 1–2h.6The present results were strikingly different from those previously observed in the dry season in the Philippines, where migratory flight durations were largely confined to periods of about 30min at dusk and dawn.7Our observations are discussed in relation to the equator-wards return migrations undertaken in autumn by other insect species, and the importance of these migrations for the maintenance of long-flying genotypes in the overwintering populations is considered.
Article
To evaluate the reproductive status of the female brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), an indirect sandwich enzyme-linked immunosorbent assay (ELISA) for monitoring vitellogenin (Vg) and vitellin (Vt) was developed by using monoclonal antibodies and polyclonal antiserum made specifically against BPH Vt. The ovarian development of BPH was divided into five stages according to ovariole development and morphological characteristics. Stages I–III, IV, and V represented the pre-oviposition, peak oviposition, and post-oviposition stages, respectively. Levels of Vt in the ovary and Vg/Vt in the whole female body during the five ovary stages appeared to relate well with the corresponding ovarian stages, suggesting that ovarian development can be evaluated by measuring ovarian Vt or whole body Vg/Vt in BPH. With this ELISA protocol, the reproductive status of macropterous BPH captured in rice fields during immigration, dwelling, and emigration was determined based on the levels of Vg/Vt in individual females. The females were mainly in stages I and II, as was confirmed by ovarian dissection. Therefore, this study presented an alternative method for evaluating the reproductive status of BPH in rice fields, which is more precise, convenient, and efficient than conventional techniques, such as dissection and classification of ovaries.
Study on the migration of whitebacked planthoppers, Sogatella furcifera (Horv ath)
  • National Coordinated Research Group of White-Backed Planthoppers
Low-level jet streams associated with spring aphid migration and current season spread of potato viruses in the U.S. northern Great Plains