Soybean bugs are major crop pests that cause significant reduction in harvest yield and influence grain quality. The aim of this study was to verify the spatial distribution of Euschistus heros (F.) (Hemiptera: Pentatomidae) in conventional and transgenic soybean cultivars. The experiment was conducted during the 2010-2011 crop season in UNESP/FCAV, Jaboticabal, SP, Brazil, in two fields of 10,000-m(2) area that were subdivided into 100 plots (10 m × 10 m). The cultivars sown were M 7908 RR and its isoline M-SOY 8001. The number of the first to fifth instars and the number of adults were determined. To evaluate insect dispersion in the area, the following indices were used: variance/mean ratio, Morisita index, Green coefficient, and the k exponent of the negative binomial distribution. To study probabilistic models to describe the spatial distribution of the insects, the adjustments of the Poisson and negative binomial distributions were tested. The first to third instars showed aggregated spatial distribution, whereas the fourth and fifth instars, and adults, isolated or grouped, showed variation in the arrangement, ranging from moderately aggregated to randomly dispersed. During the adjustment of probability distributions, the negative binomial distribution model showed adjustment for the first to third instars, fourth and fifth instars, adults, and fourth and fifth instars plus adults.

We study the zero temperature ground state of a two-dimensional atomic Fermi gas with chemical potential and population imbalance in the mean-field approximation. All calculations are performed in terms of the two-body binding energy ǫB, whose variation allows to investigate the evolution from the BEC to the BCS regimes. By means of analytical and exact expressions we show that, similarly to what is found in three dimensions, at fixed chemical potentials, BCS is the ground state until the critical imbalance hc after which there is a first-order phase transition to the normal state. We find that hc, the Chandrasekhar-Clogston limit of superfluidity, has the same value as in three dimensional systems. We show that for a fixed ratio ǫB/ǫF , where ǫF is the two-dimensional Fermi energy, as the density imbalance m is increased from zero, the ground state evolves from BCS to phase separation to the normal state. At the critical imbalance mc phase separation is not supported and the normal phase is energetically preferable. The BCS-BEC crossover is discussed in balanced and imbalanced configurations. Possible pictures of what may be found experimentally in these systems are also shown. We also investigate the necessary conditions for the existence of bound states in the balanced and imbalanced normal phase.

The neotropical stink bug Euschistus heros is the predominant and most important insect pest affecting soybean cultivation. Knowledge of the spatial pattern of the pest in an area is critical to understanding its behavior. The objective of this work was to study the spatial distribution of E. heros in transgenic soybean cultivars of different maturing cycles. The experiments were conducted in the seasons 2013/14 and 2014/15 in FCAV/UNESP, Jaboticabal, SP. Three fields were selected, and each was marked an area of 8.000 m 2 (0.8 ha), with each area divided into 80 portions of 100 m 2 (10 m x 10 m). The transgenic soybean cultivars of different maturing cycles were: SYN 1365 RR (early), M 7908 RR (average), and BRS Valiosa RR (late). Samples were taken weekly using a beat sheet, registering the number of nymphs and adults of E. heros. To study the dispersion of E. heros, the following indices were used: variance/ mean ratio, Morisita index, Green coefficient, and the exponent k of the negative binomial distribution. For studies of special distribution models of E. heros, adjustments of Poisson distribution and negative binomial distribution were tested. The spatial distribution of nymphs and adults was aggregated for all the cultivars studied, indicating that cultivars did not alter the distribution behavior of E. heros. Key words: Glycine max (L.). Behavioral ecology. Dispersion. Negative binomial distribution. Neotropical brown stink bug. ResumoO percevejo-marrom-da-soja Euschistus heros, destaca-se como o inseto-praga predominante e mais importante na cultura. O conhecimento do padrão espacial da praga na área é fundamental para o entendimento do seu comportamento. O objetivo do presente trabalho foi estudar a distribuição espacial de E. heros em cultivares de soja transgênica de diferentes ciclos de desenvolvimento.

