Phytophagous stink bugs are major soybean pests, and knowledge of spatial distribution models of the pest in the crop is fundamental to establishing an appropriate sequential sampling plan, and thus, allowing the correct utilization of control strategies. This work aimed to study the spatial distribution of phytophagous stink bugs in soybean grown in different cropping systems and determine a sequential sampling plan. The experiment was conducted in Maracaju, MS, Brazil, during the agricultural year of 2012/2013. Soybean cultivars BRS 284 and SYN 1163 RR were placed in an experimental area comprising six fields (two soybean cultivars × three cropping systems). Sampling was performed weekly, using a beat cloth per plot and counting the number of stink bugs found, virtually throughout the soybean reproductive period. Concerning the statistical analyses, we used the dispersion indexes (variance‐to‐mean ratio, Morisita's index, exponent k of the negative binomial and Green's coefficient) and probabilistic methods of frequency adjustment (negative binomial and Poisson). Adult and nymph phytophagous stink bugs showed aggregate disposition in the field regardless of the cropping system, and their numbers were adjusted to the negative binomial probability distribution. There was no difference in the behaviour of adult and nymphs considering the tested cultivars. We elaborated a practical sequential sampling plan for phytophagous stink bug complexes, considering crops intended for the production of grains and seeds.

Sugere-se uma alteração no método de amostragem da cigarrinha-da-raiz para a cultura da cana-de-açúcar com o objetivo de aprimorar o controle da praga. O monitoramento convencional de Mahanarva fimbriolata pode subestimar o número de ovos da área, ocasionando ressurgência da praga. Neste sentido, um estudo foi realizado em Ponta Porã, MS, com o objetivo de alterar a proposta de amostragem da M. fimbriolata. O delineamento experimental composto por blocos casualizados, com dez tratamentos e quatro repetições. Os tratamentos testados foram: 1) Testemunha - não tratada, 2) Thiamethoxam 250WG - 250 g ha-1, 3) IBCB 425 - 5 x 10(9) con ha-1, 4) IBCB 425 - 10 x 10(9) con ha-1, 5) IBCB 425 - 15 x 10(9) con ha-1, 6) BIO 08 - 5 x 10(9) con ha-1, 7) BIO 08 - 10 x 10(9) con ha-1, 8) BIO 08 - 15 x 10(9) con ha-1, 9) IBCB 425 - 5 x 10(9) con ha-1 - aplicação granulada e 10) BIO 08 - 5 x 10(9) con ha-1 - aplicação granulada. As avaliações de eficiência dos tratamentos obtidas aos 15, 45, 75 e 105 dias após a aplicação (DAA). Aos 15 DAA os tratamentos com os isolados BIO 08 - aplicação granulada e IBCB 425 nas doses de 5 x 10(9) con ha-1 e 10 x 10(9) con ha-1 apresentaram eficiência de 73,33 e 70,66%, respectivamente. Não houve diferenças significativas entre os tratamentos com os inseticidas biológicos e químicos testados no experimento aos 75 e 105 DAA.

RESUMORelatou-se a ocorrência do besouro amarelo do eucalipto, Costalimaita ferruginea (Fabricius, 1801) (Coleoptera: Chrysomelidae), em novembro de 2009, em plantios clonais de Eucalyptus grandis x Eucalyptus urophylla, no município de Três Lagoas, Mato Grosso do Sul. Este é o primeiro registro dessa espécie em mudas clonais de eucalipto no Estado. No Brasil, Costalimaita ferruginea é considerada uma das principais pragas do eucalipto, devido a sua capacidade de causar injúrias, como o desfolhamento nas partes apicais da planta, promovendo perdas significativas no desenvolvimento e inviabilizando a comercialização da madeira e seus derivados. Palavras-chave: besouro amarelo do eucalipto; entomologia florestal; mudas clonais; insetos-praga. ABSTRACTThe occurrence of the eucalyptus yellow beetle Costalimaita ferruginea (Fabricius, 1801) (Coleoptera: Chrysomelidae) was repoted in November 2009 in clonal plantations of Eucalyptus grandis x Eucalyptus urophylla in Três Lagoas, Mato Grosso do Sul state. This is the first record of this species of eucalyptus seedlings in this state. In Brazil, Costalimaita ferruginea is considered a major pest of eucalyptus because of its ability to cause injuries such as the apical defoliation in parts of the plant, promoting significant losses in the development and inhibiting the marketing of wood and its derivatives. Keywords: eucalyptus yellow beetle; forest entomology; clone seedling; pest-insects.

