994 resultados para BIOLOGICAL IDENTIFICATIONS


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This study aimed at evaluating the biological characteristics and the capacity of parasitism of a Trichogramma pretiosum Riley, 1869 (Hymenoptera, Trichogrammatidae) strain (T. pretiosum RV) collected in Rio Verde County, State of Goiás, Brazil. The study was carried out on eggs of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera, Noctuidae) and conducted under controlled environmental conditions at different constant temperatures. The biological parameters determined were: developmental time (egg-adult; days); emergence (%); sex ratio; number of progeny/egg; number of generation/year; thermal constant (K); temperature threshold (Tb); daily number of parasitized eggs; cumulative parasitism (%); total number of eggs parasitized by T. pretiosum; and female longevity. To study the T. pretiosum parasitism capacity, 20 S. frugiperda eggs (< 24 h old) were placed into 8.0 cm x 2.0 cm glass vials containing one female (< 24 h old) each. Trials were carried out in a completely randomized experimental design, with 20 replications at each temperature. The environmental chambers (BOD type) were set at 18ºC, 20ºC, 22ºC, 25ºC, 28ºC and 32ºC ± 1ºC, 70 ±10% relative humidity, and 14/10 h (L:D) photoperiod. The eggs of S. frugiperda were replaced daily until parasitoid death. Results have shown an inverse correlation between developmental time and temperature, with statistically significant differences among means, except at 25ºC and 28ºC (10 days). Parasitoid emergence (%) was also influenced by temperature. The lowest percent emergence was observed at 32ºC, and the highest ones at 18ºC and 20ºC temperatures. The temperature did not affect T. pretiosum sex ratio and number of parasitoids per egg, thus allowing changes in the temperature to control insect mass production in the laboratory to meet the needs for field releases.

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Will the Convention on Biological Diversity put an end to biological control? Under the Convention on Biological Diversity countries have sovereign rights over their genetic resources. Agreements governing the access to these resources and the sharing of the benefits arising from their use need to be established between involved parties. This also applies to species collected for potential use in biological control. Recent applications of access and benefit sharing principles have already made it difficult or impossible to collect and export natural enemies for biological control research in several countries. If such an approach is widely applied it would impede this very successful and environmentally safe pest management method based on the use of biological diversity. The International Organization for Biological Control of Noxious Animals and Plants has, therefore, created the "Commission on Biological Control and Access and Benefit Sharing". This commission is carrying out national and international activities to make clear how a benefit sharing regime might seriously frustrate the future of biological control. In addition, the IOBC Commission members published information on current regulations and perceptions concerning exploration for natural enemies and drafted some 30 case studies selected to illustrate a variety of points relevant to access and benefit sharing. In this article, we summarize our concern about the effects of access and benefit sharing systems on the future of biological control.

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Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae). Studies on Ceratitis capitata, a world fruit pest, can aid the implementation of control programs by determining the plants with higher vulnerability to attacks and plants able to sustain their population in areas of fly distribution. The objective of the present study was to evaluate the influence of eight tropical fruits on the following biological and behavioral parameters of C. capitata: emergence percentage, life cycle duration, adult size, egg production, longevity, fecundity, egg viability, and oviposition acceptance. The fruits tested were: acerola (Malpighia glabra L.), cashew (Anacardium occidentale L.), star fruit (Averrhoa carambola L.), guava (Psidium guajava L.), soursop (Annona muricata L.), yellow mombin (Spondias mombin L.), Malay apple (Syzygium malaccense L.), and umbu (Spondias tuberosa L.). The biological parameters were obtained by rearing the recently hatched larvae on each of the fruit kinds. Acceptance of fruits for oviposition experiment was assessed using no-choice tests, as couples were exposed to two pieces of the same fruit. The best performances were obtained with guava, soursop, and star fruit. Larvae reared on cashew and acerola fruits had regular performances. No adults emerged from yellow mombin, Malay apple, or umbu. Fruit species did not affect adult longevity, female fecundity, or egg viability. Guava, soursop, and acerola were preferred for oviposition, followed by star fruit, Malay apple, cashew, and yellow mombin. Oviposition did not occur on umbu. In general, fruits with better larval development were also more accepted for oviposition.

