The influence of microhabitat on the population dynamics of four herbaceous species in a semiarid area of northeastern Brazil.

Variation in annual rainfall is considered the most important factor influencing population dynamics in dry environments. However, different factors may control population dynamics in different microhabitats. This study recognizes that microhabitat variation may attenuate the influence of climatic seasonality on the population dynamics of herbaceous species in dry forest (Caatinga) areas of Brazil. We evaluated the influence of three microhabitats (flat, rocky and riparian) on the population dynamics of four herbaceous species (Delilia biflora, Commelina obliqua, Phaseolus peduncularis and Euphorbia heterophylla) in a Caatinga (dry forest) fragment at the Experimental Station of the Agronomic Research Institute of Pernambuco in Brazil, over a period of three years. D. biflora, C. obliqua and P. peduncularis were found in all microhabitats, but they were present at low densities in the riparian microhabitat. There was no record of E. heterophylla in the riparian microhabitat. Population size, mortality rates and natality rates varied over time in each microhabitat. This study indicates that different establishment conditions influenced the population size and occurrence of the four species, and it confirms that microhabitat can attenuate the effect of drought stress on mortality during the dry season, but the strength of this attenuator role may vary with time and species.

The influence of microhabitat on the population dynamics of four herbaceous species in a semiarid area of northeastern Brazil / A influência dos microhabitats sobre a dinâmica de populações de quatro espécies herbáceas em uma área semiárida no nordeste do Brasil

Abstract Variation in annual rainfall is considered the most important factor influencing population dynamics in dry environments. However, different factors may control population dynamics in different microhabitats. This study recognizes that microhabitat variation may attenuate the influence of climatic seasonality on the population dynamics of herbaceous species in dry forest (Caatinga) areas of Brazil. We evaluated the influence of three microhabitats (flat, rocky and riparian) on the population dynamics of four herbaceous species (Delilia biflora, Commelina obliqua, Phaseolus peduncularis and Euphorbia heterophylla) in a Caatinga (dry forest) fragment at the Experimental Station of the Agronomic Research Institute of Pernambuco in Brazil, over a period of three years. D. biflora, C. obliqua and P. peduncularis were found in all microhabitats, but they were present at low densities in the riparian microhabitat. There was no record of E. heterophylla in the riparian microhabitat. Population size, mortality rates and natality rates varied over time in each microhabitat. This study indicates that different establishment conditions influenced the population size and occurrence of the four species, and it confirms that microhabitat can attenuate the effect of drought stress on mortality during the dry season, but the strength of this attenuator role may vary with time and species.

Resumo A variação anual na precipitação é considerada o fator mais importante que influencia a dinâmica populacional em ambientes secos. No entanto, diferentes fatores podem controlar a dinâmica populacional em diferentes microhabitats. A hipótese deste estudo é que as variações de microhabitats podem atenuar a influência da sazonalidade climática sobre a dinâmica populacional de espécies herbáceas em uma áreas floresta seca (Caatinga) no Brasil. Então, objetivou-se avaliar a influência de três microhabitats (plano, rochoso e ciliar) sobre a dinâmica das populações de quatro espécies herbáceas (Delilia biflora, Commelina obliqua, Phaseolus peduncularis e Euphorbia heterophylla) em um fragmento de Caatinga da Estação Experimental do Instituto de Pesquisas Agronômicas de Pernambuco, no Brasil, durante um período de três anos. D. biflora, C. obliqua e P. peduncularis foram encontrados em todos os microhabitats, mas elas estavam presentes em baixas densidades no microhabitat ciliar. Não houve registro de E. heterophylla no microhabitat ciliar. O tamanho das populações, as taxas de mortalidade e de natalidade variaram ao longo do tempo em cada microhabitat. Este estudo indica que diferentes as condições de estabelecimento influenciaram o tamanho das populações e a ocorrência das quatro espécies e confirma que microhabitat pode atenuar o efeito do estresse hídrico sobre a mortalidade durante a estação seca, mas a força desse papel atenuador pode variar com o tempo e a espécie considerada.