Estimate efficiently of the whitefly population (Bemisia tuberculata Bondar) in cassava, to assist in decision making of pest control is one of the advantages of sequential sampling plans. Therefore, the objective of this study was to determine a sequential sampling plan according to two methods of pest management, using biological and/or chemical control. Samples were obtained in a commercial field of 2.500,00 m 2 , divided into 100 plots. The visualization method was used for sampling of the upper leaves by counting the number of adults. In total 15 samples were taken weekly from January to April 2012. The spatial distribution model which best fit to the behavior of B. tuberculata adults was the negative binomial distribution. Levels adapted for biological and chemical control were five and twenty adults per plant, respectively. Sampling plans resulted in two decisions for each proposed method. Thus, for population control the upper limit was defined as S 1 = 4.2056 + 2.1540n (biological) and S 1 = 20.219 + 10.4306n (chemical); and the lower limit where the pest control is not recommended was defined by S 0 = -4.2056 + 2.1540n (biological) and S 0 = -20.219 + 10.4306n (chemical). Sequential sampling estimated the maximum number of sample units necessary for decision-making of three samples with 1.34 adults for biological control and 3.85 sample units with 7.39 adult pests for chemical control.

RESUMOO objetivo desse trabalho foi avaliar a não preferência para a oviposição de Vatiga illudens (Drake, 1922) (Hemiptera: Tingidae) importante inseto com potencial de causar danos econômicos em cultivares de mandioca. Compararam-se as cultivares Kiriris, N-25, Fécula Branca, IAC 90, M Ecu 72 e IAC 576, essas com potencial produtivo para a região sul de Mato Grosso do Sul. Foram realizados ensaios de preferência para oviposição, com o teste sem chance de escolha, em condições de semi-campo. Um casal adulto de V. illudens foi liberado nas folhas de mandioca das respectivas cultivares. Permitiu-se a alimentação e oviposição desses insetos por 72 horas. Avaliou-se o número de ovos/fêmea/folha, o número de excrementos/casal/folha e o índice de preferência para oviposição. A cultivar M Ecu 72 revelou-se altamente resistente ao percevejo-de-renda. Esse estudo evidenciou que há mecanismos de resistência a V. illudens em cultivares de mandioca, o que justifica a realização de novos estudos sobre essas cultivares em programas de seleção, visando o controle dessa praga e identificação de tais mecanismos.Palavras-Chave: antixenose, insecta, resistência de plantas. ABSTRACTThe aim of this study was to evaluate the non-preference for oviposition Vatiga illudens (Drake, 1922) (Hemiptera: Tingidae) in cassava cultivars. The following cultivars were compared: Kiriris, N-25, Fécula Branca, IAC 90, M Ecu 72 and IAC 576, preference tests for oviposition were conducted, with a choice test in semi-field conditions. An adult double V. illudens was released in the leaves of cassava of their cultivars. Allowed to feeding and oviposition of these insects for 72 hours. We evaluated the number of eggs / female / leaf, the number of droppings / couple / sheet and the preference index for oviposition. The cultivar M Ecu 72 demonstrated to be highly resistant to cassava lace bug. This study showed that there are resistance mechanisms to V. illudens in cassava cultivars, which justifies the new studies on these cultivars in breeding programs, aiming to control this pest and identification of such mechanisms.