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Cell surface receptors bind ligands expressed on other cells (in trans) in order to communicate with neighboring cells. However, an increasing number of cell surface receptors are found to also interact with ligands expressed on the same cell (in cis). These observations raise questions regarding the biological role of such cis interactions. Specifically, it is important to know whether cis and trans binding have distinct functional effects and, if so, how a single cell discriminates between interactions in cis versus trans. Further, what are the structural features that allow certain cell surface receptors to engage ligand both on the same as well as on an apposed cell membrane? Here, we summarize known examples of receptors that display cis-trans binding and discuss the emerging diversity of biological roles played by these unconventional two-way interactions, along with their structural basis.

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Estudio de muestras recolectadas con el BIONESS a varias profundidades en trece estaciones.

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Occurrence of adults and biological aspects of Geniates borelli Camerano (Coleoptera, Scarabaeidae, Rutelinae) in Aquidauana, Mato Grosso do Sul, Brazil. Due to the importance of Geniates borelli Camerano as a pest in many crops, studies were developed at Universidade Estadual de Mato Grosso do Sul, Aquidauana campus, MS, Brazil. Adults were collected with a light trap from January 2006 to December 2007. 3,320 adults were collected, and the highest quantities were obtained in October 2006 and November 2007, with 1,548 and 802 adults recorded, respectively. Collected adults were kept in plastic containers with soil and Brachiaria decumbens seedlings for oviposition. 535 eggs measuring 2.30 × 1.60 mm were obtained. As the embryonic development progressed, eggs increased in size to 3.00 × 2.70 mm, and this change occurred between 6 and 10 days after oviposition. The embryonic period lasted 17.9 days. The first, second, and third instars lasted 37.6, 49.7, and 74 days, respectively. The prepupal stage lasted 65.9 days and the pupal stage lasted an average of 18.5 days. The biological cycle is completed in 315.8 days, which characterizes the species as univoltine. The average longevity of females was 35.4 days and 28.5 days for males.

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Diatraea flavipennella (Box) (Lepidoptera, Crambidae) is one of the most destructive pests in sugarcane plantations in the Northeast Region of Brazil. Developmental characteristics and parasitism potential of the egg parasitoids Telenomus alecto Crawford (Hymenoptera, Scelionidae) and Trichogramma galloi Zucchi (Hymenoptera, Trichogrammatidae) were compared with the aim of selecting a suitable species for biological control of D. flavipennella. Both T. alecto and T. galloi developed well and were readily adapted to D. flavipennella eggs as host. Although, T. galloi presented higher viability, with more adults emerging per host egg and higher sex ratio, the developmental period (egg-adult) was shorter in T. alecto and female longevity was extended. In addition, T. alecto exhibited significant higher levels of parasitism during the first three days after emergence than T. galloi. Thus, both parasitoids studied here offer considerable potential for the control of D. flavipennella in sugarcane.

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The potential for "replacement cells" to restore function in Parkinson's disease has been widely reported over the past 3 decades, rejuvenating the central nervous system rather than just relieving symptoms. Most such experiments have used fetal or embryonic sources that may induce immunological rejection and generate ethical concerns. Autologous sources, in which the cells to be implanted are derived from recipients' own cells after reprogramming to stem cells, direct genetic modifications, or epigenetic modifications in culture, could eliminate many of these problems. In a previous study on autologous brain cell transplantation, we demonstrated that adult monkey brain cells, obtained from cortical biopsies and kept in culture for 7 weeks, exhibited potential as a method of brain repair after low doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) caused dopaminergic cell death. The present study exposed monkeys to higher MPTP doses to produce significant parkinsonism and behavioral impairments. Cerebral cortical cells were biopsied from the animals, held in culture for 7 weeks to create an autologous neural cell "ecosystem" and reimplanted bilaterally into the striatum of the same six donor monkeys. These cells expressed neuroectodermal and progenitor markers such as nestin, doublecortin, GFAP, neurofilament, and vimentin. Five to six months after reimplantation, histological analysis with the dye PKH67 and unbiased stereology showed that reimplanted cells survived, migrated bilaterally throughout the striatum, and seemed to exert a neurorestorative effect. More tyrosine hydroxylase-immunoreactive neurons and significant behavioral improvement followed reimplantation of cultured autologous neural cells as a result of unknown trophic factors released by the grafts. J. Comp. Neurol. 522:2729-2740, 2014. © 2014 Wiley Periodicals, Inc.