The influence of microhabitat on the population dynamics of four herbaceous species in a semiarid area of northeastern Brazil / A influência dos microhabitats sobre a dinâmica de populações de quatro espécies herbáceas em uma área semiárida no nordeste do Brasil

Abstract Variation in annual rainfall is considered the most important factor influencing population dynamics in dry environments. However, different factors may control population dynamics in different microhabitats. This study recognizes that microhabitat variation may attenuate the influence of climatic seasonality on the population dynamics of herbaceous species in dry forest (Caatinga) areas of Brazil. We evaluated the influence of three microhabitats (flat, rocky and riparian) on the population dynamics of four herbaceous species (Delilia biflora, Commelina obliqua, Phaseolus peduncularis and Euphorbia heterophylla) in a Caatinga (dry forest) fragment at the Experimental Station of the Agronomic Research Institute of Pernambuco in Brazil, over a period of three years. D. biflora, C. obliqua and P. peduncularis were found in all microhabitats, but they were present at low densities in the riparian microhabitat. There was no record of E. heterophylla in the riparian microhabitat. Population size, mortality rates and natality rates varied over time in each microhabitat. This study indicates that different establishment conditions influenced the population size and occurrence of the four species, and it confirms that microhabitat can attenuate the effect of drought stress on mortality during the dry season, but the strength of this attenuator role may vary with time and species.(AU)

Resumo A variação anual na precipitação é considerada o fator mais importante que influencia a dinâmica populacional em ambientes secos. No entanto, diferentes fatores podem controlar a dinâmica populacional em diferentes microhabitats. A hipótese deste estudo é que as variações de microhabitats podem atenuar a influência da sazonalidade climática sobre a dinâmica populacional de espécies herbáceas em uma áreas floresta seca (Caatinga) no Brasil. Então, objetivou-se avaliar a influência de três microhabitats (plano, rochoso e ciliar) sobre a dinâmica das populações de quatro espécies herbáceas (Delilia biflora, Commelina obliqua, Phaseolus peduncularis e Euphorbia heterophylla) em um fragmento de Caatinga da Estação Experimental do Instituto de Pesquisas Agronômicas de Pernambuco, no Brasil, durante um período de três anos. D. biflora, C. obliqua e P. peduncularis foram encontrados em todos os microhabitats, mas elas estavam presentes em baixas densidades no microhabitat ciliar. Não houve registro de E. heterophylla no microhabitat ciliar. O tamanho das populações, as taxas de mortalidade e de natalidade variaram ao longo do tempo em cada microhabitat. Este estudo indica que diferentes as condições de estabelecimento influenciaram o tamanho das populações e a ocorrência das quatro espécies e confirma que microhabitat pode atenuar o efeito do estresse hídrico sobre a mortalidade durante a estação seca, mas a força desse papel atenuador pode variar com o tempo e a espécie considerada.(AU)

The influence of microhabitat on the population dynamics of four herbaceous species in a semiarid area of northeastern Brazil

Abstract Variation in annual rainfall is considered the most important factor influencing population dynamics in dry environments. However, different factors may control population dynamics in different microhabitats. This study recognizes that microhabitat variation may attenuate the influence of climatic seasonality on the population dynamics of herbaceous species in dry forest (Caatinga) areas of Brazil. We evaluated the influence of three microhabitats (flat, rocky and riparian) on the population dynamics of four herbaceous species (Delilia biflora, Commelina obliqua, Phaseolus peduncularis and Euphorbia heterophylla) in a Caatinga (dry forest) fragment at the Experimental Station of the Agronomic Research Institute of Pernambuco in Brazil, over a period of three years. D. biflora, C. obliqua and P. peduncularis were found in all microhabitats, but they were present at low densities in the riparian microhabitat. There was no record of E. heterophylla in the riparian microhabitat. Population size, mortality rates and natality rates varied over time in each microhabitat. This study indicates that different establishment conditions influenced the population size and occurrence of the four species, and it confirms that microhabitat can attenuate the effect of drought stress on mortality during the dry season, but the strength of this attenuator role may vary with time and species.

