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The brown planthopper Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) is a major, regionally migratory pest of rice crops in Asia. Despite intensive studies, the seasonal pattern of migration in this species remains largely unknown, especially in northern China. Analysis of monitoring data of light trapping at Beihuang island in northern China showed that brown planthopper migrants could be found at the island in any month from July to October. However, the daily number of brown planthopper migrants varied considerably from day to day, month to month, and year to year. Most of migrants were caught from July to September, with fewer in October. Simulation of backward trajectories showed that there was temporal variation in the source areas of brown planthopper migrants trapped at Beihuang. A majority of migrants trapped at Beihuang in July came from south of Beihuang. In contrast, migrants caught in August and September could be from any direction around the island. Results suggested that the brown planthopper migrants likely traveled northward in July, and Multidirectionally in August and September in northern China. Some of brown planthopper in northeastern China could escape the 'Pied Piper effect' and migrate southward in September. [ABSTRACT FROM AUTHOR]

The white-backed planthopper, Sogatella furcifera (Horváth), is a destructive migratory pest in east and southeast Asia. Huge populations stemming from annual migrations by this insect have caused a series of devastating losses to rice production. There have been numerous early immigrations in five of the past 10 yr but few early immigrations in the others. The annual fluctuation in early immigration is evident, but the mechanism behind these annual fluctuations is unclear. This research aimed to determine the underlying causes for the annual fluctuations in early immigration. We used trajectory analysis to explore the source areas and investigated the meteorological conditions to determine the reason for the annual fluctuations. The results showed that 1) the source areas of S. furcifera are mainly located west of Guangdong and east of Guangxi; 2) the annual fluctuations of the immigrant population size is significantly correlated with the frequency of prevailing winds; and 3) early immigration is influenced by both winter and spring temperatures in the south central Indochina peninsula. These results indicated that an allopatric prediction and sustainable management of rice planthoppers would be difficult to implement within one country. International cooperation and information exchange about this pest between China and other countries in Southeast Asia should be implemented. [ABSTRACT FROM AUTHOR]

The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Heteroptera: Penatomidae), is a major pest of agricultural crops in the Mid-Atlantic States. Here we report the seasonal abundance, host preference, and injury potential of H. halys on tomato, bell pepper, green bean, sweet corn, eggplant, and okra in a small-scale, diversified vegetable farm setting. Life-stage densities, feeding injury, and crop phenology were monitored throughout the growing season in each crop. Populations consisted of both overwintered adults and F1 progeny and encompassed almost two generations over the growing season. H. halys preferred host plants with reproductive structures for feeding and was more abundant and capable to reproduce on vegetable crops that had extended periods of fruiting. Sweet corn, okra, and bell pepper had significant higher abundances of adults and nymphs compared with green bean, eggplant, and tomato. Results showed significant differences in the reproductive suitability of the host plants, as evident by the relative proportion of nymphal stages to adults. Eggplant, okra, and bell pepper were the most suitable host plants for reproduction and development, as evident by higher proportions of nymphs, with abundance trends indicating progressive development to adult eclosion. Crop loss potential due to H. halys feeding injury varied significantly among vegetable host plants. Sweet corn, okra, bell pepper, and tomato were very susceptible and experienced the highest injury rate per stink bug. The implications of these findings with respect to sampling and management of H. halys in vegetable production are discussed. [ABSTRACT FROM AUTHOR]

We report the results of a large-scale (six orchards) and long-term (5-yr) study on seasonal population fluctuations of fruit flies (Diptera Tephritidae) in mango (2005–2009) and cashew (2007–2009) orchards in the Borgou Department, Benin. During the five consecutive years of mango fruit fly monitoring, 25 tephritid species were captured including three species of Bactrocera, 11 of Ceratitis, and 11 of Dacus, which is represented by 2,138,150 specimens in mango orchards. We observed significant differences in Bactrocera dorsalis (Hendel) counts between "high" and "low" mango production years from 2005 to 2008 but not in Ceratitis cosyra (Walker) counts. The native species, C. cosyra, the most abundant species during the dry season, peaked beginning of May, while the exotic species, B. dorsalis, the most abundant species during the rainy season, peaked in June. Preliminary results underlined the role of nine species of wild hosts and seven species of cultivated ones around mango orchards that played an important role in maintaining B. dorsalis in this Sudan zone all year round. The presence of C. cosyra stretched over 9 mo. During the first 14 wk of tephritid monitoring on cashew orchards situated near mango orchards, most flies (62%) were captured in traps positioned in cashew orchards, showing the strong interest of an early fly control on cashew before the mango season. According to these results, in the Sudan zone, effective and compatible control methods as proposed by the IPM package validated by the West African Fruit Fly Initiative project against mango fruit flies are proposed for a large regional tephritid control program in same zones ofWest Africa. [ABSTRACT FROM AUTHOR]