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The aim of this study was to evaluate popcorn genotypes for resistance to the fall armyworm, Spodoptera frugiperda. The experiment used a completely randomized design with 30 replicates. The popcorn genotypes Aelton, Arzm 05 083, Beija-Flor, Colombiana, Composto Chico, Composto Gaúcha, Márcia, Mateus, Ufvm Barão Viçosa, Vanin, and Viviane were evaluated,along with the common maize variety Zapalote Chico. Newly hatched fall armyworm larvae were individually assessed with regard to biological development and consumption of food. The data were subjected to multivariate analyses of variance and genetic divergence among genotypes was evaluated through the clustering methods of Tocher based on generalized Mahalanobis distances and canonical variable analyses. Seven popcorn genotypes, namely, Aelton, Arzm 05 083, Composto Chico, Composto Gaúcha, Márcia, Mateus, and Viviane,were shown to form a cluster (cluster I) that had antibiosis as the mechanism of resistance to the pest. Cluster I genotypes and the Zapalote Chico genotype could be used for stacking genes for antibiosis and non-preference resistance. [ABSTRACT FROM AUTHOR]

Psyllids are one most widespread group of pests, causing severe damage on agricultural and forestry systems. The recently discover about occurrence of red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), in Brazil is, nowadays a serious problem in Eucalyptus forests, mainly in E. camaldulensis. The psyllid specific parasitic wasp Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) is the main biological control agent of this pest. Thus, the adequate monitoring of both species by efficient sampling method would facilitate a future decision making. Due to economic importance, this study aimed to evaluate G. brimblecombei and P. bliteus populations in Eucalyptus camaldulensis plantation, using yellow traps to determinate population fluctuation with weather interactions (temperature and rainfall). The study of the pest and parasitoid population (53 sampling dates) was carried out on E. camaldulensis plantations in 19ha area in Luíz Antônio municipality (SP, Brazil), with quarterly samplings, between January and June, 2005 (ten sampling dates). This research indicated that populations had an inversely proportional correlation subject according to the temperature. However, there is no correlation between both species with the rainfall in the evaluated period. [ABSTRACT FROM AUTHOR]