Resumo A variação anual na precipitação é considerada o fator mais importante que influencia a dinâmica populacional em ambientes secos. No entanto, diferentes fatores podem controlar a dinâmica populacional em diferentes microhabitats. A hipótese deste estudo é que as variações de microhabitats podem atenuar a influência da sazonalidade climática sobre a dinâmica populacional de espécies herbáceas em uma áreas floresta seca (Caatinga) no Brasil. Então, objetivou-se avaliar a influência de três microhabitats (plano, rochoso e ciliar) sobre a dinâmica das populações de quatro espécies herbáceas (Delilia biflora, Commelina obliqua, Phaseolus peduncularis e Euphorbia heterophylla) em um fragmento de Caatinga da Estação Experimental do Instituto de Pesquisas Agronômicas de Pernambuco, no Brasil, durante um período de três anos. D. biflora, C. obliqua e P. peduncularis foram encontrados em todos os microhabitats, mas elas estavam presentes em baixas densidades no microhabitat ciliar. Não houve registro de E. heterophylla no microhabitat ciliar. O tamanho das populações, as taxas de mortalidade e de natalidade variaram ao longo do tempo em cada microhabitat. Este estudo indica que diferentes as condições de estabelecimento influenciaram o tamanho das populações e a ocorrência das quatro espécies e confirma que microhabitat pode atenuar o efeito do estresse hídrico sobre a mortalidade durante a estação seca, mas a força desse papel atenuador pode variar com o tempo e a espécie considerada.

Spatial variation in the structure and composition of the herbaceous community in a semiarid region of northeastern Brazil.

In the arid and semiarid environments of the world, microhabitats serve as models for the structure of vegetation communities. The goal of this study was to identify differences in the structures of the herbaceous communities growing on a crystalline substrate and those growing on a sedimentary substrate in a semiarid region of northeastern Brazil. One hundred 1 × 1 m plots were established in each area for quantitative sampling, with 69 species recorded in the crystalline area and 76 in the sedimentary area. The average plant density was higher in the sedimentary area, and average diameters and heights were greater in the crystalline area. The families and species with a high Importance Value Index (IVI) and a high Mixed Ecological Value Index (MEVI) differed between the areas. Of the species with high densities, only four were found in both areas. Shannon-Weiner diversity index values in the crystalline (2.96 nats/ind.(-1)) and sedimentary (2.89 nats/ind.(-1)) areas were similar. Evenness values on both substrates were also similar (0.72 and 0.71 in the crystalline and sedimentary areas, respectively). This study shows that variations in plant establishment conditions between crystalline and sedimentary areas in a semiarid region of northeastern Brazil should be considered as structure-modeling factors for the herbaceous community.

Natural regeneration of the herbaceous community in a semiarid region in Northeastern Brazil.

This study aimed to describe and compare the interannual changes in the diversity and population structure of herbaceous plants in an anthropogenic area that has been regenerating for 15 years and to identify the similarities and differences in the biological attributes of the community compared with the characteristics of a regenerating conserved area. In total, 105 plots measuring 1 m(2) were established. In each plot, the herbaceous plants were identified, and their height and stem diameter were measured for two consecutive years. The herbaceous flora of the anthropogenic area was represented by 86 species in 70 genera and 27 families, and there were no significant differences in the average richness between years. The conserved area was represented by 71 species in 63 genera and 35 families, and there was a significant difference in the total richness between areas and between years, except when comparing the richness between the conserved area and the anthropogenic area during the second year. Considering both the anthropogenic and conserved areas, 123 herbaceous species were listed, and the similarity between areas was 60 %. For the anthropogenic area, the floristic similarity between years was 95 %, and in the fragment of the conserved area, the similarity was 74 %. The diversity and density were significantly different between years and between areas. Given these results, this study suggests that 15 years of natural regeneration for the caatinga is not sufficient to reestablish its native flora with respect to its herbaceous component.

Spatial variation in the structure and composition of the herbaceous community in a semiarid region of northeastern Brazil / Variação espacial na estrutura da comunidade herbácea em uma região semiárida do Nordeste do Brasil

In the arid and semiarid environments of the world, microhabitats serve as models for the structure of vegetation communities. The goal of this study was to identify differences in the structures of the herbaceous communities growing on a crystalline substrate and those growing on a sedimentary substrate in a semiarid region of northeastern Brazil. One hundred 1 × 1 m plots were established in each area for quantitative sampling, with 69 species recorded in the crystalline area and 76 in the sedimentary area. The average plant density was higher in the sedimentary area, and average diameters and heights were greater in the crystalline area. The families and species with a high Importance Value Index (IVI) and a high Mixed Ecological Value Index (MEVI) differed between the areas. Of the species with high densities, only four were found in both areas. Shannon-Weiner diversity index values in the crystalline (2.96 nats/ind.-1) and sedimentary (2.89 nats/ind.-1) areas were similar. Evenness values on both substrates were also similar (0.72 and 0.71 in the crystalline and sedimentary areas, respectively). This study shows that variations in plant establishment conditions between crystalline and sedimentary areas in a semiarid region of northeastern Brazil should be considered as structure-modeling factors for the herbaceous community.(AU)

