26 research outputs found
Associação micorrízica e teores de nutrientes nas folhas de cupuaçuzeiro (Theobroma grandiflorum) e guaranazeiro (Paullinia cupana) de um sistema agroflorestal em Manaus, Amazonas
NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics
Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset
Foliicolous anamorphs of Mycosphaerella from South America
One species of Mycosphaerella, and four anamorph species are newly described in the present study. Passalora crotoniphila comb. nov. is described from Croton in Paraguay. New species from Brazil include: Mycosphaerella bixae sp. nov. and its Passalora anamorph from Bixa, Pseudocercospora cordiana sp. nov. from Cordia, Pseudocercospora macrospora stat. nov. from Bertholletia, and Pseudocercospora xenoannonicola sp. nov. from Annona.Articl
Aspectos epidemiologicos da vassoura-de-bruxa do cupuaçuzeiro na microrregiao de Belem, PA.
Foi conduzido experimento no campo da Embrapa-Centro de Pesquisa Agropecuaria do Tropico Umido, em Belem, PA (1°28' S; 48°27' W), de junho/91 a maio/94, com plantas de cupuacuzeiro (Theobroma grandiflorum (Willd. ex Spreng.) K. Schum.) com sete anos de idade, objetivando acompanhar o desenvolvimento de vassouras-de-bruxa vegetativas causadas por Crinipellis perniciosa ((Stahel) Singer), desde a sua emissao ate a producao de basidiocarpos. Foram determinados coeficientes de correlacao entre as variaveis epidemiologicas (emissao de vassouras, periodo verde, periodo de secamento, periodo pre-frutificativo, producao de basidiocarpos) e as variáveis climaticas (umidade relativa do ar máxima, brilho solar, precipitacao pluvial). A emissao de vassouras vegetativas foi maior em julho e agosto. Estas permaneceram verdes por 34,9 a 65,2 dias e secaram entre 5,8 e 10 dias. Apos sua emissao, as vassouras demoraram de 79,5 a 347 dias para iniciar a producao de basidiocarpos, que ocorreu principalmente a partir de maio, com pico em junho. As variáveis climaticas, umidade relativa do ar maxima e brilho solar, correlacionaram-se significativamente apenas com a produção de basidiocarpos, com efeito negativo e positivo, respectivamente.200