Soybean root growth and yield in rotation with cover crops under chiseling and no-till

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Feeding substrates to black coconut bunch weevil, Homalinotus coriaceus (Gyllenhal) (Coleoptera: Curculionidae), rearing in laboratory

A broca do cacho do coqueiro, Homalinotus coriaceus (Gyllenhal), é uma praga limitante da produção de coco no Brasil, sendo que tanto as larvas como os adultos provocam a queda das flores femininas e dos frutos imaturos, pela interceptação do fluxo de seiva ou pela alimentação direta nas estruturas reprodutivas. em virtude da escassez de informações sobre sua biologia, realizou-se esse trabalho com o objetivo de desenvolver uma metodologia mais adequada para a criação da praga em laboratório. Foram utilizados os parâmetros biológicos para avaliação e comparação dos sistemas de criação estudados.Toletes de cana-de-açúcar foram utilizados como substrato para alimentação dos adultos coletados no campo e obtenção dos ovos. As larvas foram criadas em três substratos alimentares no Laboratório de Entomologia da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)-CPATC (Centro de Pesquisa Agropecuária dos Tabuleiros Costeiros), em Aracaju, SE. Os substratos alimentares estudados foram: o mesocarpo do coco, dieta para criação da broca dos citros e dieta para criação da broca do olho do coqueiro, sendo esta a que proporcionou o melhor desenvolvimento larval num menor tempo, com boa viabilidade, maior facilidade no preparo e manutenção.

Ocorrência de Migdolus fryanus (Coleoptera: Cerambycidae) em plantios de Pinus caribaea var. hondurensis

Larvas de Migdolus fryanus Westwood (Coleoptera: Cerambycidae) foram encontradas danificando raízes de mudas de P. caribaea var. hondurensis (Sénéel) Barr. & Golf. no Estado de São Paulo. Isso aumenta a importância dessa espécie, cujos danos, em espécies florestais, têm aumentado, principalmente, em plantios de eucalipto. Esse é o primeiro registro de M. fryanus em plantios de Pinus, e o referido inseto pode ser considerado uma nova praga dessa espécie florestal. Detalhes das características morfológicas e biológicas, danos e possíveis métodos de controle de M. fryanus são discutidos.

Ambrosia and bark beetles (Scolytidae : Coleoptera) in pine and eucalypt stands in southern Brazil

More than 95% of the reforested area in Brazil is covered by exotic Eucalyptus and Pinus plantations. Native Scolytidae, mostly ambrosia beetles, appear to be rapidly adapting to these exotic trees, and reports of economic damage are becoming frequent. The objectives of our research were to survey, characterize and compare the Scolytidae fauna present in a P. taeda and an E. grandis stand in Telemaco Borba, Parana state, Brazil. Beetles were caught in ethanol baited ESALQ-84 vane traps in weekly collections from July 1995 until July 1997. In all, 87 species were trapped, 62 in the pine and 75 in the eucalypt stand. The most abundant beetle species in the pines were Hypothenemus eruditus, Xyleborinus gracilis, Cryptocarenus sp. and Xylosandrus retusus, while the most frequent were H. eruditus, Cryptocarenus sp., H. obscurus, Ambrosiodmus obliquus, and X. gracilis. In the eucalypt stand, H. eruditus, X. retusus, H. obscurus, X. ferrugineus and Microcorthylus minimus were the most abundant species, and H. eruditus, H. obscurus and M. minimus were the most frequently trapped. The majority of the species, regardless of the forest community, were most active between August (end of winter) and October (mid-spring). Significantly more H. eruditus, X. gracilis, Cryptocarenus sp., Corthylus obliquus, Hypothenemus bolivianus, A. obliquus, Sampsonius dampfi and Xyleborus affinis were trapped in the pine stand, while X. retusus, H. obscurus, X. ferrugineus, Xyleborinus linearicollis, Corthylus sp, and Corthylus convexicauda were caught in higher numbers in the eucalypt stand. Approximately 50% of the species trapped were found in both communities. Morisita's similarity index indicates the composition of the two communities is very similar, suggesting that most of the beetles are polyphagous. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Can native vegetation recover after slash pine cultivation in the Brazilian Savanna?

