RESUMEN

Background: Gonipterus platensis Marelli, 1926 (Coleoptera: Curculionidae) is one of the main defoliating beetles in Eucalyptus plantations. Biological control with egg parasitoids is one of the main control strategies for this pest and a constant supply of fresh host eggs is required to rear the parasitoids. Polyandry can influence Gonipterus oviposition by increasing female fecundity and fertility; however, the high density of individuals in laboratory colonies can lead to male harassment, resulting in lower reproduction rate. The aim of this study was to measure the effects of monoandry and polyandry on the reproduction of G. platensis and the effects of male harassment on laboratory rearing conditions. Methods: Reproductive parameters were compared between three treatments: monoandry, where the female was allowed to mate daily with the same male; no choice polyandry, where the female was allowed to mate daily with a different male; and polyandry with choice, where the female was allowed to mate daily, but with a choice between five different males. Another experiment varying the density of males was conducted to evaluate the effect of male harassment. Results: Polyandry with choice resulted in the longest period of oviposition, highest fecundity and highest number of eggs per egg capsules when compared to monoandrous females. No negative effect related to male harassment in the laboratory, such as decreased fertility, fecundity, or number of eggs per egg capsule, was detected. Conclusion: Polyandry contributes to mass rearing as it increases fecundity and oviposition period on females and there is no evidence of male harassment on G. platensis.

Asunto(s)

RESUMEN

Insect pests introduced in eucalyptus plantations in Brazil are mostly of Australian origin, but native microorganisms have potential for their management. High quality biopesticide production based on entomopathogenic fungi depends on adequate technologies. The objective of this study was to evaluate Mycoharvester® equipment to harvest and separating particles to obtain pure Metarhizium anisopliae conidia to manage Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Hemiptera: Thaumastocoridae). The Mycoharvester® version 5b harvested and separated M. anisopliae spores. The pure conidia were suspended in Tween 80® (0.1%) and calibrated to the concentrations of 1 x 106, 107, 108 and 109 conidia/ml to evaluate the pathogenicity, lethal concentration 50 and 90 (LC50, LC90) and lethal time 50 and 90 (LT50, LT90) of this fungus to T. peregrinus. This equipment harvested 85% of the conidia from rice, with production of 4.8 ± 0.38 x 109 conidia/g dry mass of substrate + fungus. The water content of 6.36% of the single spore powder (pure conidia) separated by the Mycoharvester® was lower than that of the agglomerated product. The product harvested at the concentrations of 108 and 109 conidia/ml caused high mortality to T. peregrinus third instar nymphs and adults. The separation of conidia produced by solid-state fermentation with the Mycoharvester® is an important step toward optimizing the fungal production system of pure conidia, and to formulate biopesticides for insect pest management.

Asunto(s)

RESUMEN

The increasing production of biosolids in urban areas has been led to a search for alternative disposal avenues of this residue, which is rich in organic matter and nutrients. Agricultural land application of biosolids, motivated by its fertilizing power, is a widespread practice in many countries, but there are safety and regulatory concerns regarding the presence of pathogens in Class B biosolids. In addition, the scarcity of studies under tropical climate conditions raises questions that impede the agricultural use of this residue in some regions. The objective of this study was to evaluate the survival of thermotolerant coliforms over 12 months (52 weeks) after biosolids application on the surface of a Quartzipsamment neosol cultivated with Eucalyptus. Two different biosolids were studied: those generated by a biological treatment system with complete mixing aeration ponds followed by decantation ponds (Treatment A) and biosolids from a biological treatment system with conventional activated biosolids reactors (Treatment B), both delineated in randomized blocks with four replicates. After application on the forest soil, we estimated an average survival time of 54 weeks for thermotolerant coliforms present in Treatment A biosolids and 93 weeks in Treatment B biosolids. Thermotolerant coliforms persist much longer under tropical climate conditions in Brazil than in comparable studies under temperate climate conditions. This reaffirms the need to carry out studies covering the full range of moisture and temperature regimes in which biosolids are applied as fertilizer.

Asunto(s)

RESUMEN

The blue gum chalcid, Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae), causes galls on Eucalyptus spp. leaf midribs, petioles and stems. Biological aspects need to be studied to assist in developing management strategies and to maintain this insect in the laboratory to rear the parasitoid Selitrichodes neseri Kelly & La Salle (Hymenoptera: Eulophidae) that depends on having a supply of Eucalyptus seedlings infested by L. invasa. We evaluated the longevity and survival of L. invasa individual non reproductive females fed with six different diets (pure honey, 50% honey solution, pure honey plus eucalyptus leaves, eucalyptus leaves, distilled water, or no food) and seven different temperatures (10, 14, 18, 22, 26, 30 and 34 °C). Leptocybe invasa fed with 50% honey solution and reared at 14 or 18 °C showed the greatest longevity and survival.

RESUMEN

Growth functions with inflection points following a diphasic model, can be adjusted by two approaches using segmented regression or the sum of two functions. In both cases, there are two functions, one for each phase, with inflection and stability points. However, when they are summed, the result is a new function and the points of inflection and stability are different from those obtained from using each function individually. A method to determine these points in a diphasic logistics sum of functions is suggested and the results obtained from fitting the models to eucalyptus growth data showed a better fit of the logistic diphasic sum as compared with segmented regression and monophasic logistic models.