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Biological aspects of Leucothyreus alvarengai Frey and Leucothyreus aff. semipruinosus Ohaus (Coleoptera, Melolonthidae, Rutelinae) in crop succession at central Brazil. Beetles of the family Melolonthidae make up a large group and some species are considered pests of planted crops. Little information is available on the basic biological aspects of the genus Leucothyreus, such as association with cultivated crops and their occurrence periods. Therefore studies were developed in soybean and corn crops in Tangará da Serra, Mato Grosso, Brazil, with the objective of studying the occurrence and biological aspects of Leucothyreus alvarengai Frey and Leucothyreus aff. semipruinosus Ohaus. For acquisition of immature specimens of both species, in April 2011 sampling was performed in corn fields, in July and October in the fallow area, and in soybeans fields planted in December; in 2012 sampling was performed in January and February in soybean fields and in March in corn fields. In 2011 the total number of larvae obtained in April, July, October and December were 100, 6, 30 and 27, and in January, February and March of 2012 these quantities were 32, 52 and 65 larvae, respectively. In all sampling events the larvae of L. alvarengai were collected in greater quantity. At the beginning of the reproductive period of L. alvarengai and L. aff. semipruinosus, it was observed that the adults began to fly and soon after started oviposition in the field in September. The appearance of larvae coincides with the time of soybean planting in the field, thus the larvae feed on roots of soybean plants at the beginning of their development and the cycle from egg to adult of the two species was completed in one year.

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Lagochile emarginata (Gyllenhal): morphology of immature and imago, and biological records (Coleoptera, Scarabaeidae, Rutelinae). The last larval instar and pupa of Lagochile emarginata are described. Pupa of the genus Lagochile Hoffmannsegg, 1817 is described for the first time. Redescription of the imago, clarifications on the morphology of immature Scarabaeoidea and biological notes are presented.

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Biological aspects of Leucothyreus ambrosius Blanchard (Coleoptera, Melolonthidae, Rutelinae). Coleopterans of the family Melolonthidae comprise a large group of species that feed on different food sources, including plant roots, stems, and leaves, in addition to plant materials at different decomposition stages. Several species are found in the genus Leucothyreus, occurring in different regions of Brazil, including the various biomes in the country. Information on the biology of species of the genus Leucothyreus is scarce, therefore, we conducted studies on the biological aspects of Leucothyreus ambrosius Blanchard, 1850. The period of adult occurrence was determined with a light trap installed between a cropped and pasture area in the municipality of Aquidauana, Mato Grosso do Sul State, Brazil. Adults collected in the field were used to form insect pairs and the studies were initiated in the entomology laboratory as the adults began ovipositing. Adults were observed flying in the field from October to December. Eggs were obtained as pairs were formed and a colony was established, the embryonic period lasting 14.6 days on average. The larval period in the 1st instar lasted 21.6 days, in the 2nd instar 19.6 days, and in the 3rd instar, 85.6 days. The head capsule width was 1.48 mm in the 1st instar, 2.44 mm in the 2nd, and 3.83 mm in 3rd larval instar. The pupal stage had an average duration of 35.5 days. The egg to adult period lasted 173.3 days. Morphometric information for the larval and adult stages is presented in this study.