RESUMO:Vatiga illudens é uma praga de importância econô-mica para a cultura da mandioca. Conhecer a época de incidên-cia desse inseto em associação com fatores ambientais possibilita estratégias de controle. O objetivo deste trabalho foi determinar a flutuação populacional de V. illudens em cultivares de mandioca e verificar a correlação desses insetos com os fatores climáticos em Dourados, Mato Grosso do Sul. Foram avaliadas quatro cultivares de mandioca: Kiriris, N-25, IAC 90 e Fécula Branca. A avaliação populacional do percevejo-de-renda foi realizada durante 18 meses, observando 2 ciclos da cultura. Quinzenalmente, foram amostradas aleatoriamente quatro plantas centrais de cada parcela e cinco folhas do terço médio de cada planta, quantificando o número de ninfas e adultos por folha. Vinte meses após o plantio, foram colhidas duas fileiras centrais de mandioca de cada parcela e mensurada a produtividade em kg ha -1 . O delineamento experimental foi em blocos casualizados com quatro tratamentos e duas repetições. O pico populacional das ninfas e adultos para o primeiro ciclo da cultura ocorreu nos meses de março a maio. Para o segundo ciclo, esses índices populacionais aconteceram nos meses de janeiro a abril. O cultivar Kiriris apresentou maior número médio de ninfas e de adultos por folha de mandioca e o cultivar IAC 90, o menor número de insetos. Houve correlação negativa entre a população de insetos adultos e a produtividade de raízes. As temperaturas máximas, médias e mínimas afetaram a população de ninfas de V. illudens. Esses resultados são fundamentais para definir estratégias de manejo para controle do percevejo-de-renda. PALAVRAS-CHAVE: Vatiga illudens; Manihot esculenta; manejo integrado de pragas. ABSTRACT: Vatiga illudens is a pest of economic importancefor the cultivation of cassava. Knowing the time of incidence of this insect in combination with environmental factors enables control strategies. The objective of this study was to determine the population dynamics of V. illudens in cassava cultivars and the correlation of these insects for climatic factors in Dourados, Mato Grosso do Sul. Four cultivars of cassava were evaluated: Kiriris, N-25, IAC 90 and Fécula Branca. Population assessment of the lace bug was conducted over 18 months observing 2 crop cycles. Fortnightly, they were randomly sampled four central plants of each plot and five leaves from the middle third of each plant, quantifying the number of nymphs and adults per leaf. Twenty months after planting cassava, two central rows of each plot were harvested and measured productivity in kg ha -1 . The experimental design was randomized blocks with four treatments and two replications. The peak population of nymphs and adults for the first crop cycle occurred during the months from March to May. For the second cycle, these population indices happened in the months from January to April. Cultivar Kiriris showed the highest mean number of nymphs and adults per leaf cassava and cultivar IAC 90, the lowest number of insects. There was a neg...

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Dispersion patterns of Anthonomus grandis adults and damaged squares with their feeding punctures are important to enhance pest monitoring and control on cotton. In this research we performed probabilistic analyses of the distribution patterns of adults and squares with feeding punctures of A. grandis on two cotton genotypes, Bt and non-Bt near isogenic lines. We conducted the field experiment in two experimental areas; each area had 100 plots composed of seven rows, each seven metros long. Between Jan and May 2010, 16 samplings were made, in each, five plants were evaluated per plot by counting the adults and damaged squares. The dispersion indexes (ratio of the variance/mean, the Morisita index, and Exponent k of the Binomial Negative Distribution) and the theoretical distribution of frequencies (Poisson, Negative Binomial and Positive Binomial) were calculated. No differences between cotton genotypes were found. The spatial distribution of A. grandis adults fit the Negative Binominal (aggregate) and Positive Binominal (uniform) distributions, depending on the number of days after cotton emergence. The dispersion analyses of the feeding damaged squares on the Bt and conventional cotton revealed Poisson (random), Negative Binominal (aggregate) and Positive Binominal (uniform) distribution patterns in sequence during the crop cycle.