Nos ambientes áridos e semiáridos do mundo, os micro-habitats modelam a estrutura das comunidades vegetais. O objetivo deste estudo foi identificar diferenças nas estruturas das comunidades herbáceas instaladas sobre o solo do embasamento cristalino e a bacia sedimentar em uma região semiárida do Nordeste do Brasil. Foram estabelecidas 100 parcelas de 1 × 1 m em cada área para amostragem das comunidades. Foram registradas 69 espécies na área cristalina e 76 na área sedimentar. A densidade média das plantas foi maior na área sedimentar e os diâmetros e as alturas médias foram maiores na área cristalina. As famílias e as espécies com maior Índice de Valor de Importância (IVI) e Índice de Valor Ecológico Mixto (IVEM) diferiram entre as áreas. Das espécies com maior densidade, apenas quatro foram encontradas em ambas as áreas. Os valores dos índices de diversidade Shannon-Weiner das áreas do cristalino (2,96 nats/ind.-1) e sedimentar (2,89 nats/ind.-1) foram semelhantes. Os valores de equabilidade, em ambas as áreas, também foram semelhantes (0,72 e 0,71, nas áreas cristalina e sedimentar, respectivamente). Este estudo mostra que as variações nas condições de estabelecimento das plantas entre áreas cristalinas e sedimentares, em uma região semiárida do Nordeste do Brasil, devem ser consideradas como um fator modelador da estrutura das comunidades herbáceas.(AU)

Micronuclei as biomarkers for evaluating the risk of malignant transformation in the uterine cervix.

We evaluated micronucleus and apoptosis occurrence among women with normal smears and women with different kinds of cervical abnormalities, i.e., inflammatory processes and low- and high-grade squamous intraepithelial lesions (N = 12, N = 10 and N = 27, respectively). The sample included 59 women who were seen at a public medical service for cervical cancer prevention in Feira de Santana, Bahia, Brazil. The diagnosis was established by means of cytological, colposcopic, and histopathological examination. Cytogenetic analysis was performed on 2000 cells from each woman and included assessment of micronuclei and nuclear degenerative abnormalities indicative of apoptosis (karyorrhexis, pyknosis and condensed chromatin). Micronucleus frequency was significantly higher in the women with high-grade squamous intraepithelial lesions than in the women without cervical abnormalities or inflammatory processes (P< 0.001) or in the women with low-grade squamous intraepithelial lesions (P < 0.005). The frequency of apoptosis was similar in women without cervical abnormalities and women showing high-grade squamous intraepithelial lesions (P > 0.50), and significantly lower in women without cervical abnormalities and in women showing high-grade squamous intraepithelial lesions than in women showing inflammatory processes or low-grade squamous intraepithelial lesions (P < 0.0001). These results indicate that, in addition to Papanicolaou cervical cytological analysis, it would be useful to use micronucleus analysis to screen women who are at risk of developing cervical cancer. The assessment of nuclear degenerative abnormalities indicative of apoptosis increased the sensitivity of this test.

[Fruit flies (Diptera: Tephritidae) and their parasitoids (Hymenoptera: Braconidae) associated to host plants in the southern region of Bahia State]. / Moscas-das-frutas (Diptera: Tephritidae) e seus parasitoides (Hymenoptera: Braconidae) associados às plantas hospedeiras no sul da Bahia.

The association among Anastrepha species, braconid parasitoids and host fruits in southern Bahia is recorded. Doryctobracon areolatus (Szépligeti) was associated with A. serpentina (Wied.) in Pouteria caimito, A. bahiensis Lima in Helicostylis tomentosa, A. sororcula Zucchi in Eugenia uniflora, and A. obliqua (Macquart) in Spondias purpurea. Anatrepha obliqua was unique in fruits of Averrhoa carambola, but associated with D. areolatus, Asobara anastrephae (Muesebeck) and Utetes anastrephae (Viereck). In Achras sapota, A. serpentina was associated with A. anastrephae and D. areolatus, while in Psidium guajava, A. fraterculus (Wied.) and A. sororcula were associated with D. areolatus and U. anastrephae.