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No impact of Bt soybean that express Cry1Ac protein on biological traits of Euschistus heros (Hemiptera, Pentatomidae) and its egg parasitoid Telenomus podisi (Hymenoptera, Platygastridae). Biological traits of the stink bug Euschistus heros and its main biological control agent Telenomus podisi were evaluated under controlled environmental conditions (25 ± 2ºC; 60 ± 10% RH; and 14/10 h photoperiod) by placing first instar nymphs into Petri dishes with pods originating from two soybean isolines (Bt-soybean MON 87701 × MON 89788, which expresses the Cry1Ac protein, and its near non-Bt isoline A5547) where they remained until the adult stage. Due to gregarious behavior exhibited by first instar nymphs, they were individualized only when at the second instar. Adults were separated by sex and weighed, and pronotum width of each individual was subsequently measured. They were placed into plastic boxes containing soybean grains of the same soybean isoline as food source. Egg viability and female fecundity were assessed in adult individuals. Adult females of T. podisi (up to 24h old) were placed with eggs of E. heros from mothers reared on both soybean isolines. Nymphal development time, insect weight, pronotum width, sex ratio, female fecundity, and egg viability (% emergence) of Euschistus heros did not differ between treatments. Eggto-adult development time, female longevity, sex ratio, and percentage of parasitized eggs were not impacted by the Bt-soybean (expressing Cry1Ac protein). Results indicate that the Bt-soybean, MON 87701 × MON 89788, has no direct significant impact on the two studied species.

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Nyssomyia whitmani (Antunes and Coutinho, 1939) has been considered as a complex of cryptic species, and some of the populations of this complex plays an important role in the transmission of Leishmania spp. in Brazil. The present study reports the biological aspects concerning the productivity out of eggs and the development time of the descendants of females obtained in Dourados municipality, Mato Grosso do Sul state. The females were captured with modified electric aspirators, fed in hamsters and further individualized in containers for breeding. At the insectary, temperature and relative humidity were maintained on average of 24.5 °C and 67.3%, respectively. From 944 females 3737 eggs were obtained, 748 (20.0%) evolved to the stage of larvae, and 93 (12.4%) of these reached adult stage. The life cycle lasted 80.6 days and the last larval instar was the longest. The use of a higher protein diet revealed a significant improvement in larval development.

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Le but de cette thèse est d'étudier l'impact d'une appartenance groupale jouissant d'un supérieur dans la hiérarchie sociale sur la volonté de participer à des actions collectives en faveur d'une appartenance groupale désavantagée. Selon la Théorie de l'Identité Sociale, les individus sont en effet membres de plusieurs groupes simultanément, qui constituent autant d'identités sociales potentielles. Comme l'ont montré les recherches en sociologie du genre s'inscrivant dans le courant intersectionnel, les diverses catégories sociales auxquelles une personne appartient peuvent se trouver dans des positions différentes dans la hiérarchie sociale, plaçant ainsi les individus à l'intersection de divers rapports de domination. Toutefois, ces rapports ne sont pas indépendants les uns des autres, mais interagissent et contribuent conjointement à construire une façon spécifique de vivre et de percevoir l'expérience de la domination. Globalement, notre thèse montre que lorsque deux endogroupes dotés de statuts différents sont simultanément saillants, les individus tendent à agir prioritairement en accord avec les intérêts de l'endogroupe dont le statut est le plus élevé, au détriment de l'endogroupe dont le statut est le plus bas : les individus tendent en effet à adhérer à des idéologies qui contribuent à légitimer le maintien des inégalités intergroupes, ce qui a pour conséquence de réduire leur volonté de participer à des actions collectives en faveur de leur endogroupe de statut inférieur. - This thesis focuses on the impact of a high status ingroup on willingness to participate in collective action in favour of a low status ingroup. According to Social Identity Theory, individuals are members of various groups, each of which is a potential social identity. Moreover, the feminist sociological theory of intersectionality suggests that these various ingroups can occupy different positions in social hierarchies, placing individuals at the intersection of various relations of domination. However, these relations do not act independently of one another, but interrelate, and shape a specific way to live and perceive the experiences of domination. On the whole, our thesis shows that when two ingroups with different statuses are salient, people tend to acts uppermost in compliance with the higher status group interest, to the detriment of the lower status group : Indeed, people tend to agree with ideologies that contribute to legitimate the perpetuation of intergroup inequalities. Consequently their willingness to participate in collective action in favor of their low-status group is reduced.