Mosca-Negra-dos-Citros: Características Gerais, Bioecologia e Métodos de Controle dessa Importante Praga Quarentenária da Citricultura Brasileira

Citrus blackfly, Aleurocanthus woglumi Ashby, is a serious pest of citrus culture and other economically important fruit crops. It is a present quarantine pest or A2 maximum alert restricting trades with other regions free of its presence. Since the frst occurrence of the citrus blackfly in Belem in 2001 its dissemination was quickly to other States and regions of citrus production in Brazil. As an exotic pest, basic knowledge is scarce in order to establish the appropriate management to the insect in Brazil. Thus, the aim of the present study was to provide information about important aspects of A. woglumi, such as: history and geographical distribution, bioecology, host plants, appropriate control methods, among others, in order to provide subsidies for futures researches about the citrus blackfly in Brazil.

Paleocanais no megaleque do rio Taquari: mapeamento e signifcado geomorfológico

This paper presents the results of the frst systematic mapping of the paleochannel network on the Taquari megafan (Pantanal, Brazil). We used remote sensing data collected by the ASTER sensor, which captures images with 15 m square pixels. A total of 34 scenes, acquired from 2001-2006, were used in the analysis. These data were processed using a decorrelation stretch technique in order to obtain a better visual identifcation of the paleochannels. The mapping procedure began with the overlay of a 1:50.000 IBGE articulation, in order to systematize the extraction of features and to reduce the subjectivity inherent to visual analysis methods. We mapped a total of 33,205 km of paleochannels. The density of these features is related to the relative ages of distinct geomorphological compartments, known as depositional lobes. The mapped features preserve avulsion events that occurred on the megafan. The results suggest that low-magnitude avulsions occur more frequently than larger events.