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Antioxidant activity of Maytenus ilicifolia root bark

Maytenus ilicifolia is an important plant with potential on cancer treatment and has been largely used in Brazil and other countries. We have evaluated the crude ethanolic extract of M. ilicifolia as a potential antioxidant source using an assay based on the bleaching of the radical monocation 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(center dot+)) and by HOCl scavenger capacity. Trolox and uric acid were used as positive controls. The results indicated M. ilicifolia root bark as a great source of antioxidants based on its potential as scavenger of radicals. (c) 2006 Elsevier B.V. All rights reserved.

Bark and ambrosia beetle (Coleoptera : Scolytidae) responses to volatiles from aging loblolly pine billets

Many species of bark and ambrosia beetles use host volatiles as cues for breeding site location. In a study where the objectives were to identify the different volatiles released by Pinus taeda L. billets as they age, to determine the arrival sequence of scolytids (Colcoptera: Scolytidae), and to correlate volatile emission by the billets with beetle catches, 25 species of scolytids were trapped. Bark beetles were more attracted to the billets in the beginning of the period. whereas ambrosia beetles arrived later. Among the bark beetles, Dendroctonus terebrans (Olivier) was significantly more attracted during the Ist 3 wk after tree felling, Hylastes tenuis Eichhoff in the Ist 2 wk. Pityophtorus pulicarius (Zimmermann) in weeks 2 and 3, and Ips grandicollis (Eichhoff) was more attracted on weeks 3 and 4. Among the ambrosia beetles, Xyleborinus saxeseni (Ratzeburg) was more attracted to billets during weeks 4-6, whereas Xyleborus pubescens Zimmermann and Xyleborus californicus Wood were more attracted during week 6. The billets showed marked decline in attractiveness to all scolytids after 8 wk. Volatiles collected during the beetle trapping periods included 15 hydrocarbon monoterpenes, 18 oxygenated monoterpenes, 4-allylanisole, and ethanol. The hydrocarbon monoterpenes and 4-allylanisole decreased sharply over time, but oxygenated monoterpenes and ethanol increased up to weeks 4-6, after which they also decreased. Good correlations between certain billet volatiles and catches for some beetle species were obtained, but their biological significance could not be determined.

A method for plotting the complementary root locus using the root-locus (positive gain) rules

The root-locus method is a well-known and commonly used tool in control system analysis and design. It is an important topic in introductory undergraduate engineering control disciplines. Although complementary root locus (plant with negative gain) is not as common as root locus (plant with positive gain) and in many introductory textbooks for control systems is not presented, it has been shown a valuable tool in control system design. This paper shows that complementary root locus can be plotted using only the well-known construction rules to plot root locus. It can offer for the students a better comprehension on this subject. These results present a procedure to avoid problems that appear in root-locus plots for plants with the same number of poles and zeros.

Organophosphate resistance in the maize weevil Sitophilus zeamais: Magnitude and behavior

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeitos alelopáticos de extratos vegetais na germinação, colonização micorrízica e crescimento inicial de milho, soja e feijão