INTRODUÇÃOO algodoeiro (Gossypium hirsutum L.) é uma planta perene, que pode permanecer por vários anos em ambientes favoráveis. A natureza perene do algodoeiro permite sua rebrota após a colheita, produzindo estruturas adequadas à reprodução e manutenção do bicudo-do-algodoeiro (Anthonomus grandis Boheman, 1843) (Coleoptera: Curculionidae), na área de cultivo, após três ou quatro semanas (Greenberg et A destruição dos restos culturais do algodoeiro, ao final do ciclo de cultivo, é uma estratégia fundamental no manejo fitossanitário da cultura, já que a sua rebrota, no período de entressafra, pode oferecer sítios de alimentação e de oviposição para pragas como o bicudo-do-algodoeiro. Este trabalho objetivou avaliar a capacidade de rebrota de cultivares de algodoeiro, bem como sua infestação por Anthonomus grandis. Utilizou-se o delineamento experimental em blocos casualizados, em esquema fatorial 3 x 2, com três cultivares (FM 910, DeltaOPAL e NuOPAL), duas alturas de roçagem (10 cm e 20 cm) e quatro repetições. Foram realizadas avaliações semanais da porcentagem de rebrota das plantas nas duas alturas de roçagem, número de botões florais, porcentagem de botões florais infestados pelo bicudo e número de adultos por rebrota. Plantas roçadas a 10 cm de altura apresentaram menor capacidade de brotação e, consequentemente, de emissão de botões florais, reduzindo a densidade populacional do bicudo na área, enquanto plantas roçadas a 20 cm apresentaram altos índices de rebrota, aos sete dias após a roçada. A cultivar FM 910 apresentou o maior número de plantas rebrotadas e, para a cultivar DeltaOPAL, registrou-se o maior número de botões florais e adultos por planta, bem como a maior porcentagem de botões com danos causados pelo bicudo-do-algodoeiro. PALAVRAS-CHAVE: Gossypium hirsutum; bicudo-doalgodoeiro; soqueira de algodão. ABSTRACT RESUMO Infestation of Anthonomus grandis (Coleoptera:Curculionidae) on re-sprout of cotton plantsThe destruction of cotton crop residues at the end of the crop cycle is a key strategy for the phytosanitary crop management, since its off-season re-sprout can provide sites for feeding and oviposition of pests such as the boll weevil. This study aimed to evaluate the re-sprout capacity of cotton cultivars, as well as their infestation by Anthonomus grandis. A randomized blocks design, in a 3 x 2 factorial arrangement, with three cultivars (FM 910, DeltaOPAL and NuOPAL), two mowing heights (10 cm and 20 cm) and four replications, was used. Weekly evaluations were carried out for measuring the percentage of plant re-sprout for both mowing heights, percentage of flower buds infested by the boll weevil and number of adults per re-sprout. Plants mowed at 10 cm presented a lower sprout capacity and consequently less flower buds, reducing the boll weevil population density in the area, while plants mowed at 20 cm showed high re-sprouts rates, seven days after mowing. The FM 910 cultivar had the highest number of re-sprout plants, while the DeltaOPAL cultivar showed the highest number of flower bu...

The feeding and oviposition behavior of boll weevil in new cotton cultivars is essential for an adequate management. The objective of this study was to evaluate the vertical distribution of squares punctured for feeding and oviposition of the pest in the cultivars NuOPAL, DeltaOPAL, FMT-701, FMX-910 and FMX-993, and record the most and least preferred times of feeding and oviposition. The number of squares used for boll weevil feeding and oviposition were evaluated weekly in three parts of plant canopy. It was observed that, regardless the cultivar, A. grandis preferred to lay eggs in squares located in the upper part and feed on squares in the middle and upper parts. The boll weevil preferred to feed on cultivar FMT-701 in the beginning of the period of cotton flowering and fruiting, and the cultivars NuOPAL, DeltaOPAL, FMX-910 and FMX-993 throughout the whole period of flowering and fruiting. A. grandis preferred to lay eggs on cultivars NuOPAL, FMT-701 and FMX-993 at the beginning and end of flowering and fruiting of plants, while the cultivars DeltaOPAL and FMX-910 are used for oviposition throughout the period of flowering and fruiting.