Cotton is an alternative host for Edessa meditabunda (Hemiptera: Pentatomidae), especially after the soybean harvest in surrounding areas, when large numbers of insects invade cotton fields and damage reproductive structures such as flowers and developing bolls. However, no studies on its occurrence and spatial distribution have been conducted in cotton. Therefore, this study was aimed to assess the temporal variation and spatial distribution of E. meditabunda in the alternative host plant, Gossypium hirsutum. The study was carried out in an area of 1.1 ha planted with cotton that was divided in 64 plots of 169 m 2 each, where entire cotton plants were examined weekly and E. meditabunda nymphs and adults were counted. Dispersion rates and theoretical frequency distributions were calculated and analyzed with significance level at 5%. Assessments were carried out from seedling emergence until the appearance of bolls, but E. meditabunda was present only during the reproductive stage of cotton plants. This study detected the dispersal of this stink bug from late-cycle soybean fields to cotton, indicating cotton's potential as an alternative host plant, providing shelter and food. Based on aggregation indices, the spatial distribution of nymphs and adults in cotton was aggregated at the beginning of the infestation, but tended toward randomness as bolls reached maturity. The occurrence of E. meditabunda in cotton was best described by the Poisson distribution with significance level at 5%.

This study was aimed at examining the composition of insects and fluctuations in their populations in Avena sativa in southern Mato Grosso do Sul. The study was carried out at the experimental farm of the Federal University of Grande Dourados (FAECA) in Dourados, Mato Grosso do Sul, in 2014 and 2015, in an area of three hectares divided into 80 plots of 169 m2 each. The assessments were carried out weekly by sampling the area within a 0.25-m2 metal frame, totaling ten evaluations. Within the frame, ten plants were examined for aphids and all plants were inspected for other insects. Based on the faunistic analysis (abundance, constancy, frequency, and dominance), eight species were observed during the two years of study. The most frequent, abundant, dominant, and recurring species were Rhopalosiphum padi, Spodoptera frugiperda and dipterans of the family Syrphidae (hoverfly). The population of R. padi increased until approximately the 40th day after emergence (DAE), when the highest abundance of hoverflies was also observed. After that, the population of R. padi decreased. The aphid R. padi was the main insect observed in A. sativa during the two years of study but were naturally controlled by hoverflies; therefore, chemical intervention was not needed.