Restos vegetais e liteira podem interferir no desenvolvimento de plantas. Este trabalho objetivou avaliar os efeitos alelopáticos de extratos aquosos de Pinus sp., milheto (Pennisetum americanum (L.) Leeke) e mucuna (Stizolobium aterrimum Piper & Tracy) sobre a germinação, colonização micorrízica e crescimento inicial de milho (Zea mays L.), soja (Glycine max L.) e feijão (Phaseolus vulgaris L.). Os extratos foram elaborados utilizando folhas trituradas. O experimento in vitro empregou papel Germitest umedecido com extratos ou água destilada por sete dias. O experimento em casa de vegetação teve esquema fatorial 3 x 3 x 4, com quatro repetições: três espécies vegetais (soja, milho e feijão), três extratos aquosos (Pinus, milheto e mucuna) e quatro doses de extrato (0,0; 0,5; 1,0; e 2,0 kg L-1). O substrato foi Latossolo Vermelho coletado no município de Selvíria-MS, no bioma Cerrado. Após a semeadura, os vasos receberam, a cada cinco dias, por 45 dias, 50 mL dos extratos. Para a soja, extratos de mucuna e milheto diminuíram o comprimento do hipocótilo e da radícula e os de Pinus aumentaram esses comprimentos. em feijão, o extrato de Pinus diminuiu o comprimento do hipocótilo e da radícula, mas os extratos de mucuna e milheto aumentaram-no. O extrato do milheto reduziu a percentagem e a velocidade de germinação em feijão. Todos os extratos reduziram a colonização micorrízica e o número de esporos de fungos micorrízicos arbusculares em soja, milho e feijão.

On Complementary Root Locus of Biproper Transfer Functions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Periodontal tissue response to coverage of root cavities restored with resin materials: A histomorphometric study in dogs

Background: the purpose of this study was to histomorphometrically evaluate the response of periodontal tissues covering Class V resin restorations in dogs.Methods: After raising a mucoperiosteal flap, bony defects measuring 5 x 5 mm were created on the buccal aspect of the canines of five dogs followed by cavity preparations on the root surface measuring 3 x 3 x 1 mm. Before repositioning the flap to cover the bone defect, the cavities were restored with composite resin (CR) or resin-modified glass ionomer cement (RMGIC) or were left unrestored as control (C). The dogs were euthanized 90 days after surgery. Specimens comprising the tooth and periodontal tissues were removed, processed routinely, cut into longitudinal serial sections in the bucco-lingual direction, and stained with hematoxylin and eosin (H&E) or Masson's trichrome. The most central sections were selected for histomorphometric analysis.Results: Histomorphometric analysis revealed apical migration of epithelial tissue onto the restorative materials (RMGIC and CR). The C group presented significantly longer connective tissue attachment (P < 0.05) than the RMGIC and CR groups and significantly higher bone regeneration (P < 0.05) compared to the RMGIC group. Histologically, the cervical third (CT) of all groups had the most marked chronic inflammatory infiltrate.Conclusions: Within the limits of this study, it can be concluded that the restorative materials used exhibit biocompatibility; however, both materials interfered with the development of new bone and the connective tissue attachment process.

Multidisciplinary treatment approach for crown fracture and crown-root fracture - a case report

The increased incidence of traumatic injuries to anterior teeth is a consequence of leisure activities, where the most common injuries are crown fractures. Treatment of the dental trauma is complex and requires a comprehensive and accurate diagnostic and treatment plan. It is also important to consider the biological, functional, esthetic and economic aspects, as well as the patient's desire. The purpose of this article is to report a case that shows the multidisciplinary approach required to successfully manage the rehabilitation of a maxillary central incisor with a complex crown fracture and a maxillary lateral incisor, that at first presented an oblique crown-root fracture, and after the orthodontic extrusion, suffered a more apical new crown-root fracture.

Treatment of root perforation by intentional reimplantation: a case report

Intentional reimplantation is defined as a procedure in which an intentional tooth extraction is performed followed by reinsertion of the extracted tooth into its own alveolus. Int his paper, intentional reimplantation is described and discussed as a treatment approach to root canal instrument separation in conjunction with root perforation. An 8-year follow-up case report is presented. The reimplanted tooth is now a fixed bridge abutment. Although successful in this case, the intentional reimplantation procedure should be considered a treatment of last resort, that is, when another treatment option is not viable for the treatment of root perforation/instrument retrieval.