Acute and subacute toxicity of Schinus terebinthifolius bark extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Schinus terebinthifolius Raddi (Anacardiaceae) has long been used in traditional Brazilian medicine, especially to treat inflammatory and haemostatic diseases. AIM OF THE STUDY: The objective of this study was to evaluate the acute and subacute toxicity (45 days) of Schinus terebinthifolius via the oral route in Wistar rats of both sexes. MATERIALS AND METHODS: For the acute toxicity test, the dried extract of Schinus terebinthifolius bark was administered in doses from 0.625 to 5.0 g/kg (n=5/group/sex) and in the subacute toxicity test the following doses were used: 0.25, 0.625 and 1.5625 g/kg/day (n=13/group/sex), for 45 consecutive days. RESULTS: In the acute toxicity test, Schinus terebinthifolius did not produce any toxic signs or deaths. The subacute treatment with Schinus terebinthifolius did not alter either the body weight gain or the food and water consumption. The hematological and biochemical analysis did not show significant differences in any of the parameters examined in female or male groups, except in two male groups, in which the treatment with Schinus terebinthifolius (0.25 and 0.625 g/kg) induced an increase of mean corpuscular volume values (2.9 and 2.6%, respectively). These variations are within the physiological limits described for the specie and does not have clinical relevance. CONCLUSION: The acute and subacute administration of the dried extract of Schinus terebinthifolius bark did not produced toxic effects in Wistar rats.

Espécies de moscas-das-frutas (diptera: tephritidae) na região do baixo jaguaribe, estado do ceará

ABSTRACT The objective of this study was to assess the diversity of fruit-fly species (Diptera: Tephritidae) in the Baixo Jaguaribe region, state of Ceará, Brazil. The collections of the fruit flies were made from October/2002 to December/2003, with McPhail traps and 5% hydrolyzed corn protein (food bait). The traps were set up in host trees of the fruit flies: guava Psidium guajava, mango Mangiferaindica, red-coat plum Spondias purpurea, West Indian cherry Malpighiaemarginata, star fruit Avherroa carambola, papaya Caricapapaya and melon Cucumis melo. In the laboratory, the fruit flies captured were separated from other insects, counted and preserved in 70% alcohol, and then identified by species. The species collected were: Anastrepha zenildae Zucchi (74.59%), Anastrepha sororcula Zucchi (13.87%), Anastrepha obliqua (Macquart) (1.08%), Anastrepha daciformis Bezzi (0.09%), Anastrepha consobrina (Loew) (0.09%), Anastrepha pickeli Lima (0.09%) and Ceratitis capitata (Wied.) (10.19%).

RESUMO O objetivo deste estudo foi conhecer a diversidade de espécies de moscas-das-frutas (Diptera: Tephritidae) na região do Baixo Jaguaribe. As coletas das moscas-das-frutas foram realizadas de outubro/2002 a dezembro/2003, utilizando-se armadilhas McPhail e proteína hidrolisada de milho a 5% (atrativo alimentar). As armadilhas foram instaladas em frutíferas potencialmente hospedeiras de moscas-das-frutas: goiaba Psidium guajava, manga Mangifera indica, serigüela Spondias purpurea, acerola Malpighiaemarginata, carambola Avherroacarambola, mamão Carica papaya e melão Cucumis melo. No laboratório, as moscas-das-frutas foram separadas dos outros insetos capturados, contadas e acondicionadas em recipientes com álcool 70%, até a identificação específica. As espécies coletadas foram: Anastrepha zenildae Zucchi (74,59%), Anastrepha sororcula Zucchi (13,87%), Anastrepha obliqua (Macquart) (1,08%), Anastrepha daciformis Bezzi (0,09%),Anastrepha consobrina (Loew) (0,09%), Anastrepha pickeli Lima (0,09%) e Ceratitis capitata (Wied.) (10,19%).