Asunto(s)

RESUMEN

Growth functions with inflection points following a diphasic model, can be adjusted by two approaches using segmented regression or the sum of two functions. In both cases, there are two functions, one for each phase, with inflection and stability points. However, when they are summed, the result is a new function and the points of inflection and stability are different from those obtained from using each function individually. A method to determine these points in a diphasic logistics sum of functions is suggested and the results obtained from fitting the models to eucalyptus growth data showed a better fit of the logistic diphasic sum as compared with segmented regression and monophasic logistic models.(AU)

Asunto(s)

RESUMEN

OBJETIVO: avaliar a utilidade da curva de regressão normal da gonadotrofina coriônica humana (hCG) no diagnóstico precoce de neoplasia trofoblástica gestacional pós-molar (NTG). MÉTODOS: estudo longitudinal, incluindo 105 pacientes com mola hidatiforme completa (MHC) acompanhadas no Centro de Doenças Trofoblásticas de Botucatu, entre 1998 e 2005. Os títulos da hCG sérica foram mensurados quinzenalmente em todas as pacientes. Curvas individuais de regressão da hCG das 105 pacientes foram estabelecidas. A comparação entre a curva de regressão normal estabelecida em nosso serviço com as curvas individuais da hCG foi usada no rastreamento e diagnóstico (platô/ascensão) de NTG. O número de semanas pós-esvaziamento quando a hCG excedeu o limite normal foi comparado com o número semanas em que a hCG apresentou platô/ascensão. RESULTADOS: das 105 pacientes com MHC, 80 apresentaram remissão espontânea (RE) e 25 desenvolveram NTG. Das 80 pacientes com RE, 7 (8,7 por cento) apresentaram, inicialmente, dosagem da hCG acima do normal, mas, no devido tempo, alcançaram a remissão. Todas as 25 pacientes com NTG apresentaram desvio da curva normal da hCG em 3,8±2,5 semanas e mostraram platô ou ascensão em 8,4±2,9 semanas (p<0,001). CONCLUSÕES: a curva de regressão normal da hCG pós-molar pode ser útil para diagnóstico de NTG.

PURPOSE: to evaluate the usefulness of the normal human chorionic gonadotropin (hCG) regression curve in the early diagnosis of post-molar trophoblastic neoplasia (GTN). METHODS: a longitudinal study including 105 patients with complete hydatidiform mole (CHM) followed up at the Botucatu Center of Trophoblastic Diseases from 1998 to 2005. Serial serum hCG titers were measured fortnightly in all patients. Individual curves of the 105 patients were built. Comparison between the normal regression curve established at our center with individual hCG curves was used to screen and diagnose (plateau/rise) GTN. The number of weeks postevacuation when hCG levels exceeded the normal limits was compared with the number of weeks when hCG reached plateau/rise. RESULTS: among the 105 patients with CHM, 80 reached spontaneous remission (SR) and 25 developed GTN. Among the 80 SR patients, 7 (8.7 percent) initially showed hCG concentrations above normal but eventually achieved remission. All the 25 GTN patients showed deviation from the normal hCG curve at 3.84±2.57 weeks and reached plateau or rise at 8.40±2.94 weeks (p<0.001). CONCLUSIONS: the normal regression curve of post-molar hCG is useful in the early diagnosis of GTN.

Asunto(s)

RESUMEN

Avaliou-se o crescimento e vigor das linhagens LE 96/17, LE 98/51, LE 98/53 e LE 98/56 de Lentinula edodes (Berk) Pegler em diferentes composições de meio de cultura. As linhagens foram provenientes da Micoteca do Módulo de Cogumelos da Faculdade de Ciências Agronômicas, Unesp, Campus de Botucatu. Os isolados foram obtidos por propagação vegetativa, pela transferência asséptica do micélio para o meio de cultura de extrato de serragem-dextrose-ágar. O crescimento e vigor do micélio foi fotografado diariamente com uma câmera digital, durante a incubação, até a colonização total da placa de Petri. As imagens foram analisadas pelo programa UTHSCSA ImageTool (freeware), versão 2.0, desenvolvido pela University of Texas Health Science Center, San Antonio, Texas. O modelo estatístico que melhor explicou a cinética de crescimento miceliano em área (mm2), das linhagens de cogumelos L. edodes, tem como componente determinístico a exponencial de uma função Gompertz. O vigor, avaliado através da cor do micélio (em escala de tons do cinza), revelou um comportamento similar entre as linhagens, com valor máximo entre o 4º e 5º dia e, em seguida apresentou declínio. Em meios de cultura mais enriquecidos, a velocidade de crescimento das linhagens de L. edodes foi menor e o vigor maior. O monitoramento digital permite uma avaliação objetiva do crescimento e vigor do L. edodes in vitro.

Asunto(s)

RESUMEN

Studies were carried out on the effects of coumarin, ferulic acid and naringenin on soybean seed germination and on the growth of seed-borne fungi at concentrations of 50 and 100 mg.L-1. The compounds showed good inhibition of seed germination, especially at 50 mg.L-1, but little fungistatic activity. Possible mechanisms of action are discussed