4 research outputs found
NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics
Xenarthrans â anteaters, sloths, and armadillos â 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
Ăndice de seleção para escolha de populaçÔes segregantes de feijoeiro-comum Selection index for choosing segregating populations in common bean
Os objetivos deste trabalho foram determinar a viabilidade de uso de um Ăndice de seleção baseado em somatĂłrio de variĂĄveis padronizadas no melhoramento genĂ©tico do feijoeiro-comum e identificar as populaçÔes segregantes mais promissoras em produtividade de grĂŁos, porte da planta e resistĂȘncia ao acamamento, simultaneamente. Foram avaliadas populaçÔes segregantes obtidas por cruzamentos em esquema de dialelo parcial (6x6). Os genitores utilizados foram divididos em dois grupos. No grupo I, foram utilizados genitores com grĂŁos do tipo carioca, de porte semiereto a prostrado. No grupo II, foram utilizados genitores com porte ereto, porĂ©m com grĂŁos fora do padrĂŁo comercial carioca. As geraçÔes F2 e F3 das combinaçÔes hĂbridas foram avaliadas em experimentos com delineamento de blocos ao acaso, com trĂȘs repetiçÔes e semeadura em novembro de 2007 e fevereiro de 2008, respectivamente. Os dados relativos Ă produtividade de grĂŁos, Ă nota de porte e Ă nota de acamamento foram padronizados (Zij) por parcela. A partir do somatĂłrio de Zij, obteve-se o Ăndice de seleção para as trĂȘs caracterĂsticas conjuntamente. Constatou-se que o Ăndice de seleção possibilita selecionar populaçÔes segregantes superiores, considerando simultaneamente a produtividade de grĂŁos e as notas de porte e de acamamento. As populaçÔes segregantes CV III 8511 x BRS 7762 Supremo, CV III 8511 x RP 166 e CV III 8511 x RP 26 sĂŁo indicadas para programas de melhoramento a fim de obter linhagens produtivas com plantas eretas e menor acamamento.<br>The objectives of this work were to determine the viability of using a selection index based on the sum of standardized variables in common bean breeding programs, and to identify the most promising segregating populations for grain productivity, plant growth habit and resistance to lodging simultaneously. Segregant populations obtained by crosses in partial diallel scheme (6x6) were evaluated. Parental genotypes were divided in two groups. Group I comprised parents of the carioca grain type, with semierect to prostate growth habit. Group II comprised parental lines with erect architecture, but with grains not classified as the standard carioca type. The F2 and F3 generations of the obtained hybrid combinations were evaluated in randomized block design, with three replicates and sowing in November 2007 and February 2008, respectively. Data of grain yield, score for plant growth habit and score for lodging were standardized per plot (Zij). The selection index for the three characters together was obtained from the Zij sum. This selection index makes it possible to choose superior segregating populations considering grain yield, scores for plant growth habit, and for lodging simultaneously. Segregating populations CV III 8511 x BRS 7762 Supremo, CV III 8511 x RP 166 and CV III 8511 x RP 26 are identified as promising for breeding programs for grain productivity, plant architecture, and resistance to lodging, simultaneously