Redescoberta de tetrastichus giffardianus (hymenoptera: eulophidae) após 60 anos da sua introdução no brasil / Rediscovering tetrastichus giffardianus (hymenoptera: eulophidae) 60 years after its introduction in brazil

RESUMO Tetrastichus giffardianus (Hymenoptera: Eulophidae) foi introduzido em 1937 no Estado de São Paulo, Brasil, para o controle biológico da mosca do mediterrâneo, Ceratitis capitata (Diptera: Tephritidae). Apesar de na época este parasitóide ter sido criado em grandes quantidades e liberado em várias fazendas, nunca mais foi relatado no país, levantando controvérsias sobre seu estabelecimento. Este trabalho relata a redescoberta desta espécie no Brasil, mas em locais distantes de onde fora originalmente liberado. Estas novas ocorrências estão na Região Nordeste, onde T. giffardianus parece ter se adaptado melhor do que no território paulista.

ABSTRACT Tetrastichus giffardianus (Hymenoptera: Eulophidae) was introduced in 1937 in São Paulo state, southeast Brazil, to control the medfly, Ceratitis capitata (Diptera: Tephritidae). In spite of its being mass reared and released in several farms at that time, there were no further reports about its occurrence in the country, giving rise to controversies about its establishment. This paper deals with the rediscovering of T. giffardianus, but in a region far from where it was released. The new findings are in northeast Brazil, where this species seems to be better adapted to the local conditions.

UTILIZAÇÃO DA ANÁLISE DISCRIMINANTE EM ESTUDOS TAXONÔMICOS DE MOSCAS-DAS-FRUTAS DO GÊNERO Anastrepha Schiner, 1868 (DIPTERA: TEPHRITIDAE)

A discriminant analysis was carried out for four species of the fraterculus group, Anastrepha fraterculus (Wiedemann, 1830), A. obliqua (Macquart, 1835), A. sororcula (Zucchi, 1979) and A. zenildae (Zucchi, 1979). These species can be distinguished only by minor morphological characters of the aculeus apex and sometimes there is great difficulty in determining specific limits. The study was based on eight measurements of the aculeus and it was possible to separate the species using the discriminant analysis. Therefore, this analysis is an additional tool for the identification of Anastrepha species as it was already observed for many other groups of insects.

As moscas-das-frutas Anastrepha fraterculus (Wiedemann, 1830), A. obliqua (Macquart, 1835), A. sororcula (Zucchi, 1979) e A. zenildae (Zucchi, 1979) foram submetidas a uma análise discriminante. Essas espécies do grupo fraterculus distinguem-se unicamente com base em detalhes do ápice do acúleo, que por serem muito semelhantes, dificultam a identificação específica. A análise discriminante permitiu a separação das quatro espécies de Anastrepha, com base em oito medidas do acúleo. Portanto, essa é mais uma técnica para auxiliar as identificações de espécies de Anastrepha, como já acontece em muitos outros grupos de insetos.

UTILIZAÇÃO DA ANÁLISE DISCRIMINANTE EM ESTUDOS TAXONÔMICOS DE MOSCAS-DAS-FRUTAS DO GÊNERO Anastrepha Schiner, 1868 (DIPTERA: TEPHRITIDAE)

A discriminant analysis was carried out for four species of the fraterculus group, Anastrepha fraterculus (Wiedemann, 1830), A. obliqua (Macquart, 1835), A. sororcula (Zucchi, 1979) and A. zenildae (Zucchi, 1979). These species can be distinguished only by minor morphological characters of the aculeus apex and sometimes there is great difficulty in determining specific limits. The study was based on eight measurements of the aculeus and it was possible to separate the species using the discriminant analysis. Therefore, this analysis is an additional tool for the identification of Anastrepha species as it was already observed for many other groups of insects.

As moscas-das-frutas Anastrepha fraterculus (Wiedemann, 1830), A. obliqua (Macquart, 1835), A. sororcula (Zucchi, 1979) e A. zenildae (Zucchi, 1979) foram submetidas a uma análise discriminante. Essas espécies do grupo fraterculus distinguem-se unicamente com base em detalhes do ápice do acúleo, que por serem muito semelhantes, dificultam a identificação específica. A análise discriminante permitiu a separação das quatro espécies de Anastrepha, com base em oito medidas do acúleo. Portanto, essa é mais uma técnica para auxiliar as identificações de espécies de Anastrepha, como já acontece em muitos outros grupos de insetos.